Two New Species of Heteropterys (Malpighiaceae) from Southern South America

Abstract

Heteropterys mulgurae, from Misiones, Argentina, and Parani, Brazil, and H. schulziana, from Salta, Argentina, are described as new, and the distinction of each from its closest sister species is discussed. In the course of treating the Malpighiaceae for the forthcoming Catdlogo de las Plantas Vasculares de la Argentina, I have encountered two new species that require description, and that is the purpose of this brief contribution. Heteropterys mulgurae W. R. Anderson, sp. nov. TYPE: Argentina. Misiones: Dep. San Ignacio, Santa Marfa, 24 Aug. 1946 (fr), G. J. Schwarz 3218 (holotype, LIL). Species affinis Heteropterydis nitidae (Lamarck) DC. sed differt glandulis abaxialibus laminae margine vel usque ad 1 mm intra marginem portatis, petiolo plerumque biglanduloso in dimidio distali, samara usque ad 34 mm longa ala dorsali in costam crassam abaxialem circum nucem extensa, pilis folii samaraeque 0.6-0.8 mm longis relative laxis, et bracteolis 1.5-2 mm longis, ellipticis, lateribus saepe revolutis. Woody vine; stems initially sericeous, gradually glabrescent during the first year, developing whitish punctiform to somewhat elongated lenticels, the axillary buds sericeous with dark brown hairs. Lamina of larger leaves 9-15.5 cm long, 3.3-6 cm wide, narrowly elliptical or slightly ovate or obovate, cuneate to nearly rounded at base, broadly obtuse to rounded or emarginate and often apiculate at apex, bearing a row of 5-20 small glands from base to apex along abaxial margin or within 1 mm of margin, adaxially initially sericeous but soon quite glabrate, abaxially densely and persistently metallicsericeous with a continuous underlayer of white hairs and a thinner overlayer of brown hairs, the longer hairs 0.6-0.8 mm long, straight, + strongly appressed, the principal lateral veins 7-10 pairs, more prominent below than above, the fine reticulum visible above; petiole of larger leaves 9-12 mm long, persistently sericeous, mostly biglandular between middle and apex (eglandular in Hatschbach 52790); stipules 0.5-0.7 mm long, triangular, borne on very base of petiole. Inflorescence terminal and axillary, paniculate, sericeous or loosely sericeous to glabrescent in age; flowers borne ultimately in umbels of (3-)4-5(-6) flowers, occasionally with an additional pair of flowers borne more proximally; bracts 1.5-2 mm long, elliptical, erect to spreading, eglandular, abaxially sericeous, adaxially glabrous, persistent; peduncle 3.5-9 mm long, sericeous or glabrescent in age; bracteoles like the bracts but more rounded distally and often somewhat revolute at sides, borne at apex of peduncle; pedicel 4-6 mm long, sericeous or glabrescent in age. Sepals somewhat loose in bud, strongly appressed in anthesis, 1.2-2 mm long beyond glands, 1.7-2.5 mm wide, triangular and obtuse or rounded at apex, abaxially densely and persistently golden-sericeous or appressed-tomentose over the whole surface to glabrescent in fruit, adaxially glabrous, the lateral 4 bearing 8 glands 1.7-2.5 mm long, elliptical or slightly ovate, distally detached and eventually spreading. Petals yellow, strongly reflexed in anthesis, glabrous or with a few appressed hairs on abaxial rib, the claw 1-1.5 mm long, the limb 3-3.5 NovoN 8: 215-217. 1998. This content downloaded from 157.55.39.64 on Fri, 22 Jul 2016 04:18:38 UTC All use subject to http://about.jstor.org/terms