Luffa.
Luffa Mill.
Luffa Mill., Gard. Dict. Abridg. ed. 4. 1754.
Type: Luffa aegyptiaca Mill.; replaced synonym: Momordica luffa L., Sp. Pl. 2: 1009. 1753; Lectotype: Clifford 451, Momordica 3 (BM-000647446), „in Zeylona“ [Sri Lanka]; accepted name Luffa cylindrica (L.) M. Roem.
Trevouxia Scopoli, Intr. Hist. Nat. 1: 152. 1777.
Turia Forssk. Fl. Aegypt.-Arab. 165. 1775.
Climbers or trailers with up to 15 m long, herbaceous shoots and monoecious or rarely dioecious (L. echinata) sex system. The leaves are simple, petiolate, with small, lingulate probract at the base of the petiole. The blade is ovate-cordate, palmately tri- to pentalobed. The tendrils are apically 2-6-fid. Flowers are large, the male flowers are produced in racemes, the female flowers solitary. The receptacle-tube is campanulate with three to five sepals. The five petals are free, entire, yellowish-white to golden yellow. The five stamens are inserted near the mouth of the tube on free filaments. The anthers are all monothecous or two bithecous and one monothecous. The thecae are convoluted and contain tricolporate, perforate or reticulate, medium-sized to large pollen (polar axis 70-110 µm, equatorial axis 70-110 µm, (Khunwasi 1998)). The ovary is smooth, ribbed, tuberculate or spiny with many, horizontal ovules. The three stigmata are bilobed. The brown fruit is dry with fibrous tissue, subglobose to cylindrical, beaked, smooth, ribbed or spiny, operculate. The many seeds are oblong-elliptic, compressed with smooth, blackish testa, with or without a narrow, distinct membraneous border and two oblique bumps above the hilum on each face. The chromosome number is n = 13 in L. acutangula, L. aegyptiaca, and L. operculata (Dutt and Roy 1971, Heiser et al. 1988, Singh 1991, Beevy and Kuriachan 1996).
The eight species (Filipowicz et al. 2013) grow on riverbanks, along forest margins, and on disturbed ground in Africa, Central and South America, and Australia.
Phylogenetically, the genus Luffa is placed in the tribe Sicyoeae (Schaefer & Renner 2011).
Accepted species
Luffa acutangula (L.) Roxb., Fl. Ind. ed. 1832 3: 713. 1832.
Luffa aegyptiaca Mill., Gard. Dict., ed. 8, Luffa no. 1, 1768.
Luffa astorii Svenson, Amer. J. Bot. 22: 256. 1935.
Luffa echinata Roxb., Fl. Ind. ed. 1832 3: 716. 1832.
Luffa graveolens Roxb., Fl. Ind. ed. 1832 3: 716. 1832.
Luffa operculata (L.) Cogn., Fl. Bras. 6(4): 12. 1878.
Luffa quinquefida (Hook. & Arn.) Seem., Bot. Voy. Herald 285. 1856.
Luffa saccata F. Muell. ex I. Telford, PhytoKeys 5: 25. 2011.
Literature
Beevy, S.S. and P. Kuriachan. 1996. Chromosome numbers of South Indian Cucurbitaceae and a note on the cytological evolution in the family. J. Cytol. Genet. 31: 65-71.
Dutt, B. and R.P. Roy. 1971. Cytogenetic investigations in Cucurbitaceae. I. Interspecific hybridization in Luffa. Genetica 42: 139-156.
Filipowicz, N., Schaefer, H. and S.S. Renner. 2013. Revisiting Luffa (Cucurbitaceae) 25 Years after C. Heiser: species boundaries and application of names tested with plastid and nuclear DNA sequences. Systematic Botany 39: 205-215.
Jeffrey, C. 1992. Names of the indigenous neotropical species of Luffa Mill. (Cucurbitaceae). Kew Bull. 47: 741-742.
Khunwasi, C. 1998. Palynology of the Cucurbitaceae. Doctoral Dissertation Naturwiss. Fak., University of Innsbruck.
Heiser, C.B. and E.E. Schilling. 1988. Phylogeny and distribution of Luffa (Cucurbitaceae) Biotropica 20: 185-191.
Heiser, C.B., Schilling E.E. and B. Dutt. 1988. The American species of Luffa (Cucurbitaceae). Syst. Bot. 13: 138-145.
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.
Singh, B.P. 1991. Interspecific hybridization in between New and Old-World species of Luffa and its phylogenetic implication. Cytologia 56: 359-365.
Telford, I.R.H., Schaefer, H., Greuter, W., and S.S. Renner. 2011. A new Australian species of Luffa (Cucurbitaceae) and typification of two Australian Cucumis names, all based on specimens collected by Ferdinand Mueller in 1856. Phytokeys 5: 21-29
