The Andean Paepalanthus pilosus complex (Eriocaulaceae): a revision with three new taxa

Abstract A herbarium-based revision is provided for Paepalanthus pilosus and allies, five commonly confused species of cushion plants native to Andean paramo. These are placed in the recircumscribed Paepalanthus subsect. Cryptanthella Suess. The group includes Paepalanthus pilosus, Paepalanthus dendroides, and Paepalanthus lodiculoides. An additional two species and one variety are newly described: Paepalanthus caryonauta, Paepalanthus huancabambensis, and Paepalanthus pilosus var. leoniae. The latter two are Peruvian endemics, while Paepalanthus caryonauta is known from four countries, and has long been confused with other species. An additional, possibly undescribed taxon is noted from the Serrania de Perijá, Colombia. Five new synonyms and three lectotypes are proposed, and the common misapplication of some names is noted. Within the Paepalanthus pilosus complex, species differences were found in timing of peduncle elongation, sex ratio, and leaf, perianth, diaspore and nectary morphology. Ecological differences are suggested by specimen data and a review of ecological literature. Descriptions, photographs and maps are provided for all species, as is a key to the groups of eriocaulaceous cushion plants from Andean South America.


Introduction
Th e Eriocaulaceae (Liliopsida: Poales) are a family of 10 genera and about 1200 species, about 800 of which are Neotropical (Th e Plant List 2013; Giulietti et al. 2012). Th ey usually occur on wet sunny sites with sandy or otherwise acidic soils, and are most diverse in the central highlands of Brazil and the Guiana Shield of Venezuela.
Th e Paepalanthus pilosus complex includes seven of the currently recognized Andean species: P. barkleyi Moldenke, P. dendroides (Kunth) Kunth, P. dennisii Moldenke, P. karstenii Ruhland, P. lodiculoides Moldenke, P. pilosus (Kunth) Kunth, and P. schultesii Moldenke. Members of this complex are characteristic elements of wet peaty sites in climatically humid páramo and subparamo from Costa Rica to Bolivia. All exhibit the cushion plant growth form, or "pulviniform" habit, found among diverse fl owering plant families of high-elevation páramo (Luteyn 1999). Th e similar aspect of the plants, their reduced foliage and capitula, and the variable form of the cushions in response to environment, can make species recognition diffi cult, and indeed, misidentifi cations and misconceptions have been common in the taxonomic, fl oristic and ecological literature.
Th ese species are also easy to confuse with other Andean cushion plant species, including Eriocaulon microcephalum Kunth and the three Andean taxa of Paepalanthus subsect. Dichocladus Ruhland (P. dichotomus var. glabrescens Moldenke, P. ferreyrae Moldenke, and P. muscosus Körn.), but can be distinguished by fl oral and seed morphology and other microcharacters, as detailed below. Some of the 16 species of Paepalanthus subg. Platycaulon Mart. endemic to the Andes also proliferate from the base and have been described as cushion plants ("polsterförmig"; Tissot-Squalli 1997), but these have larger leaves 5-18 cm long arranged in rosettes, and may be more precisely described as "cushion-rosettes" (cf. Aubert et al. 2014a).
Th is study was originally focused on resolving taxonomy of the Peruvian members of the P. pilosus complex, but later expanded to a herbarium study of all Andean material at hand. While I attempted to describe all material available to me, including that of Colombia and Venezuela, a detailed study of North Andean material was outside the scope of this work. Both P. dendroides and P. pilosus exhibit more complex variation over their range than is found in Peru and Ecuador, and the descriptions may not entirely refl ect populations of northern South America. Results from more intensive fi eld or molecular studies may add much to our understanding.

Materials and methods
Specimens were examined from the herbaria F, MICH, and MO (acronyms by Th iers 2015). Images of additional specimens were examined online via JSTOR (2000 onward), as well as the virtual herbaria maintained by COL (www.biovirtual.unal.edu. co/ICN), P (science.mnhn.fr/all/search), NY (sciweb.nybg.org/science2/Virtual-Herbarium.asp), and UDBC (herbario.udistrital.edu.co/herbario/). A few additional specimen images were provided by curatorial staff at US, MO and RB. Specimens examined from online images only are cited with barcode number in brackets. Material from USM was studied from handheld digital camera photos, cited with "photo" in brackets. Specimens are listed by country in a north-south sequence, with Venezuela following Colombia, and within country alphabetically by province in boldface, and then by collector and number. In a few cases where practical, geographic groupings within provinces are also used and these are also in boldface.
Specimen localities were interpreted according to the label description and in some cases, published collecting records, and mapped manually using the Google "My Maps" application. Coordinates of the manually placed markers were retrieved as KML data. Final distribution maps were generated using ArcGIS. Estimated coordinates used for mapping are included in the Suppl. material 2.
Th e key characters used to diff erentiate Paepalanthus subsect. Dichocladus from P. subsect. Cryptanthella in the key were based on examination of the following vouchers. Leaf anatomy of the P. pilosus complex was studied from median hand sections of dried herbarium specimens. Leaves were boiled, stored in 70% alcohol, then rinsed, hand-sectioned in water, and mounted in 50% glycerine. Anatomical vouchers are as follows. Paepalanthus caryonauta Hensold leoniae Hensold: León 1597 (MO). Paepalanthus lodiculoides was not sampled due to diffi culty sectioning the very small leaves.
Floral measurements were made by ocular micrometer in a stereomicroscope. Except for the Colombian, Venezuelan and Central American material of P. dendroides and P. pilosus, fl ower samples of all available specimens were measured. Photos of dry fl owers, seeds and some capitula were taken with a Dino-Lite AM-413T USB Digital Microscope (Figs 2,5,7,9,10,12), and if necessary multiple images aligned and stacked in Photoshop. Seeds were photographed after wetting and re-drying to show hygroscopic structures. Figures 4D and 9B were photographed under a stereomicroscope, and leaf cross-sections (Fig. 3) were photographed under compound microscope. Figures 3F and 9B were compiled with Zerene Stacker software.
Conservation status could be assessed with confi dence only for taxa of very broad and very narrow distribution. Confi dent evaluation according to the IUCN (2014) criteria was diffi cult due to the patchy nature of suitable habitat in the Andes, my lack of fi eldwork, and insuffi cient knowledge regarding rate of habitat loss and other threats. For the taxa not assessed, I off er only notes which may be relevant to the subject, such as a rough estimate of distributional range.

Habit
All species in the group are perennials with a compact, fl at to rounded (pulviniform) cushion habit, formed by short densely branched sympodial stems covered with congested subulate leaves about 1−2 cm long. Infl orescences are solitary and terminal on young shoots, but soon overtopped by erect lateral shoots, and then appear either axillary or borne between two dichotomous branchlets. Th e cushions may reach up to 1 m in diameter (P. caryonauta) and 10 cm high (P. pilosus), with a hemispherical shape ( Fig. 1), though they may be much smaller. Aubert et al. (2014b), applying Rauh's (1939) taxonomy of cushion plant forms, categorized the cushion-forming Eriocaulaceae as the "Rasenpolster" type, or "tufted compact cushion," and presented P. pilosus ("P. karstenii") as an illustration of this growth form. Th is type of cushion is typical of herbaceous graminoids, in which a central taproot is lacking, and adventitious rootlets issuing from the leaf bases anchor it to the soil. It is perhaps translated more accurately as "turf cushion" (cf. Parsons and Gibson 2009). As cushions grow, dead organic matter accumulates in the interior (Fig. 1A, foreground). Later the older growth at the center may rot away, so that the cushion becomes ring-shaped (A. Cleef, pers. comm.). Th is is illustrated in a photograph by Cleef of P. lodiculoides var. fl occosus Moldenke in the fi eld (see Moldenke 1976, p. 50).

Leaf morphology
Leaf morphology is similar among species, with subtle diff erences found in color, thickening, and pubescence. Paepalanthus huancabambensis is distinguished by a deep blue-green leaf color, while P. dendroides has leaves distinctly pale green in drying. In other species, leaf color is variable. Th e upper leaf surface is persistently pubescent in P. huancabambensis and in P. dendroides of Huánuco and Cuzco. In P. pilosus of Peru and Ecuador, appressed pubescence commonly occurs on the upper surface near the apex, while robust scattered cilia extending to the distal margin are typical of plants from the northern part of the range. Paepalanthus caryonauta has a rounded leaf apex (Fig. 2C), with the cuspidate tip strongly defl exed if present, while P. pilosus has leaves acute to sharply aristate (Fig. 2D, F, H, J), and the other species have leaves acute but not aristate ( Fig. 2A, E).

