Jerdonia

Full name and orig. publication: Jerdonia Wight, Icon. Pl. Ind. Orient. 4(2): 10, t. 1352 (Aug. 1848).

Etymology: Named for Surgeon-Major T.C. Jerdon, F.L.S., of the Indian army, an eminent ornithologist. 

Synonyms: -

Infrafamilial position: Didymocarpoid Gesneriaceae - "Basal Asiatic genera” (Weber 2004).

Position: See Notes.

Description: (Sub)acaulescent rosette plants. Leaves long petiolate, lamina elliptic, reticulate. Cymes long-pedunculate (scapose), flowers few, bracts small. Sepals free, lanceolate. Corolla pale lilac with red lines; tube elongate, inflated above; limb oblique, bilabiate, lobes ovate, obtuse. Stamens 4, filaments short, dilated upwards, two with distinct spurs; anthers connivent and apically coherent; thecae divergent, apically confluent. Nectary annular. Ovary ovoid, unilocular, with four parietal placentae; style slender; stigma small, obscurely bilobed. Fruit a broadly ovoid capsule, loculicidally dehiscent, bivalved. Seeds ellipsoid, testa striate-reticulate, with longitudinal furrows (slightly star-shaped in cross section).

Chromosome number: Unknown.

Type and only species: Jerdonia indica Wight

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: SW India (Nilghiri and Anamally Hills). 

Ecology: On rocks in mountains.

Notes: The genus exhibits a number of anomalous features (e.g., isocotylous seedlings, unilocular ovary with four separate placentae, seed anatomy, see Appendix in Weber 1989); its inclusion in Gesneriaceae has been doubted. Burtt (1963, 1977) pleaded for an accommodation in Scrophulariaceae. The molecular data of Möller et al. (2009) clearly plays it at the base of the Didymocarpoid Gesneriaceae.

Selected references: Burtt, Notes Roy. Bot. Gard. Edinburgh 24: 212 (1963); Burtt, Plant Syst. Evol., suppl. 1: 97-100 (1977), syst. pos.; Weber, Bot. Jahrb. Syst. 111: 115 (1989), characters. Möller et al., Amer. J. Bot. 96: 989-1010 (2009), molec. syst.

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

Illustrations:

Jerdonia indica Wight Left: Wight, Icon. pl. Ind. or. 4, t. 1352 (1850), original illustration Right: Wight, Ill. Ind. bot. 2, t. 159b-2 (1850)

last modified: 2007-07-13