Curarea Barneby & Krukoff

Ortiz, Rosa del C., 2018, A taxonomic revision of Curarea Barneby & Krukoff (Menispermaceae), PhytoKeys 100, pp. 9-89 : 21-23

Curarea Barneby & Krukoff

Curarea Barneby & Krukoff, Mem. New York Bot. Gard. 22(2): 7. 1971.

Type.

Curarea toxicofera (Wedd.) Barneby & Krukoff.

Description.

Lianas, dioecious, growing in canopies or understory; branchlets villous, strigose or strigillose-tomentellous to glabrate, conspicuously ridged. Leaves simple, spirally arranged; blade narrowly to broadly ovate or elliptic, oblong, broadly elliptic, suborbicular, less frequently obovate; attached to the petiole at the base or scarcely subpeltate, chartaceous to coriaceous, base truncate or obtuse to rounded or slightly cordate, margin entire (or very rarely minutely undulate, weakly lobed or apically bilobed in C. candicans ), apex retuse (cleft), acute or acuminate, rarely mucronulate, often cuspidate in young shoots, surfaces usually discolorous, especially when juvenile, lustrous and glabrous adaxially, but midrib sometimes sparsely tomentose, abaxially with finely silvery tomentellous, strigillose-tomentellous or web-like indumentum or the latter coarse and cream or dark brown villous, sometimes restricted to the areolae with age; palmati- to plinerved, (3-)5-7 main veins, the innermost pair perfect or imperfect acrodromous, secondary veins 0-2(-3) pairs or rarely absent, departing from midrib above the middle of the blade; petiole terete, tomentose to glabrate, pulvinate at both ends, apical pulvinus usually more conspicuous, the surface weakly rugulose, sometimes adaxially flattened. Inflorescences are solitary or fascicled, cauliflorous, axillary, supra-axillary or terminal on young shoots, basically thyrsi or simple dichasia; bracts subtending the primary branches lanceolate, narrowly ovate or ovate, markedly concave, fleshy, glabrous adaxially, variously pubescent abaxially, indument appressed or spreading. Staminate inflorescence with the axes sometimes conspicuously ridged; primary branches either lax, with several branching orders or compact and with few branching orders, pauci or multiflowered, variously pubescent. Pistillate inflorescences, with primary branches consisting of simple dichasia or these reduced to single flowers, mostly pauciflorous. Flowers are unisexual, actinomorphic and trimerous; pedicels conspicuous (absent in staminate flowers), terete, moderately slender, sometimes ridged, pubescent; bracteoles 1-2(4), usually early caducous, especially in staminate flowers. Staminate flowers are cream, whitish, greenish, yellowish, orangish, greyish or brownish; sepals 6(-9), in 2(-3) unequal whorls (spirally arranged), free, mostly ovate, narrowly ovate to obovate, oblong, rhombic, elliptic or suborbicular, inner whorl larger than outer one, both whorls weakly concave, scarce fleshy, glabrous adaxially and variously densely pubescent abaxially, tip of inner sepals erect or reflexed past anthesis; petals (5-)6 in 2, more or less similar whorls, smaller than the inner sepals, free narrow or broadly obovate-trilobed, obovate-rhombic or spatulate, weakly concave, membranous, glabrous adaxially, glabrous to densely tomentellous abaxially, base cuneate to distinctly clawed, lateral margins weakly to strongly inflexed and partially clasping the filaments, rarely those of the inner whorl adaxially connate, apex acute, obtuse, truncate or retuse; stamens (3-)6 in (1-)2 similar whorls, filaments free or variously connate, clavate, clavate-sigmoid or weakly terete, glabrous adaxially, glabrous or tomentellous abaxially, anthers basifixed, erect or weakly incurved, the connective is frequently thicker adaxially and forms a keel or a hump at the base or at the apex of the anther, less frequently forming a horn-like structure beyond the anthers; thecae latrorsely opening by longitudinal slits, sometimes anthers splitting into two halves (i.e. abaxial and adaxial) due to the reduction of the connective; pistillode 0. Pistillate flowers are green, yellowish or brownish coloured; sepals 6-9 in 2-3 unequal whorls, free, ovate-lanceolate, elliptic, ovate, broadly ovate, oblong or rhombic, glabrous adaxially, pubescent abaxially, tips of inner sepals usually reflexed after anthesis; petals 3(-6), free, spatulate, weakly concave, membranous, glabrous adaxially, glabrous to sparsely tomentellous abaxially; staminodes 0; carpels 3(-4), tomentose, free, sometimes proximal half coherent when young, style slightly tapering distally, stigma inconspicuous. Infructescences sometimes lenticellate or with the bark exfoliating; fruiting pedicels weakly clavate or terete, at times inconspicuous; carpophores are elongated and terete in understory species or short and subglobose in canopy species (drum-like in C. candicans ). Drupelets oblongoid, ellipsoid, broadly obovoid or subglobose, sometimes weakly flattened laterally, sessile or rarely gradually narrowing toward the base, thus rarely forming a short stipe; stylar scar basal and frequently conspicuous; exocarp thin to thick (including the several layers immediately beneath the epidermal layer), coriaceous when dried, smooth, rugulose or muriculate, densely pilosulose, velutinous to glabrate, dull orange to yellow when ripe; mesocarp mucilaginous; endocarp thin and papyraceous or crustaceous, surface smooth or weakly ribbed along its long axis, less frequently there are also transversal ribs. Seed with endosperm absent, embryo hippocrepiform, cotyledons thick, accumbent, sometimes unequal.

