Cnidoscolus aconitifolius (Mill.) I.M.Johnst. subsp. aconitifolius

van Welzen, P. C. & Fernández-Casas, F. J., 2017, Cnidoscolus (Euphorbiaceae) escaped in Malesia?, Blumea 62 (1), pp. 84-86 : 84-86

Cnidoscolus aconitifolius (Mill.) I.M.Johnst. subsp. aconitifolius cv. ‘ Chayamansa ’ (McVaugh) Breckon ― Fig. 1 (see note 2)

Cnidoscolus aconitifolius (Mill.) I.M.Johnst. subsp. aconitifolius cv ‘Chayamansa’ (McVaugh) Breckon in Kolt. , Breckon & R.R.Kowal (1984) 24. ― Cnidoscolus chayamansa McVaugh (1944) 466. ― Type: McVaugh 494 (holo US; iso CAS, DS, F, MICH, MO, NY, S), British Honduras [ Belize], Honey Camp.

Jatropha quinquelobata Mill. (1768) Jatropha species n ° 2. ― Cnidoscolus quinquelobatus (Mill.) León (1941) 236. ― Type: not indicated, reference to manuscript by Houstoun; Houstoun s.n., 1730 (BM no. 820455), Mexico, Vera Cruz, is a candidate for lectotypification.

Jatropha fragrans Kunth in Humb., Bonpl. & Kunth (1817) 105. ― Cnidoscolus fragrans (Kunth) Pohl (1827) 63. ― Type: von Humboldt & Bonpland 1333 (holo P no. 669927; iso P no. 545646), Cuba, Havana.

Jatropha urens L. var. inermis Calvino (1919) 364. ― Cnidoscolus aconitifolius (Mill.) I.M.Johnst. subsp. aconitifolius cv.‘Inermis’ (Calvino) Breckon [ Cnidoscolus sect. Calyptrosolen ( Euphorbiaceae ) in Mexico and Central America, nom. inval., PhD thesis not distributed] ex Fern. Casas (2007) 4, nom. illeg. (based on unpublished name). ― Type: Calvino s.n., 5 Dec. 1918 (USNA), Cuba, Santiago de las Vega, cultivada.

Cnidoscolus chaya Lundell (1945) 321. ― Type: C.L. & A.A. Lundell 8201 (holo LL; iso F, LL, MICH, S), Mexico, Yucatan, km 27 Mérida-Progreso Road .

Shrubs, up to 2.5 m high, somewhat succulent; branches up to 9 mm thick when dry, glabrous or locally with bristle hairs, not striate when dry, nodes thickened; juicy with translucent sap. Indumentum of bristle hairs, present in low densities on various organs, and short, woolly hairs in top of inflorescences. Stipules very early caducous, leaving thick, succulent scars. Leaves alternate, simple, concentrated towards the tips of the stems; petiole 6.2–13.5 cm long, not striate when dry, round e when fresh, glabrous, apically with a pair of elevated, touching to partly united extrafloral nectaries; blade 5-lobed, ovate, 11–21 by 9–18.5 cm, lobes overlapping, symmetric, papery when dry, base broadly emarginate, margin laxly serrate in especially the apical lobe parts, short and longer teeth alternating, with short bristle hairs, apices of lobes acuminate; venation basally palmate, pinnate in lobes, secondary nerves looped and touching near margin. Inflorescences terminal, dichasialsubumbelliform; peduncle up to 23.5 cm long, with a few short bristle hairs, especially apically woolly hairs; branches woolly hairy; bracts triangular, c. 1.2 by 0.8 mm, apex acute, outside with woolly hairs; bracteoles like bracts, slightly smaller but with tip transformed into a gland; central flowers pistillate, more terminal/lateral ones staminate. Flowers 5-merous; calyx partly connate, lobes 5, imbricate, petaloid, white, outside woolly hairy, apically a few short bristle-like hairs, inside glabrous; petals absent. Staminate flowers seen in bud; calyx tube c. 4.7 mm long, lobes obovate, c. 2.5 by 2 mm; disc around androphore, indistinct; stamens 10, all united, outer 5 shorter, splitting off in lower part of androphore, with longer free filaments than upper and inner 5, anthers dorsi-basifixed, triangular, seemingly opening introrsely via lengthwise slits; on top of the androphore a pistillode, stigma-like, filamentous. Pistillate flowers 10–11 mm wide; pedicel woolly hairy, lower part of pedicel 1.5–2 mm long, upper c. 1 mm widening and continuing in calyx, persistent when calyx caducous; calyx basal c. 0.5 mm united (above wid- ened part petiole), lobes oblong, c. 7 by 2.2 mm, reflexing; disc gynophore-like, tightly around ovary and staminodes, 5-lobed, c. 0.5 mm high, glabrous, white; staminodes 10, filament-like to stamen-like; ovary 3-locular, ellipsoid, c. 3 by 2 mm, outside smooth, with woolly hairs, a single ovule per locule; style c. 0.8 mm long, glabrous; stigmas c. 3.3 mm long, 2–3 times bifurcate, glabrous. Fruits and seeds unknown because pollen infertile.

