Deinostigma

Full name and orig. publication: Deinostigma W.T.Wang & Z.Y.Li, Acta Phytotax. Sin. 30 (4): 356 (1992).

Etymology: From the Greek δεινος, deinos = excessive, exceeding, tremendous, and στιγμα, stigma = stigma, referring to the two rather large and equal stigma lobes. 

Synonyms: -

Infrafamilial position: Didymocarpoid Gesneriaceae - "Advanced Asiatic and Malesian genera" (Weber 2004).

Description: Small perennial caulescent herbs. Stem lignescent at base. Leaves alternate, petiolate, lamina ovate or elliptical, with rounded or peltate base, margin repand-crenate. Cymes axillary, pedunculate, 1-2-flowered; bracteoles free, ovate. Sepals free to base, subequal, linear-lanceolate. Corolla white or lilac, tubular-infundibuliform, limb bilabiate, upper lip 2-lobed, lower lip 3-lobed, lobes rounded. Stamens 2, the anterior pair; filaments inserted near middle of corolla tube, thickened in upper part; anthers velutinous, coherent, thecae divaricate, locules apically confluent; staminodes 2. Nectary absent. Ovary short-cylindrical, bilocular, with only one locule fertile; style longer than ovary; stigma with two subequal lobes. Capsule curved, opening only along the dorsal suture.

Chromosome number: Unknown.

Type and only species: Deinostigma poilanei (Pellegr.) W.T.Wang & Z.Y.Li

Species names (incl. publication and synonyms): See Skog, L.E. & J.K. Boggan. 2005: World checklist of Gesneriaceae: http://persoon.si.edu/Gesneriaceae/Checklist.

Distribution: Vietnam (Annam).

Ecology: No details known.

Notes: The genus/species approaches some species of Chirita by the anthers with divaricate and confluent thecae and, in particular, by the ovary with only one fertile carpel. It differs, however, in the lacking nectary, the apically thickened filaments and the stigma with two, equal lobes. From Hemiboea, to which D. poilanei was originally referred (on ground of the ovary structure) Deinostigma differs in the alternate leaves, the small. non-connate bracteoles, the lacking hair ring in the corolla, the thickened filaments, the velutinous, divaricate anthers with confluent thecae, the lacking nectary and the bilobed stigma. According to Wang (1992: 357), the genus "nullius aliis generibus arctius affine et ejus positione systematica obscurum est".

Bibliography: See Skog, L.E. & J.K. Boggan. 2005. Bibliography of the Gesneriaceae. 2nd edition: http://persoon.si.edu/Gesneriaceae/Bibliography.

Illustrations: not available.



last modified: 2007-07-13