Hodgsonia.

Hodgsonia Hook.f. & Thomson
Hodgsonia Hook.f. & Thomson, Proc. Linn. Soc. London 2: 257. (‘1853’), 1854.
Type: Hodgsonia heteroclita (Roxb.) Hook. f. & Thomson; basionym: Trichosanthes heteroclita Roxb., Fl. Ind. 3: 705. 1832; holotype: drawing no. 2399 of Roxburgh (K), plant grown in Calcutta Botanical Gardens, originally from Silhet, East Bengal, India.

Large liana with up to 30 m long, woody stems and dioecious sex system. The leaves are simple, petiolate, with thorn-like, c. 5 mm long probract at the base of the petiole and subcircular, palmately 3-5-lobed blade, up to 25 cm in diameter. The tendrils are bi-or trifid. The flowers are large, fragrant and open at night. Male flowers are produced in bracteate, pedunculate racemes, the female flowers solitary or rarely in short racemes. The receptacle-tube is elongate, to 12 cm long, apically dilated into a shallow cup with five small (1-4 mm long) sepals. The corolla is rotate with five cuneate, to 5 cm long, white to yellowish petals, long-fimbriate, each with 5–15 cm long, spiraling or straight threads. The three stamens are inserted in the upper half of the tube on distinct short filaments. Two anthers are bithecous, one monothecous, connate into a globose head. The thecae are duplicate and contain tricolporate, coarsely reticulate, very large pollen (polar axis c. 158 µm, equatorial axis 148 µm, (Khunwasi 1998)). The ovary is subglobose, secondarily tricarpellate and hexalocular. The six placentae contain 6 or 12 erect or pendent ovules in 6 collateral pairs. The style is filiform with large, obconical, trilobed stigma. The fruit is a large, pulpy, hard-walled, drupe smooth or shallowly 6-12-grooved, depressed globose, to 25 cm across, with six large, simple or compound, ovoid, veined pyrenes. Each pyrene contains 1-3 compressed, large, corky seeds. The chromosome number is n=9 (Chen 1993).

Three species in in lowland and lower montane forest, and on riverbanks of Northeast India, Bhutan, South China, Myanmar, Laos, Cambodia, Vietnam, Thailand, Malaysia, and Indonesia. Hodgsonia macrocarpa is sometimes cultivated for the seeds. Named after the British naturalist Brian Houghton Hodgson (1801-1894).

Phylogenetically, Hodgsonia is most likely the sister group to Trichosanthes plus the New world Sicyoeae (Bellot et al., in press).

Accepted species

Hodgsonia heteroclita (Roxb.) Hook.f. & Thomson, Proc. Linn. Soc. London 2: 257. 1853.

Hodgsonia macrocarpa (Blume) Cogn., Monogr. Phan. 3: 349. 1881.

Hodgsonia tsaii J.Y.Shen, X.D.Ma, W.G.Wang & B.Pan, Taiwania 67: 465. 2022.

Literature

Bellot, S., Mitchell, T.C., and H. Schaefer. 2020. Phylogenetic informativeness analyses to clarify past diversification processes in Cucurbitaceae. Scientific Reports 10: 488. doi: 10.1038/s41598-019-57249-2.

De Wilde, W.J.J.O. and B.E.E. Duyfjes. 2001. Taxonomy of Hodgsonia (Cucurbitaceae), with a note on the ovules and seeds. Blumea 46: 169-179.

Khunwasi, C. 1998. Palynology of the Cucurbitaceae. Doctoral Dissertation Naturwiss. Fak., University of Innsbruck.