A revised circumscription for the Blakeeae (Melastomataceae) with associated nomenclatural adjustments

Abstract Systematic investigations and phylogenetic analyses of the Blakeeae (Melastomataceae) have indicated that Topobea should be synonymized under Blakea, and Huilaea under Chalybea. Presented here is a detailed description of the Blakeeae, a key to its two accepted genera, and a listing of 62 new combinations, including 3 new names, necessitated by the transfer of Topobea as follows: Blakea acuminata (Wurdack) Penneys & Judd, comb. nov., Blakea adscendens (E.Cotton & Matezki) Penneys & Judd, comb. nov., Blakea albertiae (Wurdack) Penneys & Almeda, comb. nov., Blakea amplifolia (Almeda) Penneys & Almeda, comb. nov., Blakea arboricola (Almeda) Penneys & Almeda, comb. nov., Blakea asplundii (Wurdack) Penneys & Judd, comb. nov., Blakea barbata (Gleason) Penneys & Judd, comb. nov., Blakea brenesii (Standl.) Penneys & Almeda, comb. nov., Blakea brevibractea (Gleason) Penneys & Judd, comb. nov., Blakea bullata (E.Cotton & Matezki) Penneys & Judd, comb. nov., Blakea calcarata (L.Uribe) Penneys & Judd, comb. nov., Blakea calophylla (Almeda) Penneys & Almeda, comb. nov., Blakea calycularis (Naudin) Penneys & Almeda, comb. nov., Blakea castanedae (Wurdack) Penneys & Judd, comb. nov., Blakea clavata (Triana) Penneys & Judd, nom. nov., Blakea cordata (Gleason) Penneys & Almeda, comb. nov., Blakea cuprina Penneys & Judd, nom. nov., Blakea cutucuensis (Wurdack) Penneys & Judd, comb. nov., Blakea dimorphophylla (Almeda) Penneys & Almeda, comb. nov., Blakea discolor (Hochr.) Penneys & Judd, comb. nov., Blakea dodsonorum (Wurdack) Penneys & Almeda, comb. nov., Blakea eplingii (Wurdack) Penneys & Judd, comb. nov., Blakea ferruginea (Gleason) Penneys & Judd, comb. nov., Blakea fragrantissima (Almeda) Penneys & Almeda, comb. nov., Blakea gerardoana (Almeda) Penneys & Almeda, comb. nov., Blakea glaberrima (Triana) Penneys & Judd, comb. nov., Blakea henripittieri (Cogn.) Penneys & Almeda, comb. et nom. nov., Blakea hexandra (Almeda) Penneys & Almeda, comb. nov., Blakea horologica Penneys & Judd, nom. nov., Blakea induta (Markgr.) Penneys & Judd, comb. nov., Blakea inflata (Triana) Penneys & Judd, comb. nov., Blakea insignis (Triana) Penneys & Judd, comb. nov., Blakea intricata (Almeda) Penneys & Almeda, comb. nov., Blakea killipii (Wurdack) Penneys & Judd, comb. nov., Blakea lentii (Almeda) Penneys & Almeda, comb. nov., Blakea longiloba (Wurdack) Penneys & Judd, comb. nov., Blakea longisepala (Gleason) Penneys & Judd, comb. nov., Blakea macbrydei (Wurdack) Penneys & Judd, comb. nov., Blakea maguirei (Wurdack) Penneys & Judd, comb. nov., Blakea maurofernandeziana (Cogn.) Penneys & Almeda, comb. nov., Blakea mcphersonii (Almeda) Penneys & Almeda, comb. nov., Blakea modica (Wurdack) Penneys & Judd, comb. nov., Blakea mortoniana (Wurdack) Penneys & Judd, comb. nov., Blakea muricata (Lozano) Penneys & Judd, comb. nov., Blakea pascoensis (Wurdack) Penneys & Judd, comb. nov., Blakea pluvialis (Standl.) Penneys & Almeda, comb. nov., Blakea sessilifolia (Triana) Penneys & Judd, comb. nov., Blakea setosa (Triana) Penneys & Judd, comb. nov., Blakea standleyi (L.O.Williams) Penneys & Almeda, comb. nov., Blakea stephanochaeta (Naudin) Penneys & Judd, comb. nov., Blakea steyermarkii (Wurdack) Penneys & Judd, comb. nov., Blakea suaveolens (Almeda) Penneys & Almeda, comb. nov., Blakea subbarbata (Wurdack) Penneys & Judd, comb. nov., Blakea subscabrula (Triana) Penneys & Judd, comb. nov., Blakea subsessiliflora (Wurdack) Penneys & Judd, comb. nov., Blakea superba (Naudin) Penneys & Judd, comb. nov., Blakea tetramera (Almeda) Penneys & Almeda, comb. nov., Blakea tetroici (Wurdack) Penneys & Judd, comb. nov., Blakea toachiensis (Wurdack) Penneys & Judd, comb. nov., Blakea trianae (Cogn.) Penneys & Judd, comb. nov., Blakea verrucosa (Wurdack) Penneys & Judd, comb. nov., Blakea watsonii (Cogn.) Penneys & Almeda, comb. nov.