Leaf anatomy
Th e 13 specimens sampled represent all taxa of the P. pilosus complex except P. lodiculoides. Th eir anatomy may be characterized as follows: Epidermal layer one cell thick of large rounded cells, with those of the upper epidermis slightly larger than the lower epidermis; leaf margin rounded, with smaller usually thicker-walled cells. Stomata abaxial only. In P. dendroides, the epidermal cells larger and mostly thinner-walled than in the other samples, partly collapsed and deformed in section. In other sampled taxa, the outer epidermal wall thickened, and sometimes heavily cutinized on one or both surfaces. Hypodermis absent. Mesophyll of dense to moderately loose short-armed chlorenchyma, with an adaxial palisade layer sometimes discernible. Veins mostly 5-7.
Vein buttresses (bundle sheath extensions) commonly absent in median section , with exceptions. In P. huancabambensis the three central veins were buttressed adaxially, and also more weakly or by the midvein only to abaxial epidermis (Fig. 3F). In P. caryonauta, a weak abaxial midvein buttress was noted in only one specimen, otherwise buttresses absent. All other samples studied lacked vein buttresses in median section, though they likely occur towards leaf base.
Some unusual anatomical features are present which may relate to the daily freezethaw cycles of high elevation paramo. First, the mesophyll often detaches cleanly from the epidermis in an intact layer enclosing the vascular bundles. Th is was conspicuous in the thick leaves of P. caryonauta and observed to some extent in all sampled taxa except P. huancabambensis. It can be seen in dry broken leaves, as well as in hydrated sections. Separation of mesophyll from the epidermis is known from petioles and leaves of various frost-resistant species of other families in connection with extracellular ice formation (Levitt 1956). In these species, extracellular ice crystals can form below the epidermis, drawing water from the parenchyma and causing it to shrink. Th e cells themselves do not freeze and the tissue rehydrates when it thaws, avoiding permanent damage. McCully et al. (2004) speculate that anatomically determined "fault zones" which accommodate subepidermal ice crystals enhance frost resistance in some species.
Unusual deformation of the bundle sheaths is also observed in some species. In P. caryonauta, P. huancabambensis, and most P. pilosus, cells of the bundle sheath ("endodermis" sensu Coan et al. 2002) are regularly rounded or only slightly compressed (Fig.  3A,F). However, in the observed material of P. dendroides and P. pilosus var. leoniae they are irregular in shape, sometimes fl attened so completely the inner walls touch, and the cells lateral to the bundles extend outward in characteristic fi nger-like rays ( Fig. 3C-E). Th is peculiar feature was observed even in young leaves. Partial distortion of the bundle sheath was also observed in P. pilosus var. pilosus (Fig. 3B). Th e semi-aquatic species P. dendroides tends to have thinner cell walls, which may be expected to deform more easily. However, P. pilosus var. leoniae, which occurs at the highest elevation for that species in Peru, in spite of its thicker cell walls, also showed highly distorted bundle morphology, with cells of the bundle sheath and phloem barely discernible. While some distortion of cells is to be expected due to the drying process, the consistent diff erences observed between taxa growing at similar elevations suggest other factors are involved.

Timing of peduncle elongation
Paepalanthus pilosus var. pilosus is distinguished, especially in Peru and Ecuador, by the capitula usually subsessile and partly contained within the peduncle sheaths at fl owering time (Fig. 2J). However, the peduncles often elongate dramatically in fruit, up to 10 times or more their length at anthesis (Fig. 11D). Th is delayed timing may serve to protect fl owers at anthesis while enhancing fruit dispersal in the extreme páramo habitat. Although peduncle length is known to be variable in this species, the correlation of elongation with fruiting has not been previously noted. In the other species, dwarf peduncles occasionally occur, probably in response to habitat, and slight elongation may occur after fl owering, but not to the dramatic degree observed in P. pilosus.

Arrangement of staminate and pistillate flowers
Most species have protogynous capitula, with pistillate fl owers at the periphery, and staminate fl owers in the center. Th e capitula are about 4-24-fl owered and usually strongly determinate, with no central fl oral primordia found at the start of anthesis. In capitula with relatively more fl owers (P. huancabambensis, some P. pilosus) the ratio of pistillate to staminate fl owers tends to be greater (up to 3:1) whereas in smaller capitula it approaches equality. Th e related taxon, treated as "Paepalanthus sp. A" below, diff ers by the fl owers more numerous (40 or more) and the pistillate and staminate disposed in alternating whorls, with staminate fl owers sometimes found in the outer whorl ( Fig.  11G). An unusual situation is found in P. lodiculoides, in which a variable sex ratio may be observed among capitula on the same plant. Wholly staminate capitula are frequent in this species, while bisexual capitula show variable ratios of pistillate to staminate fl owers. Wholly pistillate capitula were not observed.

Nectaries
In Paepalanthus and other genera of the Paepalanthoideae, modifi ed style branches may function as nectaries (Stützel 1984, Oriani et al. 2009). Th ese clavate structures have traditionally been termed "stylar appendages," (e.g., Ruhland 1903), but Stützel (1984), noting their homology to a style branch itself, substituted the term "Drüsen" (glands), and later "gynoecial nectaries" (Stützel and Gansser 1996), while Rosa and Scatena (2007), suggested "nectariferous branches of the style." Similar secretory structures in the base of the staminate corollas are sometimes termed pistillodes. For simplicity I have used the term "nectary" for these structures, which are similar in both the pistillate and staminate fl owers of the species treated here.
In P. lodiculoides (Fig. 10D) and P. dendroides (Fig. 7G) nectaries are usually colorless, weak and membranous, curving slightly or collapsing after anthesis. However, in southern Peru, nectaries of P. dendroides may be light pink or brown. In the staminate fl owers of these two species, the nectaries are well included in the corolla, only reaching about halfway to the sinuses of the tube. All other species have rigid dark brownish nectaries, which reach the sinuses of the corolla tube in the staminate fl ower, and are often well exsert from the pistillate fl owers, especially in fruit. In P. pilosus (Fig. 12B, D, I) and P. huancabambensis (Fig.  9I) the papillae rimming the top of the nectary are stiff -walled and mostly colorless, only partially collapsing after anthesis and contrast strongly with the dark-pigmented body of the nectary. Stiff -walled apical papillae may also be developed, to a lesser degree, in Peruvian specimens of P. dendroides. In Paepalanthus caryonauta (Fig. 5G) the apical papillae are less clearly diff erentiated in texture and color, and the whole structure uniformly dark brown.

Diaspores
In P. dendroides, P. huancabambensis, and P. pilosus var. pilosus the basal half of the fruiting sepals thickens along the midvein at maturity and recurves hygroscopically upon drying, presumably pushing the detached corolla and fruit upward to the capitulum surface (Figs 2A,D;7E;12G,H). Th is is similar to the "elevator mechanism" of dispersal, described by Trovó and Stützel (2011) for P. tortilis (Bong.) Körn. However, in P. tortilis, the tips of the sepals recurve sharply, while in the taxa described here, only the sepal bases thicken and refl ex, and the apex remains angled upward. Th e pilose corolla remains tightly attached to the fruit and is dispersed with it, leaving the sepals behind. In P. dendroides and to some extent in P. huancabambensis, the petals are broadly spatulate and densely pilose (Fig. 7), perhaps further facilitating dispersal, while in P. pilosus the persistent petals are relatively narrow (Fig. 12E, G). However, in P. pilosus the hygroscopic pseudotrichomes (rod-like epidermal wall remains) of the seed coat are slightly stiff er and more prominent than in any of the other species, while those of P. dendroides tend to be weak and fl accid (cf. Figs 5,7,10,12). Melcher et al. (2004), in a broad survey of paramo taxa, assumed on the basis of morphology that P. pilosus ("P. karstenii") is primarily wind-dispersed and secondarily water-dispersed. Th ey found that diaspores of this species will fl oat for at least three days and suggested that the persistent pilose petals, and perhaps the pseudotrichomes of the seeds, may function to trap air bubbles. SEM photos of the diaspore and seed are provided by Melcher et al. (2004). Th e diaspores of P. caryonauta ( Fig. 2B-C, Fig. 5K-M), P. lodiculoides (Fig.  2E, Fig. 10E), and P. pilosus var. leoniae (Fig. 12L) are of a diff erent type. In these taxa, both sepals and petals are uniformly thickened in fruit, the broad-based sepals strongly cymbiform-clasping, and the fruit dispersed enveloped by the entire perianth. Th e fruiting sepals lack any hygroscopic change in shape, and the swollen diaspores detach readily from the capitulum. Sepal thickening is best developed in the Peruvian populations of P. caryonauta, the thickening extending into the pedicels of the pistillate fl owers, which persist as conspicuous "stumps" on the otherwise naked receptacle after fl ower fall. To compare to Melcher's results with P. pilosus, I tested fl otation of two diaspores of P. caryonauta (Barclay 5136, Dudley 11194), which also fl oated for three days, probably due to the buoyancy of the thickened perianth tissue. Relative to P. pilosus and P. dendroides, however, wind dispersal in this species may be inhibited due to the increased weight and glabrate surface of the diaspore.
Th e staminate fl owers of P. caryonauta also incidentally thicken with age ( Fig. 5J), the corolla developing a thick columnar anthophore, possibly as a pleiotropic eff ect of the pistillate fl ower thickening. In the Peruvian plants the staminate fl ower pedicels are obsolete. In other species, the anthophore is membranous or fl eshy but narrowed toward the base, and staminate fl owers are normally pedicellate.

