Sylvainia M.F.Romero & R.M.Salas, 2023

Romero, Maria Florencia, Gonzalez, Ana Maria & Salas, Roberto Manuel, 2023, Sylvainia, a new monospecific genus within the subtribe Cephalanthinae (Rubiaceae, Naucleeae), Plant Ecology and Evolution 156 (1), pp. 85-111 : 85

Sylvainia M.F.Romero & R.M.Salas gen. nov.

Type species.

Sylvainia natalensis (Oliv.) M.F.Romero & R.M.Salas.

Diagnosis.

Sylvainia differs from Cephalanthus in the plants being erect in open areas to climbing in forests, usually in high lying non-floodable habitats (vs plants erect and associated with waterlogged or periodically inundated habitats); leaves opposite, with leaf domatia in crypts (vs leaves 2-4-verticillate, domatia mostly as tufts of hair, less common as crypts); plants without dark colleters (vs dark colleters present on leaves and stipules, bracts, bracteoles, calyx, and corolla); inflorescences in terminal glomeruli (vs inflorescences thyrsoid, mostly in pleiochasia); corolla tubular, tube internally glabrous, externally reddish, throat greenish, with blackish lobes (vs corolla infundibuliform or hypocrateriform, uniformly whitish), lobes with margins rolled inwards, internally pubescent, tube internally glabrous (vs lobes with margin not rolled inwards, internally glabrous or pubescent, tube internally with a fringe of hairs), stamens with filaments equal or longer than the anthers (vs stamens subsessile); fruit fleshy, endozoochorous (vs fruit dry, schizocarpic, autochorous or hydrochorous); seeds with an aril shorter than half the length of the seed (vs aril longer than the length of the seed).

Etymology.

The genus is dedicated to Dr Sylvain G. Razafimandimbison, a specialist of Rubiaceae , especially of the tribe Naucleeae .