Chionolaena barclayae H. Rob., 2015

Robinson, Harold, 2015, Notes on the genus Chionolaena in Colombia with a new species Chionolaena barclayae (Asteraceae, Gnaphalieae), PhytoKeys 46, pp. 67-71 : 69-70

Chionolaena barclayae H. Rob. sp. nov.

Type.

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).

Description.

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.