A New Dalechampia L. (Euphorbiaceae) from Southern Costa Rica

Abstract

A new species of Dalechampia L. (Euphorbiaceae) with 5-foliolate leaves is described from southern Costa Rica, compared with its closest relative, and illustrated. RESUMEN. Una nueva especie de Dalechampia L. (Euphorbiaceae) con hojas 5-folioladas, se describe de la regi6n sur de Costa Rica, se compara con otra especie cercana y se ilustra en este artfculo. Dalechampia L. is a genus of about 115 mostly neotropical species (Burger & Huft, 1995). Eleven species have recently been accounted for in Costa Rica (Burger & Huft, 1995). Except for D. spathulata (Scheidweiler) Baillon, an erect subshrub, the Costa Rican taxa are clambering vines with leaves that vary from simple and unlobed, with 5 palmate veins, to 2-3-lobed, and to trifoliolate. A new Dalechampia with 5-foliolate leaves from southern Costa Rica is described below. Dalechampia burgeriana G6mez-Laurito, sp. nov. TYPE: Costa Rica. Puntarenas. Coto Brus, Fila Cruces, entrada de los Atunes y orilla de la quebrada, borde de bosque, pastizales y charrales, 1000-1200 m, 24 July 1995, Isidro Chacdn 279 (holotype, USJ; isotypes, CR, F, MO). Figure 1. Dalechampia regnellii species brasiliensis affinis, a qua imprimis differt basi asymmetrici foliolorum lateralium, stipulis involucralibus 8-10 mm longis, bracteis involucralibus majoribus, sepalis pistillatis 12, ovario glabro, fructu majore. Clambering vines, leafy stems 1-1.3 mm thick, with retrorse appressed hairs and spreading stinging bristles 1-1.5 mm long; stipules 8-10 mm long, 1.5-2 mm wide at the base, narrowly lanceolate, ciliate along the margin, with 6-7 ascending veins, persisting. Leaves 5-foliolate, petioles 3-10 cm long, ca. 1 mm thick with retrorse appressed hairs and spreading trichomes, stipels stipule-like; petiolules 3-10 mm long with antrorse appressed hairs; leaflets with blades 6.510.5 cm long, 2-2.5 cm wide, narrowly ellipticoblong to narrowly ovate-elliptic, apex acuminate, margin with short teeth, lateral leaflets asymmetric at the base with a rounded-truncate side and a cuneate side, sparsely pilose on both surfaces, especially on the veins beneath; venation pinnate with 7-8 pairs of major secondary veins. Inflorescence axillary, solitary on axillary short-shoots 47 cm long; short-shoots with retrorse appressed hairs and 1-3 reduced leaves, involucral stipules 8-10 mm long, 1.5-2 mm wide at the base, narrowly lanceolate, pilose along the margin, with 67 ascending veins; involucral bracts 4-5.5 cm long, 3-3.5 cm wide, ovate and 5-lobed, yellowish green, with 7-9 major veins from base, the veins sparsely ciliate outside and strigillose with short appressed hairs on the inner surface, the margin ciliate and with short teeth. Staminate cymules pedunculate, peduncules 3-5 mm long, flattened, sparsely pubescent, involucel cupuliform, 2.5-4 mm long, 6-8 mm wide, with the bracts completely connate; pedicels 3-6 mm long; resiniferous bractlets laminar, margins entire, secreting sticky whitish resin; staminate flowers 8-9; bud oblongelliptic, 2 mm long, 1-1.2 mm broad, acute at tip; calyx lobes 4, becoming reflexed, staminal column 2 mm long, glabrescent, anthers ca. 12, crowded, subsessile, 0.8 mm long, bilocular and dehiscent longitudinally. Pistillate cymules sessile, involucel of 2 bractlets; bractlets glabrous, margins sinuate, densely ciliate with hairs to 1 mm long; pistillate flowers 3, very short-pedunculate at anthesis; peduncles ca. 1 mm long; sepals 12, 3-4.5 mm long, 1-1.5 mm broad, bipinnatifid, margins hispid; ovary ca. 2 mm high, 1.5 mm thick, glabrous, 3locular; stylar column straight, terete, 12-15 mm long, 0.5 mm thick, glabrous, cream-colored, tip slightly dilated and sometimes slightly downturned. Central fruiting-pedicel 2-2.5 cm long, laterals 10-12 mm long; fruiting sepals 12-16 mm long, margins, tentacular processes, and midstrip copiously beset with straight, sharp bristles 1-2 mm long. Capsule 12-14 mm diam., glabrous; columella 12-15 mm long, persisting; seeds globose, ca. 4 mm diam., rugose-verrucate, whitish, palered tinged. This n w species is named in honor of William C. Burge , long-time friend and devoted student of NovoN 10: 368-370. 2000. This content downloaded from 157.55.39.203 on Sat, 10 Jun 2017 18:05:18 UTC All use subject to http://about.jstor.org/terms Volume 10, Number 4 2000 G6mez-Laurito Dalechampia burgeriana from Costa Rica 369 i.. FL_ i: ::: : ??'~:':d