Solena Lour.
Solena Lour., Fl. Cochinch. 477, 514. 1790 (nom. cons.).
Type: Solena heterophylla Lour., J. de Loureiro s.n. (BM), Vietnam.
Karivia Arn. in R. Wight, Madras J. Lit. Sci. 12: 50. 1840.

Perennial climbers or trailers with 2-6 m long herbaceous or woody shoots, tuberous roots, and monoecious or dioecious sex system. The leaves are simple, up to 22 cm long, shortly petiolate to sessile, with ovate or elliptic blade, very variable in shape, base usually cordate but sometimes strongly hastate. The tendrils are simple, glabrous. The flowers are small, male flowers are produced in condensed racemes, the female flowers are solitary, sometimes coaxillary with a male raceme. The receptacle-tube is cup-shaped with five subulate, minute sepals and a 3-4-lobed, conspicuous, fleshy disc. The five petals are free, triangular, yellow or yellowish-white. The three stamens are inserted near the base of the tube on long, free filaments. Two anthers are bithecous, one is monothecous with straight, duplicate or triplicate thecae. The pollen is tricolporate, verrucate, and medium-sized (polar axis c. 63 µm, equatorial axis c. 49 µm (Khunwasi 1998)). The ovary is oblong, glabrous or hairy with few to several, horizontal ovules. The fruit is fleshy, oblong or ovoid, attenuate at both ends, glabrous or hairy, indehiscent, ripening yellow or red. The up to 20 seeds are imbedded in red, sweet pulp, slightly compressed to globose with smooth, greyish-brown testa, sometimes with narrow, corky margin. The chromosome number is n = 12 or 24 in S. amplexicaulis (Beevy and Kuriachan 1996).

The three species are found in thickets and on roadside slopes in Afghanistan, India, Sri Lanka, Myanmar, Malesia, Vietnam, Cambodia and China.

The genus Solena is place in tribe Benincaseae, where it is sister to Borneosicyos and Lemurosicyos (Schaefer et al. 2009, Schaefer & Renner 2011).

Literature

De Wilde, W.J.J.O. and B.E.E. Duyfjes. 2004. Review of the genus Solena (Cucurbitaceae). Blumea 49: 69-81.

De Wilde, W.J.J.O. and B.E.E. Duyfjes. 2006. Redefinition of Zehneria and four new related genera (Cucurbitaceae), with an enumeration of the Australasian and Pacific species. Blumea 51: 1-88.

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

Schaefer, H. and S.S. Renner. 2011. Phylogenetic relationships in the order Cucurbitales and a new classification of the gourd family (Cucurbitaceae). Taxon 60: 122-138.

Schaefer, H., Heibl, C., and S.S. Renner. 2009. Gourds afloat: a dated phylogeny reveals an Asian origin of the gourd family (Cucurbitaceae) and numerous oversea dispersal events. Proceedings of the Royal Society B 276: 843-851.