Distribution ― The species is native in Mexico and Central America, but the cultivar has a much wider distribution ( Howard 1989). In Malesia only known from four Philippine collections, two cultivated in a garden, one in Manila (Luzon, garden of the collector, M.L. Steiner 1085 = PNH (Steiner) 36973) and in Pasay City (Luzon; PNH (C.G. Manuel) 18631), two collected outside Cebu City (Cebu; D. Bicknell 1546, 1649).

Habitat & Ecology ― Outskirts of Cebu City, along stream. Altitude: 200–250 m. Flowering: June, July .

Vernacular name ― Chaya (Mexican) .

Uses ― Young leaves and shoots are eaten as a vegetable and seemingly rich in vitamin C ( Radcliffe-Smith 2001, in note, as C. chayamansa ). This cultivar is edible because the leaf surface is quite large and it hardly has stinging, bristly hairs, which are generally very apparent in most other species in this genus.

Notes ― 1. De Sessé y Lacasta (1794) published Jatropha quinqueloba and J. palmata (non Willdenow 1805; J. palmata Willd. is a synonym of C. aconitifolius subsp. aconitifolius ) in a footnote of a printed speech by Prof. Vincente de Cervantes in the supplement of a Mexican literary newspaper. The journal is obscure, but the descriptions though brief are valid. De Sessé’s J. palmata is older than Willdenow’s name, making the latter illegitimate. A specimen in Madrid, ‘ Herbario de Sessé y Mociño 4230 ’ (MA 602171), shows that J. palmata is a Manihot and the name is not a synonym of Cnidoscolus aconitifolius as suggested by ThePlantList.org (last checked March 2017. Jatropha quinqueloba Sessé (based on ‘ Herbario de Sessé y Mociño 4227 ’, MA 602180), and closely resembling the name J. quinquelobata Mill. , is identified as J. tubulosa Müll.Arg. (anonymous identification), a synonym of C. tubulosus (Müll. Arg.) I.M.Johnst. Both Jatropha names do not appear in the much later published Flora Mexicana by Sessé & Mociño (1892–1898, of which the second edition was partly even printed earlier; not in references!).

2. The figure shows the wild type of C. aconitifolius , which is fertile and of which fruits are known. The cultivar has broader, leafier leaf lobes that largely overlap.

Figures

Fig. 1 Cnidoscolus aconitifolius (Mill.) I.M.Johnst. a. Habit, branch top with leaves and inflorescence; b. partly united pair of extrafloral nectaries at petiole apex; c. stipule with glands in abaxial view; d. stipule with glands in adaxial view; e. staminate bud; f. androecium and disc; g. pistillate flower; h. pistillate petal, abaxial surface; i. gynoecium, disc and staminodes; j. fruit; k. seed in ventral view; l. seed in dorsal view, m. seed in transverse section; n. seed in ventral view; o. seed in dorsal view; p. seed surface (a–i, n: T. Flynn 3319, BISH; j, o–p: R.L. Wilbur 27657, DUKE; k–m: C.L. Lundell 8201, MICH, type of C. chaya). ― Drawing: J.L. Castillo, 2006.