Ecology and distribution
Paepalanthus pilosus and allies occur strictly in wet and very wet paramo and subparamo formations of the Andes, often associated with Sphagnum. Most taxa, except for P. dendroides, occur at about 3100-4000 m on wet but probably not inundated sites. Of these, P. pilosus and P. caryonauta are the most similar in habit, both forming dense mats or cushions 30 cm or more in diameter and reported as locally abundant. Paepalanthus pilosus is the more commonly collected species, noted for its colonization of disturbed sites, and often cited in ecological studies of paramo as "P. karstenii." Further detail is found in the species discussions.
Th e principal distributions of P. pilosus and P. lodiculoides, on one hand, and P. caryonauta on the other, form an allopatric mosaic with respect to each other (Figs 6,8). In Colombia, P. caryonauta is found primarily in the central Cordillera, barely entering northern Ecuador at Páramo Angel, while P. pilosus is abundant in the eastern Cordillera and the Cordillera de Merida, Venezuela. Paepalanthus pilosus reappears in southern Ecuador and northern Peru, from the natural barrier of the Girón-Paute valley (cf. Jørgensen et al. 1995), continuing south through the Amotape-Huancabamba zone (sensu Weigend 2002Weigend , 2004. Paepalanthus caryonauta, in turn, is found at several localities from Central Peru south to La Paz, Bolivia, on the wet eastern slope. Paepalanthus lodiculoides, though less widespread, has a disjunct distributional pattern in South America which parallels that of P. pilosus. Parallel disjunctions may be noted in other pulviniform Andean Eriocaulaceae. Th e Andean species of P. subsect. Dichocladus have a collective distribution similar to that of P. pilosus, occurring in the northern part of the eastern Cordillera of Colombia (P. muscosus), and in the Amotape-Huancabamba Zone (P. dichotomus var. glabrescens, P. ferreyrae). On the other hand, Eriocaulon microcephalum, which occurs in the Central Cordillera of Colombia and northern Ecuador, as well as in central Peru has an Andean distribution paralleling that of P. caryonauta, but also touching the edges of the Amotape-Huancabamba Zone. In Ecuador, it reaches to southern Azuay (specimen data from TROPICOS 2015), but mostly occurs to the west of the Azuay populations of P. pilosus, on the opposite side of a presumed Pleistocene glacial migration barrier (Jørgensen et al. 1995, Fig. 3;Lozano et al. 2009, Fig. 1). From central Peru it reaches north into San Martín, where it is sympatric with P. pilosus var. leoniae.
Paepalanthus dendroides has a wide patchy range that overlaps that of both P. caryonauta and P. pilosus (Fig. 8), but generally occurs at lower elevations than the other taxa, mostly at 2400-3200 m, but as low as 1900 m in Antioquia, Colombia (Luteyn 10737) and up to 3800 m in southern Peru. It is the only species sometimes described as an emergent aquatic. It is also the only species of the group to be collected from the mountains of the Guiana Shield (Pico de Neblina, Venezuela-Brazil border). Together with P. pilosus it extends to Panama and Costa Rica as well, perhaps refl ecting the adaptation of the lightweight comose diaspores of these species for long-distance dispersal.

Hybridization
A number of suspected hybrids were detected in areas of sympatry. Th ese include a sterile intermediate between P. dendroides and P. caryonauta in Pasco, Peru, discussed under P. dendroides. In addition, material morphologically intermediate between P. caryonauta and P. pilosus has been collected in Colombia in areas marginal to the distribution of both species. At the Paramo de Frontino in the western Cordillera, an apparently fertile intermediate plant was found sympatrically with normal P. pilosus, and a similar intermediate, with abortive fl owers, was collected at the south end of the eastern Cordillera. Typical P. caryonauta is not known from either locality. (See P. caryonauta discussion.) Finally, as discussed under P. pilosus, long-term introgression with P. dendroides, or perhaps another local taxon, is suspected as a factor contributing to the unusually broad, and perhaps bimodal pattern of variation observed in P. pilosus in disturbed paramos near Bogotá, Colombia, but more study is needed. Ruhland (1903) placed P. pilosus (including P. dendroides) and P. karstenii in Paepalanthus series Leptocephali Ruhland, an artifi cial group of reduced mostly annual species with erect stems and terminal fascicles of infl orescences. However, P. pilosus and allies are perennial cushion plants with infl orescences borne singly, and are clearly out of place here. Th is misinterpretation may have been due to the fragmentary material available to Ruhland, as well as to Kunth's mischaracterization of P. dendroides as having infl orescences in terminal umbellate clusters.

Taxonomic affinities and placement
A convenient alternative placement for these plants is available in the overlooked subsection Paepalanthus sect. Paepalanthus subsect. Cryptanthella Suess., described to accommodate P. kupperi Suess. (syn. of P. pilosus) from Costa Rica. Suessenguth (1942) compared the new subsection to Paepalanthus subsect. Dichocladus Ruhland, a group characterized by its subdichotomously branched cushion habit. He distinguished P. subsect. Cryptanthella by the subterranean branching, with only the erect unbranched rosettes borne above ground. Solitary axillary peduncles were said to arise from near the base of these aerial stems, in comparison to P. subsect. Dichocladus, in which infl orescences are borne in the axis between paired dichotomous branchlets (Ruhland 1903). In fact, a similar sympodial branching pattern is found in both groups, with the peduncles terminal on erect leafy shoots at the time of initiation, but overtopped by one or two lateral shoots early in development. Th e apparent difference in habit is attributable to the tendency in P. pilosus to form prostrate mats, in comparison to the erect cushions formed by the more rigid stems and leaves in P. subsect. Dichocladus. However, the latter group diff ers sharply from the P. pilosus complex in a number of other characters (see key below), so Paepalanthus subsect. Cryptanthella is provisionally recognized as a distinct taxon, with a new description and circumscription here provided.
Th e species of P. subsect. Cryptanthella formally treated here are all Andean cushion plants. However, P. pilosus is very similar to a robust long-pedunculate taxon from páramo in the Serrania de Perijá, Colombia, discussed below under Paepalanthus species A. Further affi nities of the group are not clear. It was not sampled in recent cladistic studies (Andrade et al. 2010;Trovó et al. 2013), which found a deep division of Paepalanthus (ca. 440 spp.) into two major clades not readily distinguished by morphology. Some affi nity can be seen with certain long-stemmed species of P. sect. Polyactis Ruhland, as to branch architecture, simple style branches and tuberculate fl oral trichomes. Th ese include P. stuebelianus Ruhland and P. bongardii Kunth, both with a more lax, scrambling habit. However Paepalanthus sect. Polyactis also emerged as deeply polyphyletic in the analyses, and the species most similar to P. subsect. Cryptanthella were not sampled.

Taxonomic treatment
