Senna pendula var. meticola

  • Title

    Senna pendula var. meticola

  • Authors

    Howard S. Irwin, Rupert C. Barneby

  • Scientific Name

    Senna pendula var. meticola H.S.Irwin & Barneby

  • Description

    126l. Senna pendula (Willdenow) var. meticola Irwin & Barneby, var. nov., var. pendulae adspectu simillima sed stylo 4.5-5 (nec 6.5-10) mm longo, filamentis 2 latero-abaxialibus 6-10 (nec 15-20) mm longis, a var. ovalifolia imprimis staminum 2 longiorum antheris crassis 1.5-1.8 (nec 0.9-1.3) mm diam ore grosse dilatatis diversa.—VENEZUELA. Apure: e. outskirts of Puerto Paez, on rio Orinoco at mouth of rio Meta, 17.XII. 1955 (fl), J. J. Wurdack & J. V. Monachino 39964.— Holotypus, NY; isotypus, US.

    Shrubs at anthesis 1.5-3 m, appearing glabrous, the lfts truly so on both faces, the stems thinly puberulent; petiolar gland between first pair of lfts only; lfts (3-)4 pairs, the distal pair broadly oblanceolate or cuneate-obovate 21-31 x 10-14 mm, the camptodrome secondary veins ±7-9 pairs, tertiary venulation faint or 0; longest sepal 9-11.5 mm; longest petal 15-17 mm; filaments of 2 long abaxial stamens 6-8 mm, their anther including beak 7.7-9 x 1.5-1.8 mm, its beak ±1 mm long, strongly constricted proximally and distally dilated into an orifice ± 1 mm diam; style 4.5-5 mm; ovary thinly puberulent; ovules 110-120; pod unknown, but presumably subterete and the seeds 2-seriate.—Collections: 3.

    Wet savannas and riverbanks in lowlands of the middle Orinoco valley, 50-90 m, apparently local on the lower rfos Meta and Guarico in Apure and Guarico, Venezuela.—Fl. IX-II, probably later.

    With its style of moderate length (±5 mm) and two long abaxial filaments (68 mm) about equalling their anther, var. meticola stands intermediate between var. pendula, vicariant westward in Colombia, mostly in the highlands, and the brachystylous, hylaean varieties of the Amazon Basin, all of which have styles only 2-3 mm long. The variety meticola occupies an area of minor endemism from which no other form of S. pendula is known. In cooler submontane climates in western and northern Venezuela S. pendula is represented by the habitally similar var. ovalifolia and var. advena; the latter is quickly distinguished by its slenderly beaked long anthers and the former by a syndrome of 2-3 (not one) petiolar glands and more slender abaxial anthers (±1.3, not 1.5-1.8 mm diam) not dilated at the orifice.