Cionosicys Griseb., Fl. Brit. W. I. 288. 1860; corrected to “Cionosicyos” by Hook.f. (1867) but this seems to have been unnecessary.
Type: Cionosicys pomiformis (Macfad.) Griseb.; basionym: Trichosanthes pomiformis Macfad., Fl. Jamaica 2: 143. 1837 ; H.R. Wullschlägel 839 (M), Jamaica, Fairfield.
Perennial climber with several meters long, herbaceous or woody shoots and monoecious sex system. The leaves are simple, petiolate, large, coriaceous, ovate to roundish, entire or trilobed, the tendrils are simple. The large flowers stand solitary in leaf axils. The receptacle-tube is turbinate in male flowers or cup-shaped in female ones. The five sepals are ovate-lanceolate. The funnel-shaped to rotate corolla is composed of five ovate-oblong, greenish-white petals, which are fused at the base. The three stamens are inserted at the base of the tube on free filaments. The anthers are connate into a central column. The triplicate thecae contain triporate, echinate, large pollen (polar axis 103-144 µm, equatorial axis c. 105-146 µm, (Khunwasi 1998)). The ovary contains three placentae with many, ascending to horizontal ovules. The stigmata are strongly papillose. The fruit is a large, ovoid, fleshy, hard-shelled pepo, to 10 cm across, glabrous, ripening yellowish. The many seeds are elliptic, tumid, 1-1.8 cm long with dark brown to black testa.
The four species grow along forest margins and in montane forest in Central America, Cuba and Jamaica.
Phylogenetically, the genus is placed in tribe Cucurbiteae as sister clade to Cayaponia plus Abobra (Schaefer et al. 2009; Schaefer & Renner 2011).
Cionosicys excisus (Griseb.) C. Jeffrey, Kew Bull. 25: 201 1971. [as ‚Cionosicyos‘]
Cionosicys guabubu Grayum & J.A. González, Novon 19: 469 2009.
Cionosicys macranthus (Pittier) C. Jeffrey, Kew Bull. 25: 200 1971. [as ‚Cionosicyos‘]
Cionosicys pomiformis (Macfad.) Griseb., Fl. Brit. W. I. 288 1860.
Grayum, M.H. 2009. Two new trifoliolate-leaved species of Cucurbitaceae (Cucurbiteae) from Central and South America. Novon 19: 465-474.
Khunwasi, C. 1998. Palynology of the Cucurbitaceae. Doctoral Dissertation Naturwiss. Fak., University of Innsbruck.
Jeffrey, C. 1971. Further notes on Cucurbitaceae: II. Kew Bull. 25: 191-236.
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.