Due to the frequent confusion and misidentifi cation of all the Andean cushion plant taxa of Eriocaulaceae, a key distinguishing major groups is provided. Peduncle sheaths always present, the tips papery-thin and scarious, often splitting deeply into two or three segments before anthesis, glabrous or minutely tufted at apex, never ciliate around mouth; pistillate fl owers with sepals elliptic to spatulate, the tips not recoiling in fruit, and petals prominently pilose on outer and often inner surface; seeds with a whitish covering of matted or distinct pseudotrichomes after wetting. Type. Paepalanthus kupperi Suess. Plants cespitose or pulviniform, forming densely branched clumps with erect terminal shoots ca. 1-4 cm; infl orescences solitary, terminal, but soon overtopped by one or two sympodial branches; peduncle sheaths scarious, swollen at apex, usually splitting into two or three triangular segments; involucral bracts pale greenish to gold or blackish-brown, pilose, not or barely surpassing fl owers. Trichomes of the involucral bract and sepal apices subacute to rounded at apex, tuberculate; apical trichome tuft of bracts and sepals relatively short, surpassing perianth tip by less than 0.2 mm. Pistillate fl owers peripheral, the outer subtended by the broad inner bracts of the involucre; staminate fl owers central or rarely (P. lodiculoides) the whole capitulum staminate; the inner fl owers subtended by linear receptacular bracts, these often with sub-cucullate tips and carinate-clasping bases; pistillate fl owers pedicellate; the petals usually long pilose abaxially with tuberculate trichomes disposed in submarginal bands in the upper 1/2 to 2/3 of petal, and also in two dense tufts just inside the upper margin either side of the apex and securing the stigma, the petal tips not involute after anthesis. Gynoecium with stigmas simple; stigmatic nectaries colorless to reddish or dark brown, usually with a distinctly broadened large-papillate upper rim, the papillae in the basal two-thirds or more usually indistinct and scattered. Staminate fl ower corolla with anthophore usually at least half the total corolla length, membranous or fl eshy, corolla tube with three subacute lobes, non-involute after anthesis; staminal fi laments prominently fl eshy below the corolla lobes and often (not always) adnate to corolla, fl at and membranous distally, the tips sometimes turning red-brown with age; anthers whitish, exsert above the lobes, not retracted after anthesis, and often deciduous. Seeds with longitudinal rows of hygroscopic pseudotrichomes. Description. Densely branched cushion plants, the cushions reported to reach one meter in diameter (Dudley 11194), and 15 cm high (Barclay 5176). Branchlets 1-5 cm, densely and uniformly leafy. Leaves linear-subulate, 10-20 mm long including the open basal sheath 3-4 mm long, 1.2-1.7 mm wide at midpoint, ca. 2.5 mm wide at ampliate base; apex narrowly obtuse to rounded, if sharp-cuspidate the tip defl exed downward and not evident in adaxial view; inconspicuously appressed-pilose (rarely ciliate) in juvenile state, glabrate at maturity except for the irregularly ciliate basal sheath; "dark green and glossy" when fresh (Dudley 11060), chartaceous to subcoriaceous, the adaxial surface smooth, the abaxial surface often with margins prominently thickened in older leaves and 1-3 veins more or less salient. Infl orescences solitary and terminal, with one to four produced in succession along a sympodially branched axis, the lower appearing axillary. Peduncles (7-) 9-25 (-35) mm long, ca. 3-costate, obscurely angled, pale, glabrous to obscurely appressed-puberulent, usually with a collar of longer silvery hairs at apex investing base of involucre. Peduncle sheaths (9-) 10-17 (-25) mm long, equaling or surpassing the leaf mat by up to 5 mm, the lamina (tip) of the sheath 3-4 mm long, infl ated, scarious, somewhat cucullate, almost closed at the apex in bud before emergence of capitulum, tufted-ciliolate at apex when young, often glabrate, frequently splitting into 3 triangular segments with emergence of capitulum. Capitula 3-4 mm in diameter. Involucres subequaling fl owers at anthesis; involucral bracts 2-3-seriate, the outer bracts triangular-ovate to broadly ovate, dull gold, tinged gray or occasionally blackish on shoulders; the inner bracts usually more strongly pigmented except for the paler midvein; bracts bearded apically especially along upper midvein, the upper margin short-ciliate with proximal cilia slightly longer, often early glabrate abaxially. Bract and fl oral trichomes obtuse to clavate, subhyaline, obscurely ornamented within and very obscurely tuberculate. Flowers about 8-14 per capitulum, the pistillate fl owers peripheral, the staminate central, equalling to subequalling the pistillate in number; the receptacle sparingly pilose or pilose only toward center. Receptacular bracts equaling to subequaling fl owers, broadly linear-subspatulate, ca. 6 times longer than wide, the apex often slightly cucullate and pubescent as the sepals, the base distinctly carinate, clasping. Pistillate fl owers: Pedicels ca. 0.1-0.35 mm, thick, glabrous, often becoming callose-thickened in fruit (Peru), leaving characteristic 'stumps' on the empty receptacle after abscission of fl owers. Sepals broadly obovate, strongly cymbiform, with apex convex-acute to obtuse (1.35-) 1.5-2.0 mm long × 0.6-1.0 mm wide (width variable within a fl ower), (0.25-) 0.35-0.4 (-0.5) mm wide at the base; black-mottled on shoulders, the midvein area paler brown; shortciliate along upper margin and bearded with longer appressed hairs on upper dorsum; membranaceous to chartaceous at anthesis, enlarging slightly and becoming uniformly thickened, and often rigid in fruit, husk-like and non-hygroscopic, enclosing the corolla and fruit and dispersed with it. Petals oblanceolate-spatulate, obtuse to often emarginate or truncate-emarginate, (1.2-) 1.35-1.7 (-1.85) mm long × (.35-) 0.4-0.7 (-0.8) mm wide, ca. 2.2-3.2 (-4.9) times longer than wide, cream to brownishtinged, with scale-like staminode at base, pilose abaxially near margins of distal half with more or less tuberculate trichomes, also densely tufted subapically within in two patches either side of the apex, which enfold the style branch; like the sepals becoming more or less rigid-thickened in fruit, the staminode also thickening and tightly adherent to both petal and ovary base. Gynoecium with ovary 0.5 mm at anthesis, ca. 0.85 mm in fruit; the style base 0.3-0.5 mm long; the nectaries with stalks 0.25-0.65 mm long, glandular portion 0.2-0.35 mm long, very dark brown or dark reddish, subclavate, with a ring of brown membranous papillae ca. 2-3 rows thick at the apex, the whole structure maintaining its shape after anthesis; style branches 0.6-1.0 (-1.2) mm long, usually ca. 0.2 mm longer than nectaries though often developing unequally, the stigmas simple, dark red-brown, non-involute after anthesis. Seeds subglobose to ellipsoid, mostly 0.6-065 mm long, 0.4-0.55 mm wide, red-brown, reticulate with short weak pseudotrichomes, sometimes glabrate. Staminate fl owers: Pedicels 0.15 mm to obsolete. Sepals (1.2-) 1.35-1.75 mm long × 0.5-0.85 mm, usually strongly and unequally fused at base for ¼-3/4 their length, obovate-navicular above, the apex obtuse-angled to broadly rounded, the tubular base often rigid and obconic at maturity; color and pubescence as in the pistillate fl owers. Corolla including anthophore 1.35-1.9 mm; the anthophore 0.65-1.35 mm long, usually ca. 60-70% the corolla length, ca. 0.2-0.35 mm diameter at base, fl eshy and columnar at maturity; the corolla tube 0.35-0.75 mm deep, fl eshy towards base especially opposite the fi laments, the corolla lobes hyaline to brownish, obtuse, 0.15-0.35 mm, not involute after anthesis; intermediate lobes lacking. Stamen fi laments with the basal half fl eshy, terete and adnate to the corolla, abruptly narrowed and loosely adhering to the lobes above, exsert 0.2-0.5 mm beyond the lobes, the exsert portion dark reddish-brown especially at tip; anthers cream-colored, ca. 0.3-0.35 mm long, usually deciduous after anthesis and not present in fruiting capitula. Nectaries similar to those of pistillate fl owers, reaching or slightly surpassing the corolla sinuses.