Key to the species of Curarea

1	Abaxial surface of leaf blades covered with coarse, golden, cream, dark brown or greyish tomentellous indumentum	2
-	Abaxial surface of leaf blades covered with finely silvery-tomentellous, strigillose-tomentellous or web-like indumentum	4
2	Staminate inflorescences with primary branches lax, these with (2-)4 or more branching orders	6. C. tecunarum
-	Staminate inflorescences with primary branches compact, these with 0-2 branching orders	3
3	Staminate inflorescences with golden indumentum; drupelets broadly obovoid, weakly laterally compressed, centric or only weakly eccentrically attached; mature leaves broadly ovate to suborbicular; Atlantic Forest in Southeastern Brazil	3. C. crassa
-	Staminate inflorescences with dark brown indumentum; drupelets narrowly obovoid to ellipsoid, laterally compressed, strongly eccentrically attached; mature leaves narrowly ovate to elliptic; foothill forests in Ecuadorian Amazon and eastern Peru	1. C. barnebyana
4	Staminate inflorescences with condensed primary branches; carpophores discoid-shaped	2. C. candicans
-	Staminate inflorescences with lax primary branches; carpophores inconspicuous or elongated	5
5	Staminate flowers with lateral margins of inner petals incurved and connate; stamens frequently 3; drupelets obovoid, ca. 4 × 2.8 cm, on inconspicuous carpophores	5. C. gentryana
-	Staminate flowers with lateral margins of inner petals incurved but free; stamens frequently 6; drupelets ellipsoid or oblongoid, 1.3-3.2 × 0.8-1.8 cm, on conspicuously elongated carpophores	6
6	Staminate inflorescence with filiform primary branches	4. C. cuatrecasasii
-	Staminate inflorescences with moderately stout primary branches	7
7	Staminate inflorescences with rufescent or silvery hispidulous indumentum; drupelets frequently with strongly muriculate surface	8. C. tomentocarpa
-	Staminate inflorescences with greyish or brownish strigillose indumentum; drupelets with relatively smooth surface	8
8	Staminate flowers up to 1.8 mm long, anthers up to 0.3 mm long with connective strongly protruding apically either conically or as a horn, less frequently humped; endocarps 1.7-2.4 cm long	7. C. iquitana
-	Staminate flowers up to 2.4 mm long, anthers up to 0.6 mm long with connective usually not apically protruding or overgrowing as a hump when older; endocarps 0.7-0.9 cm long	9. C. toxicofera