Introduction
Melastomataceae Juss., with approximately 5000 species and 190 genera (Stevens 2001-), is one of the ten largest families of angiosperms. Th e tribe Blakeeae Bentham & Hooker is strictly Neotropical, with centers of diversity in the "megadiverse" Choco-Andean region of South America and the mountains of Costa Rica and Panama, though the species range from Chiapas, Mexico, to the Amazon of Bolivia and Brazil, to French Guiana. Th ree additional species are found in the West Indies. Members of this tribe are notable for their often large, showy fl owers that attract a diversity of pollinators including bees, birds, bats, and rodents (Lumer 1980). Mites and ants live in mutualistic associations in leaf and stem domatia of many Blakeeae (Penneys and Judd 2011). Numerous species in this tribe have great horticultural potential, are relatively easy to grow in temperate zone greenhouses, but are rarely cultivated.
Th e Blakeeae, as historically circumscribed, comprises nearly 200 species in two genera, Blakea L. and Topobea Aubl. However, morphological, molecular, and combined phylogenetic analyses (Penneys et al. 2004;Penneys 2007;Penneys andJudd 2010, 2011, in press) have necessitated adjustments in the circumscription of the Blakeeae. Morphological characters pertaining to the androecium that have been used as a basis for separating these two genera have proven to be homoplasious and of limited taxonomic value (Penneys 2007, Penneys andJudd 2011, Penneys andJudd, in press). Recognition of Topobea renders both that genus and Blakea polyphyletic, thus Topobea is here relegated to synonymy under Blakea. According to Cogniaux (1891), the fi laments in Blakea are thick, while in Topobea they are fi liform. Th e latter character state was found in only three species of Topobea, and even the generotype, T. parasitica Aubl., was not one of them. Th e anthers of Blakea have been said (Cogniaux 1891, Almeda 2000a) to be laterally compressed, while those of Topobea are rounded. Close examination of Topobea anthers proves that they are also laterally fl attened, though since the anthers are generally more subulate, this fact is less apparent than in Blakea (Penneys 2007, Penneys andJudd 2011). Morphological characters synapomorphic for an expanded Blakea include the prevalent but not exclusively hemiepiphytic habit; axillary, nonramifi ed truncate monotelic synfl orescences, fl owers subtended by two pairs of decussate bracts, external calyx teeth lacking, fl owers zygomorphic due to the declinate androecium, and anthers laterally compressed (Penneys and Judd 2011).
Chalybea Naudin and Huilaea Wurdack, were formerly placed in the Miconieae (Naudin 1852, Triana 1871, Wurdack 1957, Judd and Skean 1991, presumably on the basis of their having berry fruits. Morphological and molecular phylogenetic analyses demonstrate that the two genera properly belong in the Blakeeae, forming a clade with ten species sister to Blakea (Penneys et al. 2004, Penneys 2007, Penneys and Judd 2011, Penneys and Judd, in press, Morales-P. 2010, Morales-P. and Penneys 2010. Chalybea has been found to be nested within Huilaea , Morales-P. and Penneys 2010, thus the species in the latter genus will be transferred (Morales-P. 2010, Morales-P. et al., in prep) to Chalybea, which has nomenclatural priority. Th e inclusion of Chalybea in the Blakeeae necessitates an expansion of the recognized morphological variation within the tribe (see below). Th e expanded Chalybea has numerous morphological synapomorphies including the terrestrial, arborescent habit, pinwheel acarodomatia in the vein axils, truncate monotelic synfl orescences with elongate peduncles (Mora-Osejo 1966), actinomorphic, pseudocampanulate fl owers subtended by a single pair of narrow bracteoles, lenticellate hypanthia, anthers laterally rounded and relatively short compared to the fi lament length, inferior ovaries, styles not immersed in a crown, and yellowish-green fruits with thick and leathery exocarps.