Paepalanthus caryonauta
Etymology. Th e epithet is taken from the Greek caryonaute (nom. sing.), the name given to the "nutshell sailors" in Lucian of Samosata's tale True Stories. It refers to the diaspores enclosed by the thick buoyant perianth.
Phenology. In Peru and Bolivia, collected in early anthesis in November and December, and with older infl orescences in all months from February to September. Th e dry season here is May to August but mitigated at higher elevations by cloud cover (Boyle 2001;Cano et al. 1995). In Colombia and Ecuador, collected on the wet eastern slopes in the slightly drier periods June to September and January; and on the drier western slopes, in the wetter months of March and December .
Distribution. Colombia (Central Cordillera): Cauca, Nariño. Ecuador: Carchi, probably Sucumbíos. Peru: Cuzco, Junín, Pasco. Bolivia: La Paz. In addition, some atypical specimens or hybrids (see below) are known from the Western and Eastern Cordilleras of Colombia, in Antioquia, Meta, and Norte de Santander. (Fig. 6) Habitat. In Peru and Bolivia, this species is restricted to a narrow band of wet paramo-like habitat on the high eastern slope of the Andes, while in Ecuador and Colombia it is found in open wet páramo. It is reported from boggy wet bunchgrass meadows (pajonal) with Calamagrostis Adans. or Festuca procera Kunth, in shallow waterlogged soil of ridgetops and rocky slopes, and in cloud forests and páramo degraded by fi re. In Ecuador and Colombia also reported from depressions in Espeletia páramo. Boyle (2001) describes the species as common in the Cordillera Vilcabamba (Peru: Cuzco/ Junín), forming a cushiony matrix together with mat-forming species of Xyris Gronov. and Apiaceae between tussocks of Calamagrostis. Elevation (2940-) 3100-4000 m.
Conservation notes. Th is species is known from two disjunct paramo zones, one about 475 km long in the northern Andes and one 950 km long in the central Andes. However, unlike related P. pilosus, it is not reported from disturbed areas, and rare outlying populations in Colombia show signs of introgression with P. pilosus. In the event of climatic drying or warming this species would be vulnerable, especially in the southern part of its range where suitable habitat is narrowly restricted to the eastern slope.
Paepalanthus caryonauta is readily distinguished from typical P. pilosus and P. dendroides by the obtuse leaf tips, and by the sepals uniformly thickened and persistent in fruit, to form an ovoid-ellipsoid diaspore. Even in anthesis, the sepals of P. caryonauta are about twice as broad at the base as those of P. pilosus and P. dendroides. Paepalanthus caryonauta can also be recognized by eye due to subtle diff erences in aspect and leaf orientation, with the leaves commonly fl atter and more ascending, i.e., less conduplicate and recurved than is commonly seen in P. pilosus. Boeke, who collected P. pilosus and an intermediate form of P. caryonauta at the same locality (see below), noted that in P. pilosus, the cushions were "easy to separate" and in P. aff . caryonauta, "diffi cult to separate." In the Cordillera Vilcabamba Dudley reported cushions up to 3 feet in diameter (Dudley 11194). However in disturbed roadside páramo at Acjanaco, Young and Cano (1994) comment on the paucity of cushion plants, and do not recognize P. caryonauta ("P. pilosus") as a signifi cant cushion plant species. For other diff erentiating characters, see Table 1.
Paepalanthus caryonauta has a more uniform morphology throughout its range than its close relatives. However, in Colombia and Ecuador the plants have less thickening in the leaves and fl owers, the presence of a short pedicel in the staminate fl owers, and peduncles often shorter at fl owering time, approaching those of P. pilosus in length.
Hybridization. Paepalanthus caryonauta and P. pilosus are mostly allopatric, but in Colombia there are points of contact where intermediates occur. Typical P. caryonauta is common in the Nudo de los Pastos and Central Cordillera of Colombia, from which only one historical collection of P. pilosus is known, collected ca. 1842. However at the isolated Paramo Frontino in the Western Cordillera, typical P. pilosus occurs sympatrically with a morphologically intermediate form of P. caryonauta. Th ese two elements were treated as "P. karstenii" and "P. karstenii var. corei," respectively, by Rangel-Ch. and Sánchez (2005) (Fig. 5P). Th e rounded glossy leaves resemble those of P. caryonauta, but those of Boeke & McElroy 269 have long scattered cilia at the upper margin, a trait otherwise only known in P. pilosus.
In the eastern Cordillera of Colombia, P. pilosus is abundant, while only two specimens suggesting atypical P. caryonauta were confi rmed, these from opposite ends of the eastern Cordillera, on east-facing slopes. At the south end, an intermediate plant, similar to that of Paramo Frontino, but with fl owers mostly abortive, was collected from the eastern slope of Sumapaz National Park (S. Diaz-Piedrahita 2608). Th is location is just south of the southernmost confi rmed Colombian collection of P. pilosus. To the north, Cuatrecasas 10302 (F), collected at the "extreme east" of Paramo Santurban (Norte de Santander) may represent P. caryonauta or a hybrid intermediate, diff ering by the light gold bracts. Sympatric taxa in this area include P. dendroides, typical P. pilosus, and the taxon treated below as Paepalanthus sp. A.
Phenology. In Central America, fl owering from March to April, in the dry season, and from August to September, the wet season, punctuated by a short dry period or veranillo (Grayum et al. 2004). In Antioquia, Colombia, collected mostly in rainy season from April to September. Elsewhere in Colombia, from July to February. In Peru, collected in anthesis from January to May (Cuzco, Pasco; wet season), and in August (Cajamarca, Huanuco; dry season); in post-anthesis from March to November.
Conservation status. Th e conservation status of this widespread species is presumed to be of Least Concern (IUCN 2014). However it may have recently disappeared from the disturbed paramos near Bogotá, where it hasn't been collected since 1917. Its lower elevation of occurrence and semi-aquatic habit may make it more vulnerable than its relatives to habitat loss due to disturbance.
Taxonomic history. Paepalanthus dendroides was initially described by Kunth and later Körnicke (1863) as having unbranched stems with leaves clustered toward the apex and peduncles "umbellate" or in terminal fascicles, a misinterpretation likely due to the small size of the specimens. In addition, Kunth described both P. pilosus and P. dendroides as having bifi d stigmas; his sketch of the gynoecium of P. dendroides is mounted on the lectotype sheet. Th e published plate shows only 3 bifi d stigmas, while the sketch shows three presumed fi liform "appendages," alternating with three thick shallowly bifi d "stigmas." Körnicke (1863) later corrected the description of P. pilosus to "stigmas simple" but accepted without comment the bifi d stigmas of P. dendroides. I have only seen a scan of the type, which clearly corresponds to P. dendroides as here treated, and can only assume Kunth either misinterpreted the gynoecial structure as he had done for P. pilosus, or examined an abnormal fl ower. Th ere are no species in this alliance or among any Andean Paepalanthus of similar habit, which have normally bifi d stigmas.
Paepalanthus dendroides was placed in synonymy of P. pilosus by Ruhland (1903), but the specialist Harold Moldenke (fl . 1930Moldenke (fl . 's-1980 generally distinguished the two species in his annotation work, misapplying the name P. pilosus to P. dendroides and to lax long-pedunculate specimens of P. pilosus, while using the name P. karstenii for most material of P. pilosus. (See detailed discussion under P. pilosus.) Th e name P. dendroides was removed from synonymy and its identity clarifi ed by Hensold and Hammel (2003), but is still commonly used for long-pedunculate plants of P. pilosus (cf. Madriñán and Zapata 2001).
Discussion. Paepalanthus dendroides is a variable species across its range, but may be distinguished from its close relatives by the character syndrome in Table 1. Th e broadly spatulate and densely pilose petals which enfold the diaspore, together with reduced pigmentation of the gynoecia, fi laments and seeds, are characteristic. Th e subaquatic habit and the lower elevation range are distinctive as well. It tends to have a less congested habit and softer leaves than its relatives, but also may form compact, stiff - leaved cushions with dwarf peduncles on some sites, as in the type of P. karstenii var. corei, and then fl oral characters may be important for identifi cation. It should be noted that key characters useful for Costa Rican material (Hensold and Hammel 2003) do not consistently apply in South America, including the pale-striped sepal midlines, the constricted peduncle apex, and the dorsally glabrous involucral bracts. Th ese characters are variable in Colombia and rare in Peru.
Of the Peruvian collections, those from Huánuco, Cuzco, and Puno share a similar morphology, with leaves relatively narrow and conspicuously pilose above, the outer involucral bracts dusky gray, and the nectaries somewhat pigmented. Leaf pubescence easily distinguishes these populations from sympatric P. caryonauta. In comparison, specimens from Cajamarca and Pasco have broader, glabrous leaves. Th e Cajamarca collections were examined only from photos, but the plants closely match Colombian material of P. dendroides and are from a similar habitat and elevation. Th e Pasco collection (Vasquez 29038) has fl oral characters somewhat intermediate with P. pilosus or P. caryonauta, as follows: petals 2.0-2.3(-3.0) times longer than wide; style base 0.4-0.5 mm; nectaries darker, 0.85-0.95 mm long; styles to 1.0 mm long; nectaries of male fl owers almost reaching the mouth of the corolla.
Evidence of hybridization. Th e Pasco, Peru, specimen (Vásquez 29038) was collected very near a plant fully intermediate between it and P. caryonauta, with abortive locules and stigmas (Monteagudo 7938; full specimen citation under P. caryonauta). Typical P. caryonauta (Monteagudo et al. 16143) is recorded 20 km to the east.
