Hoffmannanthus H. Rob., S.C. Keeley & Skvarla, 2014

Robinson, Harold, Keeley, Sterling C., Skvarla, John J. & Chan, Raymund, 2014, Two new genera, Hoffmannanthus and Jeffreycia, mostly from East Africa (Erlangeinae, Vernonieae, Asteraceae), PhytoKeys 39, pp. 49-64 : 56-57

Hoffmannanthus H. Rob., S.C. Keeley & Skvarla gen. nov.

Type.

Vernonia brachycalyx O. Hoffm.

Scrambling shrubs; stems slender with solid pith, somewhat deflected at nodes in upper part of vegetative plant and in inflorescence; hairs of stems L-shaped, with long, multicellular, uniseriate stalk and elongate, horizontal cap cell mounted near one end. Leaves alternate, petioles slender and 7-15 mm long below basal acumination of blade; blades ovate, 6-7 times longer than petiole, 5-10 cm long, 1.5-5.0 cm wide, base broadly obtuse to short-acute, narrowly acuminate at petiole, margins remotely denticulate to nearly entire, apex scarcely to gradually acuminate, surfaces pilosulous and with glandular dots, hairs sparser above, dense on larger veins; secondary veins pinnate, with ca. 6 weak secondary veins on each side of midrib, spreading at ca. 40-45° angles. Inflorescences broadly corymbiform, with branches elongate, mostly with small or insignificant bracteoles at bases; peduncles 2-30 mm long. Heads campanulate; involucre much shorter than florets at maturity; involucral bracts in 2-3 series, persistent, oblong-lanceolate, with acute to short-acuminate tips, puberulous outside, pale at base, midvein broadly greenish, percurrent at tip, lateral margins thinly membranous; receptacle scarcely convex, epaleate, epilose. Florets ca. 15 in a head, homogamous, bisexual; corollas violet to purple, narrowly funnelform, with long basal tube, throat short, lobes narrowly oblong-lanceolate, with glandular dots outside; anthers with triangular apical appendages; base of style slightly enlarged, style shaft glabrous, sweeping hairs on style branches elongate with rounded or blunt tips. Achenes 5-angled, with some glandular dots and short setulae, surface with sparse idioblasts and inner layer with small subquadrate or rounded raphids; pappus pale to sordid or rufous, 2 series, inner pappus of many capillary bristles that are slightly broader in distal half, outer pappus of short narrow scales. Pollen grains 40 µm in diam., Type A, sublophate. 2n = 20 ( Jones 1982, as Vernonia brachycalyx ).

Etymology.

The name Hoffmannanthus is considered appropriate, since both of the older species names featured here were published by Hoffmann (1894, 1895).

Number of species.

The genus contains the single species.