In this paper, we present a revised description of the Blakeeae, a key to Blakea and Chalybea with diagnoses of each, and an enumeration of the new names and combinations necessitated by the transfer of Topobea to Blakea. Remarks. Evergreen shrubs, trees, or lianas, growing as terrestrials, hemiepiphytes, or epiphytes, with variable indumentum, the hairs sparsely to densely distributed, unicellular or multicellular, variously smooth to roughened to barbellate, furfuraceous-granulose, eglandular, or sessile to short-to long-stalked globular glandular, setae slender to stoutly conic, occasionally apically fi mbriate. Twigs rectangular, square, quadrate, to terete in crosssection, sometimes formicarial with hollow or apically infl ated internodes and subnodal entrance holes. Stipules absent, interpetiolar and ± coriaceous, or layered and membranaceous. Petioles terete, canaliculate, to winged; leaves opposite, decussate, nearly sessile to petiolate, equal to anisophyllous, then the smaller leaf sometimes deciduous; blade chartaceous to coriaceous, fl at to verrucose, frequently drooping and vivid yellow to scarlet when senescent, the apex acute, to broadly rounded, often abruptly short to long acuminate, the base acute, to rounded, to cordate, rarely subpeltate or decurrent along petiole margins, the margin plane to revolute, entire to toothed; venation acrodromous, basal to plinerved, with prominent midvein and 2 to 7 pairs of secondary veins (including a pair of weak, submarginal veins), tertiary veins numerous and striolate to widely spaced, subperpendicular to midvein; adaxial surface usually glabrescent, but sometimes with persistent hairs (as above), the veins variously fl at to impressed; abaxial surface light to dark green or tan, essentially glabrous to densely pubescent with various hair types (as above), the midvein and major secondary veins raised, minor secondary veins, tertiary veins and higher order veins fl at to raised; acarodomatia frequently present in primary-axillary vein axils, formed by hair tufts, coalesced veins, or membranes, or rarely a foliose fl ap of tissue partially encircling the adaxial apex of the petiole (B. austin-smithii, B. chlorantha). Infl orescences axillary in distal nodes, simple or compound cyme (Chalybea) or solitary to fasciculate (Blakea), bracts and bracteoles caducous (Chalybea) or persistent (Blakea), each fl ower subtended by a single pair (Chalybea) or two (very rarely three) pairs (Blakea) of bracteoles, the bracteoles obscure to foliaceous, membranaceous to coriaceous, free to completely connate, appressed to hypanthium or spreading, linear to elliptic to oblate, entire to remotely denticulate, with pubescence as above. Flowers perfect, 6-merous (4-merous in Blakea tetramera), mostly showy, actinomorphic to zygomorphic as a result of the declinate androecium (Blakea), frequently with pleasantly sweet to musky fragrance (Blakea), rarely nectariferous, the stomatal nectaries located on the anther connective appendages. Hypanthium narrowly to broadly globose, cylindrical to conical, terete to costate, the outer surface glabrous or with pubescence (as above), when present, hairs usually denser proximally, the inner surface glabrous or rarely glandular-pubescent, obscurely to prominently ridged, the apices of the ridges not to distinctly projecting around style base. External calyx teeth, when present, (4-) 6 (absent in calyptrate species), distinct, with apex acuminate to acute, or reduced to blunt thickenings; internal calyx lobes (4-) 6 (absent in calyptrate species), valvate or rarely imbricate, the lobes merely inconspicuous tubercles, to narrowly to broadly triangular, truncate, lanceolate, to orbicular, rarely with a large fl ap of tissue elaborated from the apical and distal portion of the calyx lobe, then tightly held to the underside of the lobe (B. bocatorena ined., B. calycosa, B. tuberculata), the margin entire, often callose-thickened, in fruit, the lobes sometimes becoming colorful, sometimes inrolled; calyx tube glabrous inside. Petals (4-) 6, rarely containing druse crystals, imbricate in bud, orbiculate, ovate, elliptic, obovate, to rhombic, frequently widely so, sometimes clawed, symmetrical or oblique, refl exed, rotate, or pseudocampanulate, white, cream, pink, lavender, magenta, red, or green, the apex acute, obtuse, rounded, truncate, to emarginate; margin entire to minutely erose; both surfaces usually glabrous, rarely sparsely pubescent. Stamens 12 (6 and antesepalous in the hexandrous Blakea clade; 