In Colombia, introgression between P. dendroides and P. pilosus is suspected in the disturbed paramos east of Bogotá. Although P. dendroides was originally described from near Bogotá, I have only seen one other typical individual from this vicinity (Pennell 1997), collected at Quebrada Chapinero in 1917, the same locality where the type of P. schultesii (=P. pilosus) was collected in 1941. Paepalanthus pilosus is presently abundant near Bogotá, but seems particularly variable and with an unusual tendency to long peduncles, lax habit, and variably shaped bracts, suggesting intermediacy with P. dendroides (see P. pilosus discussion). Typical P. dendroides is currently found north of Bogotá, where it is mostly recorded from elevations 500-900 m lower than nearby collections of P. pilosus. In Panamá, however, typical P. dendroides and P. pilosus are sympatric at the Cerro Fabrega massif, without apparent intermediates. Diagnosis. Plants forming loose cushions or mats; leaves blue-green, pilose above, older leaves strongly costate below; peduncle sheaths 25-30 mm, very lax, and strongly exsert from the leaf mat, the involucral bracts dark brown, the heads with over 20 fl owers; pistillate fl ower petals spatulate, pilose; nectaries dark red-brown and rigidulous, those of the male fl owers equaling the corolla sinuses. Description. Plants short-caulescent, with erect actively growing shoots to 4 cm, densely leafy, branching to form rounded mats. Leaves subulate, acute, 13-22 mm long × 1-2 mm wide at midpoint, tip cuspidate to apiculate, densely pilose to villous above with appressed to spreading white tuberculate hairs, upper margin eciliate, lamina dark blue-green, mature leaves prominently 3-5-costate below. Infl orescences solitary and terminal, soon overtopped by one or two erect lateral shoots which may fl ower in rapid succession, so that peduncles superfi cially appear fascicled. Peduncles 6.0-11.5 cm long at anthesis, perhaps continuing to elongate into fruiting, with peduncle of previous season up to 15 cm observed on same plant, ca. 3-costate, densely subappressed-villous especially above, with a dense sericeous collar of trichomes subtending involucre. Peduncle sheaths 25-30 mm, much surpassing the leaves, and strongly surpassing the leaf mat, scarious, very lax, nearly glabrous except for the tufted apex, the lamina cucullate, enclosing the bud when young and then splitting broadly into two or three triangular segments. Capitula 4-6 mm, depressed-hemispheric. Involucres subequaling fl owers at anthesis, and opening broadly at maturity; involucral bracts 2-3-seriate, the outer bracts triangular-ovate, greenish to uniformly dark brown, shaggy-ciliate on margins and villous in two submedial bands. Floral trichomes obtuse to clavate, strongly tuberculate. Flowers ca. 20-24 per capitulum, the pistillate fl owers peripheral, the staminate central, with 14-18 pistillate fl owers to 6 staminate fl owers (in two capitula sampled). Receptacle sparingly long-pilose with brownish hairs. Receptacular bracts subequaling fl owers, linear-subspatulate, the apex slightly cucullate, pubescent as sepals, the base sharply carinate. Pistillate fl owers: Pedicels 0.3-0.45 mm long, fi ne and membranous. Sepals broadly obovate-spatulate to subtruncate at apex, sometimes weakly cymbiform, 1.55-1.65 mm long × 0.65-0.8 mm wide at middle, 0.15-0.2 mm wide at base, blackish-brown, short-ciliate (apical cilia to 0.17 mm) along upper margin, and appressed-long-pilose in two bands fl anking the upper dorsum, the basal half of the midrib hygroscopically thickened, spadiceous-brown in fruit, and recurving when dry, the broad upper half of the sepal remaining chartaceous, erect; sepals detaching from fruit on dispersal. Petals spatulate, obtuse, brownish at tip, 1.25-1.35 mm long, the widest in a fl ower ca. 0.65 mm wide, ca. 2.2 times longer than wide, bearing scale-like staminodes at base, densely long-pilose with long tuberculate hairs on abaxial upper half except for midvein, also tufted subapically within, the hairs enfolding the style branch, petals not thickening in fruit, dispersed with fruit. Gynoecium with style base 0.35 mm long; nectaries ca. 0.7 mm long, dark red-brown, penicillate to subclavate-infundibular, with fringe of colorless stiff -walled papillae at mouth, these rigidulous and maintaining shape after anthesis; style branches 0.85 mm long, thick and dark red-brown, non-involute. Only two slightly misshapen seeds seen, 0.6-0.63 mm long, pinkish to red-brown, the pseudotrichomes weak. Staminate fl owers: Pedicels 0.35-0.4 mm, membranous, nearly glabrous. Sepals 1.6-1.7 mm × 0.5-0.6 mm, spatulate to obrhombic or subtruncate, color and pubescence as in the female fl owers, narrowed toward base and shallowly fused. Corolla 1.8 mm long; the anthophore 1.15 mm long, comprising ca. 65% the length of the corolla, grading from 0.15 mm wide at base to 0.35 mm wide at apex; the tube 0.65 mm long including well-defi ned brownish-tinged lobes. Filaments brownish-tinged above; exsert not more than 0.3 mm beyond lobe tips, anthers persistent, cream to light brownish. Nectaries equaling corolla sinuses.
Conservation status. Assessed as Critically Endangered, according to IUCN Criteria B1ab(iii) (IUCN 2014). Known from one locality in an unprotected area subject to deforestation, subsistence agriculture, and tourism.
Notes. Paepalanthus huancabambensis is similar in habit and dimensions to P. dendroides, but diff ers by its very lax, elongate peduncle sheaths well exsert from the leaf mat, and the large capitula with more fl owers. It also diff ers in the dark blue-green leaf color, compared to the consistently pale green leaves of the widespread P. dendroides, and preliminary anatomical study distinguishes it from that species by the presence of adaxial vein buttresses (bundle sheath extensions) in leaf median section. Th e broadly spatulate densely pilose female petals are similar to those of P. dendroides. However, the longer style base, the dark rigidulous nectaries with stiff colorless papillae fringing the rim, and the size of the nectaries relative to the corolla tube in the male fl owers all suggest P. pilosus.
Except for the lax peduncle sheaths, this species lacks any strong distinctive features of its own but its mixture of critical characters prevent it from being easily placed in any related species, and do not immediately suggest hybrid origin. It is endemic to the Cordillera de Huancabamba near the border of Peru and Ecuador in the western part of the Andean chain. Notably, in the same vicinity are also found an atypical form of P. pilosus (Cano 16840, discussed under P. pilosus var. pilosus), and at higher elevations the only known populations of P. lodiculoides from Peru and Ecuador.  . Leaves 1.7-5 (-6.5) mm long including broad basal sheath, the sheath often com- prising half or more of the leaf length, the lamina subulate, dark to pale green, ca. 0.25-0.35 mm wide in the middle when mature, apex sharply acute (Loja) to subacute or minutely rounded; leaves densely congested along the short stems, and often half buried in deep woolly pubescence of the stem and lower leaf cilia, the tips glabrous. Peduncles (2-) 5-11 mm long, usually exsert 1 mm or more from sheaths and leaf mat at anthesis, obscurely 3-costate and often scurfy-pilose in lower half, rigid, subterete, and glabrous at apex. Peduncle sheaths (1.7-) 3-5 mm long, with an oblique scarious, sharp-acuminate to irregular or bifi d apex, glabrous or obscurely tufted apically, margins eciliate (but cf. S. steyermarkii type, see below). Capitula (1.4-) 2.5-3 mm in diameter. Involucres about equaling fl owers; involucral bracts ovate to orbicularovate, dark black-brown throughout or paler brown along midvein, tufted at apex with clavate to linear, smooth to slightly tuberculate trichomes. Flowers ca. 4-6 per capitulum, sex ratio of capitula varying widely, from fl owers all male to mostly female to some mixture of the two, even on same plant, the few fl owers mostly peripheral, subtended by broad upper involucral bracts; receptacular bracts only rarely produced, these narrower and more oblong than involucral bracts, and carinate at base. Pistillate fl owers: Pedicels sclerifi ed, blackish, 0.1-0.15 mm, persisting on receptacle as bumps. Sepals broadly elliptic to suborbicular, strongly rounded-cymbiform in fruit, 1.2-1.7 mm long by ca. 0.65 mm wide at middle, 0.35-0.45 mm wide at base, deep blackish brown, sometimes with a pale medial streak, tufted with trichomes at apex. Petals oblong-obovate to broadly spatulate, acute-erose to acuminate, 1.1-1.6 mm × 0.4-0.7 mm, cream to nearly black, the distal half moderately pilose on both surfaces in two submedial or submarginal bands. Gynoecium at anthesis with ovary ca. 0.3 mm, style column 0.3 mm, nectaries ca. 0.35-0.6 mm, the glandular portion about equaling the stalk, clavate, the papillae soft and membranous, concentrated at apex but scattered along outside, colorless or tinged orange-brown at base, style branches 0.7-0.9 mm, brownish. Seeds 0.55-0.6 mm long, reticulate with short pseudotrichomes; locule wall thin, dehiscent or in some specimens observed adhering to the seeds, and the locules splitting apart without dehiscing (perhaps only in dry material). Staminate fl owers: Pedicels 0.15-0.25 mm, brown. Sepals broadly spatulate, blackish toward apex, tufted; corolla with narrow membranous anthophore and broad tube with acute to acuminate lobes; anthers cream, exsert; the nectaries only half-equaling the corolla sinuses.
Conservation notes. Known from two disjunct bands of paramo, one 420 km long in the north, and one about 100 km long in the south, under cool wet conditions. Discussion. Paepalanthus lodiculoides is easily distinguished from all other species in the group by the tiny moss-like leaves, delicate peduncles, and small capitula. Th e diaspores enclosed by persistent sepals and petals are similar to those of P. caryonauta. According to Madriñán and Zapata (2001) this species forms larger and more compact cushions than P. pilosus at Páramo Chingaza, Cundinamarca. Pedraza-Peñalosa et al. (2005) describe the cushions as less than 2 cm tall, or only about half as tall as those of sympatric P. pilosus ("P. karstenii"). Th e branch architecture is similar to the other species but the dense cushions are sometimes distinguished by the many soft, nearly upright stems tightly packed together, possibly on wetter sites. Other individuals have shorter, more rigid stems and shorter branchlets. Th ere are also pronounced diff erences in the amount of stem pubescence and leaf coloration. A densely white-woolly form with long hairs on the stems and lower leaf margins was described as P. lodiculoides var. fl occosus, but treated as a synonym by Luteyn (1999). Th at synonymy is provisionally accepted here, since other characteristics are the same, and the diff erence in pubescence seems likely due to environmental variation. A photograph of mature ring-shaped cushions of the fl occose form was published by Moldenke (1976, p. 50).
Th is species is also unique in the complex for the variable sex ratios of the capitula, which may be all staminate to mostly pistillate on the same plant. Capitula with exclusively pistillate fl owers were not observed. Pedraza-Peñalosa et al. (2005) describe capitula with staminate fl owers peripheral, but this was not observed in herbarium material.
Th e type of Syngonanthus steyermarkii Moldenke is the northernmost record of the species. It diff ers by the shorter peduncles (2-3 mm vs. 5-11 mm), shorter sheaths (1.7-2.2 mm vs. 3-5 mm) and capitula only about half the diameter of other specimens (1.4-1.5 mm vs 2.5-3 mm). Th e peduncle sheaths of this specimen are also abnormally developed, the apical lobe resembling an involucral bract in color and texture. Steyermark described the habitat as a limestone outcrop, which, if true, would be unusual for Eriocaulaceae, which almost universally occur on acidic substrates.
Th e three names cited in synonymy here were fi rst cited as synonyms by Luteyn (1999)

