Research Article |
Corresponding author: Harold Robinson ( robinsoh@si.edu ) Academic editor: Peter de Lange
© 2015 Harold Robinson.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Robinson H (2015) Notes on the genus Chionolaena in Colombia with a new species Chionolaena barclayae (Asteraceae, Gnaphalieae). PhytoKeys 46: 67-71. https://doi.org/10.3897/phytokeys.46.8976
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A new species and a new record for Chionolaena are recorded from Sierra Nevada de Santa Marta, Colombia adding to the two species of the genus already known from that mountain complex.
Chionolaena , Colombia, Sierra Nevada de Santa Marta, new species
Specimens that had been sent to José Cuatrecasas over the years include many that have remained unidentified and were put aside for later work. One set reported here contained members of the tribe Gnaphalieae from the Sierra Nevada de Santa Marta, in northern Colombia, a still inadequately explored mountain area adjacent to but separate from the Andes. When specimens were first put aside, it was not certain to what genus they belonged. Pseudoligandra Dillon & Sagást. was suspected but Chionolaena DC. and Gnaphaliothamnus Kirpiczn. were possibilities. Recent publications by
In a limited study based on hairs pulled from the leaves of numerous species, a possible unifying character has been observed. The hairs were only pulled, not dissected from the leaves, therefore the structure of the bases cannot be stated with certainty, but one feature was consistent as observed. Each hair from various Chionolaena species had a prominent swollen ring near the base at the point of a septation, and remnants of only one thin-walled cell was seen below the septation. This hair type is illustrated by
In the monograph by
The new records of Chionolaena from the Sierra Nevada de Santa Marta are as follows:
Chionolaena Salicifolia (Bertol.) Nesom, SIDA 19(4): 850. 2001.
Helichrysum salicifolium Bertol. Nov. Comm. Acad. Sci. Bonon. 4: 433. 1840.
Gnaphalium seemannii Sch.Bip. in Seemann, Not, Voy. Herald 309. 1856.
Gnaphalium rhodanthum Sch. Bip. in Seemann, Bot. Voy. Herald 310. 1856.
Chionolaena corymbosa Hemsley, Diagn. Pl. Nov. 2: 32. 1879
Gnaphaliothamnus rhodanthus (Sch.Bip.) Kirpiczn, Trudy Bot. Inst. Akad. Nauk SSSR, ser 1, Fl. Sist. Vyss, Rast. 9: 33. 1950 (type of Gnaphaliothamnus).
Gnaphaliothamnus salicifolius (Bertol.) Nesom, Phytologia 68: 378. 1990.
Chionolaena seemannii (Sch.Bip.) Freire, Ann. Missouri Bot. Gard. 80: 452. 1993.
The synonymy follows
Colombia. Depto. Magdalena, Sierra Nevada de Santa Marta, on trail above San Pedro de la Sierra. Paramo 3900 m, small terrestrial herb, 29 Dec, 1974, ; R.J. Robins & E.J. Kirby 618A (Fielding Herbarium, OXF). R.J. Robins 618B (OXF, frag US)
The specimens differ from Mexican and Central American material examined of the species only in having glabrous achenes.
Colombia. Depto. Magdalena. Sierra Nevada de Santa Marta; alrededores de cabeceras de Río Ancho; Páramo de Macotama, above and west of second lake; above valley of Río Ancho, Sta. 15, alt. 4900-5000 m. On high outcrops of bedrock. Shrub, erect stems branching from woody base, to 20 cm tall, entire stem and leaves and involucre gray, hairy, heads yellowish, dry. 17 Feb. 1959. Harriet G. Barclay & Pedro Juajibioy 7072 (holotype US, isotype COL).
Small shrubs to 20 cm tall. Stems branched distally. Leaves alternate, imbricated, appressed, broadly inserted and membraneous at base; blade oblong. 4 mm long by ca. 1.5 mm wide, coriaceous with narrowly recurved margins, dark green, covered with pale hairs on both surfaces, longer and more yellowish abaxially, abaxial pubescence dense and giving abaxial leaf surface rounded appearance, completely obscuring leaf margins, apex blunt. Infloresence of mostly 1–3 heads at tips of unattenuated branches; heads hemispheric, ca. 7 mm high, to 4 mm wide; pale- tipped involucral bracts ca. 15, narrowly lanceolate, 4–5 mm long. ca. 0.8 mm wide. with distal ca. 1.5 mm usually reflexed and whitish inside, pale pink outside; peripheral functionally female florets ca. 20 or more; corollas reddish, filiform, ca. 3.5 mm long, with pair of minute lobes and small biseriate glands distally; style base enlarged, distal branches filiform, scarcely roughened; achenes ca. 1 mm long; glabrous; pappus bristles ca. 28–30, ca. 4 mm long, bases connate in basal row of cells, tips not or scarcely broadened, apical cells with blunt tips; bisexual florets 3–6; corollas reddish, narrowly funnelform, ca. 3.5 mm long, distally with 5 lanceolate lobes ca. 0.5 mm long; anther thecae ca. 0.7 mm long, with long basal tails, apical appendage oblong-lanceolate, ca. 0.5 mm long, glabrous; style base enlarged, distal branches narrowly lanceolate. acute at tip, papillose on sides and apex; achene ca. 1 mm long, glabrous; pappus bristles ca. 28, connate in basal row of cells, distally broadened with bulging cells.
The species is known only from the single collection by Harriet Barkley and Juajibioy. The species is evidently closest to Chionolaena chrysocoma, also from Santa Marta, which also has appressed imbricated leaves. The new species has much broader leaves with dense pubescence abaxially that makes the abaxial surface seem rounded and completely hides the recurved leaf margins. Although the collector stated the heads were yellowish, the bracts and corollas seem reddish or pink. The differentiated tips of the involucral bracts seem less white than in other members of the genus.
The habit of the new species somewhat resembles that of Chionolaena costaricensis (Nesom) Nesom, but the Costa Rican species has much less densely pubescent leaves that are most often spreading rather than appressed to the stem.
Ingrid Pol-yin Lin of the Dept of Botany is thanked for the image of the holotype of Chionolaena barclayae.