Linnaeosicyos H. Schaef. & Kocyan
Linnaeosicyos H. Schaef. & Kocyan, Syst. Bot. 33: 349-355. 2008.
Type: Linnaeosicyos amara (L.) H. Schaef. & Kocyan; basionym: Trichosanthes amara L., Sp. Pl. 2: 1008. 1753; Lectotype figure: Plumier, Descr. Pl. Amer. 86, t. 100, 1693, Santo Domingo, West Indies.
Perennial climber or trailer with up to 6 m long shoots, fleshy rootstock, and dioecious sex system. The leaves are simple, petiolate, the blade reniform to suborbicular, entire to deeply trilobed, the upper side distinctly pustulate with short trichomes on whitish-grey, discoidal, multicellular, cystolith-bearing hairbases. The tendrils are simple and up to 12 cm long. The flowers are produced solitary and open at night, when they are pollinated by hawk-moths (Mitchell et al. 2015). The receptacle-tube is broadly campanulate, in buds up to 20 mm long, glabrous, with narrow-triangular, c. 10 mm long sepals. The five petals are ovate, 30 mm by 12 mm, white with green veins, the margin long fimbriate. The three stamens are inserted 10 mm below the mouth of the receptacle tube on free, c. 1 mm long, glabrous filaments. Two anthers are bithecous, one is monothecous, c. 9 mm long, all connate into a globose head. The thecae are triplicate and contain reticulate, tetracolporate pollen, c. 30 µm in diameter (Schaefer et al. 2008). The ovary is ellipsoidal, c. 25 mm long, with three placentae and numerous ovules. The stigma is trilobed with capitate lobes. The fruit is turbinate to ellipsoidal, green, pendent, 8-12 cm long, 3-4 cm across. The several hundred seeds are linear-oblong, compressed, imbedded in soft, whitish pulp. The testa is yellowish-brown, with distinct, flat margin.
The only species grows among cacti in dry thickets and in dry forests from sea level to 300-400 m on the Caribbean island Hispaniola (Dominican Republic).
Phylogenetically, Linnaeosicyos is sister to all New World Sicyoeae, from which it split about 30 million years ago (Schaefer et al. 2009).
Linnaeosicyos amara (L.) H. Schaef. & Kocyan, Systematic Botany 33: 350-354. 2008.
Mitchell, T.C., Dötterl, S. and H. Schaefer. 2015. Hawk-moth pollination and elaborate petals in Cucurbitaceae: The case of the Caribbean endemic Linnaeosicyos amara. Flora 216: 50-56.
Plumier, C. 1693. Description des plantes de l’Amerique avec leurs figures. Paris, pp. 86-87.
Schaefer, H., Kocyan, A., and S.S. Renner. 2008. Linnaeosicyos (Cucurbitaceae), a new genus for the Caribbean sister group of the New World Sicyeae. Systematic Botany 33: 349-355.
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.