Paepalanthus pilosus (Kunth in H.B.K.) Kunth
Paepalanthus pilosus (Kunth in recurved, 7-16 (-20) mm long × (0.5-) 0.7-1.3 (-1.5) mm wide at midpoint; apex cuspidate-acute to short-aristate, the sharp tip evident in adaxial view; usually appressed pilose adaxially near tip (in Peru and Ecuador), the hairs smooth to roughened, in northern part of range usually with conspicuous long coarse scattered cilia to apex (rare in Peru and Ecuador), often early glabrate, bright green, texture chartaceous to rigidulous, the abaxial surface smooth or with nerves salient. Peduncles appressedpilose when young especially at apex, often only 1.5-8 mm long and surpassed by the sheaths at anthesis, but frequently and variably elongating up to ten or more times this length (20-100 mm) in fruit; in Peru and Ecuador only rarely up to 50 mm at anthesis and strongly exsert (Cano 16840); the sheaths 3-15 mm long, scarious and glabrous or minutely tufted at apex, splitting apically into 2 or 3 triangular segments.
Capitula 3-6 mm in diameter, often borne among the leaves at anthesis, frequently exsert in fruit, more rarely exsert at fl owering. Involucral bracts equaling the capitulum to slightly surpassing it, the outer bracts 1.6-4.2 mm long, ovate to often triangular, pale gold or greenish especially along midvein, pilose on upper back to merely tufted or glabrate, the inner bracts more broadly ovate to triangular, sometimes tinged grayish-brown on shoulders; receptacle long-pilose. Trichomes of bract and sepal apices subacute to bulbous, obscurely tuberculate. Flowers ca.10-16 per capitulum, the pistillate peripheral, usually 1-2 (-3) times as many as the staminate fl owers. Pistillate fl owers: Pedicels 0.35-0.5 mm, fi ne or rarely wide and spongy, not thickened-rigid in fruit. Sepals elliptic to obovate or oblanceolate, apex acute to rounded, the base linear-ligulate to narrowly cuneate, 1.4-2.65 mm long, 0.3-1.1 mm wide at middle, 0.15-0.3 (-0.4) mm wide at base; usually tinged dusky brown above, rarely uniformly pale cream (Sagastegui 12242), short-tufted at apex, ciliate at upper margins, and usually pilose either side of the dorsal midvein; the basal half of the midrib hygroscopically thickened, spadiceous-brown in fruit and recurving when dry, the margins and distal half of the sepal remaining chartaceous, erect; sepals detaching from diaspore before dispersal. Petals oblanceolate-spatulate, acute to obtuse to emarginate, rarely (Wurdack 1616) broadly cuneiform; apex truncate-emarginate, apiculate; 1.5-2.35 mm long × 0.3-0.75 (-1.0) mm wide, ca. 2-6 times longer than wide, cream to brownish-tinged, pubescence similar to P. caryonauta; usually not thickening in fruit, dispersed with the fruit. Gynoecium with style base 0.5-1.05 mm, nectaries with stalks 0.3-0.6 mm long, glandular portion dark red to brown, 0.3-0.4 mm long, penicillate with stiff whitish papillae at upper margin (northernmost Peru and northwards), or 0.4-0.5 mm long, clavate-infundibular with stiff whitish sometimes elongate papillae distributed along the outer surface, densest at the rim (Cajamarca: Celendín, Amazonas: Chachapoyas); papillae rigidulous after anthesis; styles 0.8-1.1 mm long (Barbour 3427: 1.4-1.6 mm long), dark red-brown. Seeds 0.55-0.8 mm long, red-brown, reticulate with abundant white erect to suberect pseudotrichomes. Staminate fl owers: Pedicels 0.2-0.5 mm. Sepals 1.2-2.45 mm, fused at base unequally, from very briefl y to about 1/3 sepal length, obovate to usually spatulate, acute to rounded, narrowed to base and not thickening with age. Corolla 1.2-2.5 mm long, the anthophore 0.5-1.5 mm long, comprising 30-65 % the corolla length, membranous and 0.1-0.2 mm diameter at base, broadening to 0.2-0.3 mm near apex; the corolla tube including lobes 0.5-1.65 mm long. Filaments similar to P. caryonauta, usually dark red-brown between apex and the base of the corolla lobe, exsert ca.0.2-0.5 mm beyond the lobes. Nectaries reaching the sinuses of the corolla tube. Phenology. In Central America, mostly collected January to May, and in July, coinciding with the main dry season, and possibly a shorter second dry season (veranillo), respectively (Grayum et al. 2004). In the climatically wet paramos of Colombia and Venezuela, peak fl owering is June to December, generally the wet season Cuello et al. 2010;Vareschi 1970), though probably coinciding with short dry periods, as observed by Pedraza-Peñalosa et al. (2005). In Peru, fl owering and fruiting mostly from July to September, during a pronounced dry season; in Ecuador, also during predominantly dry months from September to November (to January), fruiting through April.
Distribution. Costa Rica (Cerro Talamanca) Peru (to 7° S lat.): Amazonas, Cajamarca, Lambayeque, Piura. (Fig. 6) Habitat and ecology. Common and characteristic ground cover (rasante) or cushion species of wet páramo, rarely subpáramo, on boggy organic soils, or at pond and bog margins but not in standing water (Schmidt-Mumm and Vargas-Rios 2012); often associated with Sphagnum, usually growing amongst shrubs or bunchgrass, in Colombia frequently also with bamboo (Chusquea tessellata Munro) or Espeletia spp. Rangel-Ch. and Ariza 2000;Vargas and Rivera 1991). It is reported by some observers as growing at the base of bunchgrass (Franco-Rosselli et al. 1986) or shrubs (Weberbauer 1945) or under rock ledges, but is also reported in full sun. In Ecuador and the western cordillera of Peru, it is occasionally reported from montane forest. Elevation (2700-) 3000-4000 (-4400) m.
Paepalanthus pilosus is a commonly cited species in phytosociological analyses of North Andean paramo, usually under the name P. karstenii . It is reported as a "characteristic and dominant species" of the alliance Paepalantho karsteni -Chusquioni tessellatae in wet páramo east of Bogotá (Rangel-Ch. and Ariza 2000). It is tolerant of disturbance and may even have a minor role in succession, being reported by several collectors as locally abundant on wet banks and roadsides, and in regenerating burnt paramo. Cleef (1981) noted that it is one of the fi rst species after Castilleja to colonize burnt bunchgrass páramo. Cuello and Cleef (2009), in Venezuela, found it occurring abundantly in Sphagnum mats around the margins of an old lakebed undergoing succession to bunchgrass páramo, and suggested that this new azonal alliance (Sphagno-recurvi -Paepalanthion-pilosi Cuello & Cleef) was associated with disturbance by wildlife fragmenting the Sphagnum mat. Vargas and Rivera (1991, quoted by Rangel-Ch. et al. 1997) found P. pilosus in paramo disturbed by grazing cavies and rabbits. One collector reported that the plant forms an abundant 'necromasa' with good water-retaining properties relevant to peat formation (Bernal 1647).
Conservation status. Th e status of this widespread variable taxon, reported as a colonizer tolerant of disturbance, is presumed to be of Least Concern (IUCN 2014).
Taxonomic history. No type material is found for E. pilosum Kunth in the herbarium P-Bonpl. in Paris (Stauff er et al. 2012). Th e lectotype specimen chosen from Kunth's herbarium (B) includes two individuals of P. pilosus, with one short-pedunculate individual of P. dendroides mounted between them. Th e middle plant is a good match for the type of E. dendroides Kunth, described from the same locality. Kunth's concepts of the two species were based partly on the shorter peduncles in P. pilosus, but this character varies in both species. Kunth also diff erentiated E. pilosum by leaves rigid, "pilose-ciliate," with a sharp apex, and involucral bracts ovate, acute, while E. dendroides was described as having leaves acuminate, membranous and glabrous, and involucral bracts obovate. Th ese characters are adequate to distinguish the two elements on the sheet and to justify exclusion of the middle plant from the type material.
Paepalanthus pilosus has suff ered confusing taxonomic treatment over time. Körnicke (1863) recognized P. pilosus and P. dendroides (both described from Bogotá) as well as P. selaginoides (Popayán) as distinct taxa, distinguishing P. selaginoides by the near obsolete peduncles, and P. pilosus from P. dendroides by the robust scattered cilia of the leaf margin. Ruhland (1903) synonymized all three under P. pilosus with the claim that these diagnostic characters were too variable, sometimes even within specimens, an impression perhaps fostered by the mixed sheet of P. dendroides and P. pilosus from Kunth's herbarium. At the same time, Ruhland erected an additional new species, P. karstenii, also from near Bogotá, distinguished from P. pilosus by the "leaf indument and apex," the involucral bracts broad and glabrous abaxially, and "a diff erent form of the perianth." Inexplicably, he also described capitula as 2-3 mm wide in P. pilosus versus 6-8 mm wide in P. karstenii, which accords neither with the type of P. pilosus (capitula 6.5 mm) nor earlier descriptions. How Ruhland thought the leaf indument, apex, or perianth in P. karstenii diff ered from that of P. pilosus is not clear from his description, leaving only the key character of bract pubescence, which also varies widely within species. In fact the broad (obovate) subglabrous bracts seen in the type of P. karstenii are more typical of P. dendroides as recognized by both Kunth and Körnicke. Th e identity of P. karstenii needs further study (see Doubtful Taxa). Moldenke (1975b) ostensibly followed Ruhland, treating P. dendroides as a synonym of P. pilosus, and distinguishing P. karstenii by the "involucral bracts glabrous on the outer surface," but his use of the names in annotations (ca.1930's-1980's) doesn't correlate with bract pubescence or shape. In his pattern of annotations, Moldenke revived the appropriate distinction between P. dendroides and P. pilosus, but confused the nomenclature, mostly annotating typical P. pilosus as P. karstenii, while applying the name P. pilosus to P. dendroides and occasional long-pedunculate individuals of P. pilosus. Th is convention was followed by later authors (e.g., Cleef 1981, Madriñán andZapata 2001). Huft's treatment (1994) was similar but treated Central American P. pi-losus as P. kupperi rather than P. karstenii. Hensold and Hammel (2003), in a treatment of Costa Rican species, re-established P. dendroides as a distinct taxon and corrected application of the name P. pilosus to accord with the original concept of Kunth and Körnicke, which includes both P. kupperi and most material determined as P. karstenii.
Moldenke did not specify distinguishing characters for his other species here placed in synonymy of P. pilosus, nor were these names widely used. Of his new infraspecifi c taxa, Paepalanthus karstenii f. corei was said to diff er from that species by the peduncles only 1-2 cm in length, and P. karstenii var. minimus by both leaves and peduncles shorter. Th e type of the former is in fact P. dendroides, though Moldenke most commonly applied the name to P. pilosus and P. caryonauta.
Paepalanthus espinosianus and P. loxensis were fi rst treated in synonymy of P. pilosus by León-Yánez and Hensold (1999), and P. subsessilis by Hensold (2008). Paepalanthus selaginoides was originally placed in synonymy of P. pilosus by Ruhland (1903) and is clearly closest to that species, but represents the only record of the species from the Central Cordillera of Colombia. Pending closer examination of the type, its placement here is provisional.
