Didymostigma

Full name and orig. publication: Didymostigma W.T.Wang, Acta Phytotax. Sin. 22: 188 (June 1984).

Etymology: From the Greek διδυμος, didymos = double, twin, and στιγμα, stigma = stigma, referring to the distinctly bilobed stigma. 

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

Description: Annual caulescent herbs with square-angled stem. Leaves opposite, petiolate, lamina ovate, pubescent at both surfaces, serrulate. Cymes axillary; pedunculate; bracteoles similar to leaves in shape; pedicels pubescent. Sepals free to base, linear-lanceolate. Corolla pale purple, tubular-infundibuliform, limb bilabiate, upper lip 2-lobed, lower lip 3-lobed, lobes rounded. Stamens 2, inserted above middle of corolla tube; filaments slightly curved, linear; anthers ellipsoid, basifixed, apically coherent, locules parallel, not confluent; staminodes 2, linear. Nectary cyathiform. Ovary slender cylindrical, loosely pubescent; style slender; stigma bilobed. Capsule slender cylindrical, puberulous, loculicidally dehiscent.

Chromosome number: Unknown.

Species number: 3 [D. obtusum (C.B.Clarke) W.T.Wang, D. leiophyllum D.Fang & X.H.Lu, D. trichanthera C.X.Ye & X.G.Shi]].

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

Type species: Didymostigma obtusum (C.B.Clarke) W.T.Wang

Distribution: SE China (Guangdong, Fujian, Guangxi, Hainan). 

Ecology: In forests on rocks and along trails and roadsides in forested areas; 650-1200m.

Selected references: Feng & Lu, Acta Phytotax. Sin. 32: 565 (1994), new sp.; Wang et al. in Wu & Raven (eds.), Fl. China 18: 292 (1998); Ye & Shi, Havard Pap. Bot. 9: 447-448 (2005), new sp.

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

Illustrations:

Didymostigma obtusum (C.B.Clarke) W.T.Wang, type species Ying T.S. et al., The endemic genera of seed plants in China, Fig. 111 (1993); with permission.

Didymostigma obtusum (C.B.Clarke) W.T.Wang, type species Li Z.Y. & Wang Y.Z., Plants of Gesneriaceae in China, Figs. 1.95 and 1.96 (2004); with permission.

last modified: 2007-07-13