Two New Species of Aeschynomene (Leguminosae: Papilionoideae) from Brazil

Abstract

Summary. Aeschynomene simplicifolia and A. graminoides, two new species from Goias, Brazil, are described and illustrated. A simplicifolia is the only known unifoliolate member of the genus and A. graminoides is apparently aphyllous. During a visit to the herbarium of the Royal Botanic Garden, Edinburgh in May 1990, Dr. Jim Ratter brought to my attention a bundle of unidentified South American legumes. Amongst these I found a striking unifoliolate, pyrophytic herb evidently belonging to the genus Aeschynomene and closely related to A. genistoides (Taub.) Harms, also from Goias, and to A. carvalhoi G. P. Lewis from Bahia, both currently placed in Rudd's Series Pleuronerviae. Later the same year, while visiting herbaria in Brasilia, I spent some time attempting to trace duplicate material of the collection at Edinburgh but without success. As the only other known material of this new species is without either flowers or fruits, the Edinburgh specimen represents an apparently unicate collection of material that must be selected as the type. Aeschynomene simplicifolia G. P. Lewis sp. nov., affinis A. genistoidis (Taub.) Rudd sed foliolis unifoliolatis, haud acicularibus, floribus majoribus differt. Typus: Brazil, Goids, Gifford & da Fonseca G 241 (holotypus E). Erect pyrophytic herb to c. 20 cm tall, with many shoots arising from a woody root; stems longitudinally ribbed, densely spreading-pubescent with whitish hairs, these darker near to the base and with a tendency towards becoming glandular, also a few, scattered, longer (to c. 1 mm long) patent, swollen-based glandular hairs intermixed in the pubescence. Leaves unifoliolate; stipules persistent, lanceolate to narrowly triangular or subulate, 5-9 mm long, 1-2 mm wide at the base, striate, spreading-pubescent; petiole 5-12 mm long with a swollen pulvinus at its base, broadened into a disc-shaped pulvinus at the apex, densely pubescent with swollen-based glandular hairs intermixed; leaflets elliptic to narrowly obovate, 3 3 - 4 - 5 x 1- 3- 1-8 cm, apiculate, symmetric at the base, glabrous on both faces (the blade very finely and obscurely pellucid-dotted at x 20 magnification), the venation prominently raised on both faces, the midvein central, the margin entire, thickened into a prominent marginal vein, the secondary venation tending to be ? brochidodromous on the lower % to 34 of the blade but the upper 2 to 3 secondaries and the basal one linking with the marginal vein. Inflorescence a terminal raceme, c. 4-10 cm long, 3-4-flowered; indumentum