8 in B. tetramera), incurved in bud, isomorphic or rarely subequal with central stamens slightly larger than those at perimeter of cycle (Blakea); fi laments in cross section nearly fl at dorsally, usually with an obscure to prominent ventral keel and laterally narrowed (rarely cylindrical), white, cream, pink, or lavender; anthers white, cream, yellow, bluish, lavender, to deep purple, free or connate, laterally rounded to fl attened, anther sacs somewhat to deeply separated ventrally, linear to obtuse, opening by one or two pores, the pores sometimes confl uent, dorsally to ventrally positioned; dorsal basal anther connective appendages smooth to rugose, mostly modifi ed blunt knobs, parallel longitudinal ridges, triangular spurs (sometimes two present), or caudate. Ovary (2-) 4-6 (-12)-loculate, inferior to superior, apically glabrous or rarely glandular-pubescent, smooth to ridged, unadorned or with circumstylar, short-to long-acute projections, ± rectangular fl anges, or rarely with ascending, radiating, elongate appendages (B. glandulosa, B. hirsuta); placentation axile to deeply intruded axile, the ovules numerous, anatropous; style elongate (bluntly clavate in B. princeps), terete, cylindrical, slightly swollen suprabasally, or tapered, glabrous or glandular-pubescent, white, cream, pink, or lavender; stigma truncate to capitate, rarely obscurely lobed and concave (mostly in Chalybea). Berries ± globose to elliptical, greenish when immature, becoming yellowish-green, pale greenish-white, red, lavender, orange, or deep purple at maturity, glabrous to pubescent (as above), the exocarp thin to leathery, fairly dry and unpalatable to juicy, sweet, and highly comestible (especially Chalybea). Seeds numerous, pyramidal to ovoid, testa smooth to sculpted. Distribution: Mexico (Chiapas) to Bolivia and Brazil; Jamaica, Lesser Antilles. Th e Pacifi c slopes of the Cordillera Occidental, Colombia represent the center of specifi c and morphological diversity. Occurring from sea level to ca. 3000 meters.

Remarks. Phylogenetic analyses
Chalybea includes ten described species of small, South American trees: seven endemic to Colombia, two to Ecuador, and one to Peru. All are found in the Andes, except one species that is restricted to the Sierra Nevada de Santa Marta, Colombia.
For more information on the systematics of Chalybea (and Huilaea), see Lozano-Contreras, G. and N. Ruiz-R. (1996), Morales-P. and González (2005)  Remarks. Blakea is characterized by solitary or fasciculate axillary infl orescences, and fl owers subtended by two (rarely three) pairs of decussate, (usually) expanded, subtending bracts. Additionally, Blakea may usually be distinguished from Chalybea by the species often being hemiepiphytic or epiphytic, mostly with rotate corollas, anthers that are usually laterally fl attened and often connate and/or defl exed, with the connective appendages generally better developed and of diverse morphology, and many Blakea species have ovaries that are not entirely inferior, often possessing stylar collars. Cladistic analyses (Penneys et al, 2004, Penneys 2007, Penneys and Judd 2011) have provided conclusive evidence that the recognition Topobea renders both that genus and Blakea polyphyletic, thus Topobea is here relegated to synonymy under Blakea.
Blakea comprises approximately 180 species distributed from Mexico (Chiapas) to Bolivia and Brazil, with two species in Jamaica and one in the Lesser Antilles.
Formal nomenclatural transfers to Blakea are made below for 62 species of Topobea that were not treated by earlier workers who made similar new combinations (e.g., Don 1823, Macbride 1941). Th ree of these include new specifi c epithets for names already occupied in Blakea.

Probable synonyms not transferred:
Topobea cuspidata Gleason, T. fl oribunda Gleason, T. pubescens Gleason, T. rhodantha L.Uribe, T. rupicola Hoehne are probably synonyms of B. parasitica (Aubl.) D. Don, and so as to not contribute nomenclatural clutter, new combinations will not be made until their status has been confi rmed. Likewise, T. reducta Gleason is likely a synonym of Blakea alternifolia (Gleason) Gleason and will not be transferred until further study.

Ambiguous name:
Topobea andreana Cogn. is not transferred at this time. Th is name is occupied by Blakea andreana Cogn. Th e species is poorly known, but was compared to T. subscabrula Triana by Cogniaux (1887), and to T. grandifl ora Wurdack by Wurdack (1957). Study of the type is needed before a new combination can be proposed.