Discussion. Paepalanthus pilosus in Peru and southern Ecuador is characterized by the usually dwarf fl owering peduncles with capitula subsessile at anthesis, and the outer involucral bracts greenish or with a green midvein and often longer than wide. In this area, soft hirsutulous pubescence of the upper leaf surface near the apex, similar to that found in P. dendroides, is common. From Costa Rica to Colombia and Venezuela, long robust scattered cilia along the distal margin are frequent and diagnostic when they occur (hence the species epithet; cf. Fig. 2D), but rare in our area. Th ese cilia can often be detected even in older glabrate leaves due to the persistent enlarged basal cells. From P. dendroides, P. pilosus may also be distinguished by the relatively narrow elliptic to oblanceolate petals, and the prominent dark rigid nectaries; and from P. caryonauta by the usually larger capitula, the sharply acute to aristate leaf tips, and (in the typical variety) by the form of the fruiting calyx. (See Table 1.) Habit varies from a dense compact mat pressed horizontally by collectors (as in the type of P. espinosianus Moldenke), to a rounded cushion with branch lengths of a few centimeters, pressed and mounted vertically (as in the type of P. loxensis Moldenke) Th e superfi cial diff erence in aspect of these two forms caused Moldenke to ally the former species with P. karstenii, but the latter species with P. glaziovii Ruhland (subsect. Dichocladus). Th is character almost certainly varies in response to habitat, as Heilborn (1925) noted in the vegetatively similar species Plantago rigida Kunth, which forms rounded cushions on wet sites and fl at mats on drier sites. Leaves may be ascending to strongly refl exed and appressed to the ground, the latter perhaps a response to drier or sunnier conditions. An example are the collections Hernandez-Schmidt 1330 and 1432 from the same locality in Cundinamarca, the former reported on rocks in full sun, with leaves refl exed close to ground, the latter on saturated soil, with leaves erect.
Peduncle length is highly variable, as already noted by Ruhland (1903), but much of this variation may be developmental. Actively fl owering capitula are usually borne on peduncles only a few millimeters long, barely emergent from the sheath, and in-vested by the sharp cuspidate tips of subtending foliage leaves. Dramatic peduncle elongation often occurs later in fruit, as shown by specimens bearing both subsessile fl owering capitula at stem tips, and fruiting capitula lower on the stem on peduncles up to ten times as long (e.g., Larsen 237, Fig. 11D). Th e delayed timing of peduncle elongation may aff ord wind and frost protection during anthesis, while later enhancing fruit dispersal. Peduncle elongation doesn't always accompany fruiting or may be minimal, but even in specimens with many subsessile fruiting capitula still embedded in the leaf mat, occasional remains of much longer peduncles can be found (e.g. Barbour 3427, Sagastegui 12242). Notably, the only specimen from Peru and Ecuador with peduncles already elongate (2-5 cm) at anthesis was also the only specimen reportedly collected from "montane forest," where it was said to be rare (Cano 16840). Th is plant may represent a taxonomically distinct variant, but for now is treated as an environmental form. In Colombian populations of the Eastern Cordillera, early peduncle elongation may be more common.
Other characters showing wide variation in Peru and Ecuador are involucral bract length, capitulum size, and fl ower and seed size. For example, the type of P. loxensis (Loja) contrasts sharply with that of P. espinosianus (Azuay) by its much smaller involucral bracts, capitula, fl owers, and seeds. Indeed, in most plants from Azuay, in the Cerro Fierro-Urcu (Loja), and in some localities in Peru (Jaén, Bagua, Celendín), outer involucral bracts are ca.2.6-4.0 mm, with the tips often surpassing the large capitula 4-6 mm in diameter (cf. Fig. 2H). In contrast, most specimens from southern Loja, the western Cordillera of Peru, and southern Amazonas, Peru, have involucral bracts about 1.6-2.6 mm long and capitula 3-4 mm in diameter ( Fig. 2I-J). Th e length of the pistillate fl ower sepals was measured in 18 specimens of Peru and Ecuador and was imperfectly correlated with capitulum size. Small fl owers (sepals 1.4-1.8 mm) were found in the small-capitate plants from southern Loja and northwestern Peru, and a few large-capitate plants of Azuay; all other specimens were large-fl owered (sepals ca. 1.8-2.4 mm long). Seed size showed the strongest geographic correlation, with the smallest seeds observed in the small-fl owered specimens from southern Loja and the western cordillera of Peru (0.53-0.63 mm, 5 samples), while elsewhere seeds were larger (0.67-0.8 mm, 8 samples). Among the large-fl owered collections, those of Amazonas, Peru, south of the mouth of the Rio Utcubamba (ca. 6° S latitude) are distinguished by the unusually broad female petals (l/w ratio 1.8-2.9 vs. 3.5-7.0 elsewhere), broadly rounded to even truncate-emarginate at apex (Fig. 12I), and by an ambiguous pattern of sepal thickening, both characters suggesting intermediacy with P. pilosus var. leoniae, of San Martín. Also shared with that variety are the funnelform nectaries ( Fig. 12I) with unusually large, spreading papillae (also found in Sagastegui 12242, Celendín), in comparison to the commonly penicillate nectaries with small papillae found elsewhere.
Paepalanthus pilosus in Colombia requires further careful study. In the Eastern Cordillera, particularly in disturbed paramo near Bogotá, there are more pronounced morphological extremes in the species than in other parts of its distribution. Here, leaf lengths range up to 3 cm, capitula from 3.5-8 mm in diameter, peduncles are occa- sionally strongly exsert at fl owering, and involucral bract color and form are variable, ranging from nearly obovate-rounded to narrowly triangular, and pale gold to dark pigmented on the shoulders. Madriñán and Zapata (2001) indicate two sympatric elements for the Páramo Chingaza, one with ciliate leaves and peduncles exceeding the leaves in length ("P. dendroides"), and one with leaves nearly glabrous and peduncles shorter ("P. karstenii"). However type material of both P. pilosus and P. karstenii have prominent scattered cilia of the leaf margins, and both have variable peduncle lengths, which may be quite long in fruit. Judging from the photographs, both elements from Páramo Chingaza fi t within my working concept of P. pilosus, but the presence of two reproductively isolated crypto-taxa in this area cannot be ruled out. Some diff erences especially in leaf size, orientation and pubescence may be due to microhabitat, but polymorphism does seem more exaggerated in collections from the vicinity of Bogotá than from elsewhere, and collectors have often recognized two elements at one locality (e.g., Barclay 4031,4057,Paramo de Guasca;Dwyer 8186,8189,Paramo Cruz Verde;Rangel 4045,4048,Boyacá,Duitama). For simplicity I have treated as P. pilosus all forms with subulate, sharply cuspidate leaves and the fl ower and fruit structure described above, and consider robust spreading cilia of the distal leaf margin also diagnostic when present, as it is in P. pilosus of Venezuela and Central America. Th is may however obscure a more complicated taxonomic picture.
Hybridization may be a factor contributing to the chaotic variation in P. pilosus in the vicinity of Bogotá. Some material, such as the type of P. karstenii (see Doubtful Taxa) looks intermediate with P. dendroides, as to elongate peduncles and rounded involucral bracts. Typical P. dendroides was originally described from Bogotá, but has not been collected in the vicinity since 1917, while it is still widespread elsewhere. In addition, probable hybrids between P. pilosus and P. caryonauta have been collected at the margins of the range of P. pilosus, at Paramo Frontino (Antioquia), and on the eastern slope of Paramo Sumapaz, south of Bogotá (see P. caryonauta discussion).
A fi nal complication in the taxonomy of Colombian P. pilosus is the presence in the Serranía del Perijá and vicinity of a closely related but more robust taxon, which may intergrade with it, discussed below under Paepalanthus sp. A.
Etymology. Named in honor of Dr. Blanca León, of the Universidad Nacional Mayor de San Marcos and the University of Texas, a generous and accomplished botanist whose many contributions include ecological and taxonomic study of Rio Abiseo National Park.
Phenology. Collected in March and July. A mild dry season occurs June to August (Young and Leon 1988).
Distribution. Endemic to Peru, San Martín, Prov. Mariscal Caceres, Rio Abiseo National Park. (Fig. 6) Habitat. From high-elevation grasslands, at 3450-3800 m. Young and León (1988) compare the habitat to the wet páramos of southern Ecuador, and note that the U-shaped valleys at high elevations where this variety was collected were glaciated as recently as 12,000 years ago.
Conservation status. Endangered, Criteria B1ab(iii) (IUCN 2014). Th is variety is known from only two sites 10 km apart in the protected area of Rio Abiseo National Park In recent years, cattle-grazing, which may have been a threat, has ceased (B. León, pers. comm.) However, the very small distribution, and the fact that this variety represents the southernmost occurrence of a wetland páramo species suggests vulnerability to climate fl uctuations.
Discussion. Th is variety is found at the southernmost and highest elevation station for the species in Peru. It occurs above 3400 m at the very south end of the Amotape-Huancabamba fl oristic zone as characterized by Weigend (2004), in the drainage of the Rio Huallaga. Th is compares to the typical variety collected at up to 3400 m, in the drainage of the Rio Marañón.
Th e uniformly thickened fruiting perianth of this variety is similar to that of P. caryonauta, complicating the otherwise tidy distinction between the two species. However the size and shape of the leaves, the dwarf peduncles, the pale greenish involucres, and the large rigid nectary papillae, all suggest P. pilosus, and the type specimen in particular looks nearly identical to populations of typical P. pilosus from adjacent southern Amazonas. In fact, these populations are partly intermediate in fl oral morphology between the two varieties, as discussed under the typical variety. Given the variation in P. pilosus in Peru and the contiguity of distribution, it seems best for now to treat this taxon as a variety of that species.
Th e specimen Young & León 4368, collected ca. 10 km from the other two, is marked by the very small size (5.5-7 mm) of the dark green leaves. Th e fl owers and seeds are also smaller. Th e habitats of the two localities diff ered, with the type locality a typical patchy wet páramo among outcrops, while the small-leaved plant was in a broad boggy area bordered by small trees, where cattle once pastured (B. León, pers. comm.)  Moldenke (1983) in part, and Rivera-Díaz (2010), probably non Moldenke (1952).
Th is robust taxon has a clumping habit structurally similar to P. pilosus but lacks the dense pulviniform aspect. Its other similarities include acute to aristate leaves, scarious splitting peduncle sheath tips, pale gold lanceolate involucral bracts, and a nearly identical fl ower and fruit morphology. It diff ers by the following characters: Leaves longer, narrowly linear-lanceolate, 3-4 cm long, the peduncles 10-20 cm long at anthesis, and the capitula 6-7.5 mm wide, much more fl oriferous (> 40 fl owers) than P. pilosus and sometimes globose at maturity, with alternating whorls of staminate and pistillate fl owers. In addition, the capitula are "indeterminate," with fl oral primordia found at the center of capitulum at the time of anthesis of the outer whorls. Th is contrasts with P. pilosus, in which pistillate fl owers are limited to the outer whorl, staminate to the inner, and no fl oral primordia are found at the start of anthesis.
Th e most robust individuals are found in the northern part of Serrania del Perija (ca. 10°15'-10°20' N), but similar smaller plants are also found at the north end of the main Cordillera Oriental, about 300 km to the south. Th ese have leaf, peduncle and sheath lengths approaching those of the Perijá plants, and in spite of their small capitula, the fl owers are more numerous than in typical P. pilosus (up to 40 per capitulum), and pistillate and staminate whorls alternate in the capitulum. It isn't clear whether to treat these plants as small individuals of Paepalanthus sp. A, or intermediates with P. pilosus. Smaller individuals are also found at Sa. de Perijá (Cuatrecasas 25027, 25143, US), but were only observed from scans.
Th e plants of Perijá had been distributed in part as P. macarenensis, a species otherwise only known from ca. 800 m in the Sierra de la Macarena (Meta). I have seen an image of the P. macarenensis type, and do not believe it is the same species or closely related, but pending closer examination treat the Perijá plants only provisionally here.  Huft (1994).