Monographs Details: Abuta imene (Mart.) Eichler
Authority: Barneby, Rupert C. & Krukoff, Boris A. 1971. Supplementary notes on American Menispermaceae. VIII. A generic survey of the American Tricilisisae and Anomospermeae. Mem. New York Bot. Gard. 22: 1-89.
Family:Menispermaceae
Description:Distribution and Ecology - BRAZIL. Para: basin of Rio Tapajos, Santarem, k m 35 da, estrada do Palhao, M . Silva & R. Souza 2305; Amazonas: basin of the upper Rio Jurua, Froes 21723; Mato Grosso: Rio Arinos, J. G. Kuhlmann 250 (K, NY), 253K (RB), 256K (RB), Dept. Bot. Sao Paulo 8184. COLOMBIA. Amazonas/Vaupes: basin of Rio Apaporis, Garcia-Barriga 13935 (US, COL), 13988 (US—in part), 13990 (US—in part). BOLIVIA. La Paz: basin of Rio Mapiri, 850 m, O. Buchtien 1935 (GH, NY—holotype of Hyperbaena trinervis Rusby). SURINAM. Marowijne Distr., Lindeman & Cowan 6985 (U).This is the first record of the species from the basin of the upper Rio Jurua in the State of Amazonas, from the State of Mato Grosso, and from Bolivia.Garcia-Barriga 13988 and 13990 are mixed collections of Abuta imene and of a Melastomacea.

Discussion:

Hyperbaena trinervis Rusby, Descr. So. Am. PI. 18. 1920.

Abuta trinervis (Rusby) Moldenke in Krukoff & Moldenke, Brittonia 3: 59. 1938.

Abuta klugii Moldenke in Krukoff & Moldenke, Brittonia 3: 64. 1938.

For the use of this species in curare see Mem. N . Y. Bot. Gard. 20(2): 11.

When Hyperbaena trinervis was transferred to Abuta, where it belonged, the authors remarked that there was no known instance of a particular Abuta yielding, in different specimens, different types of androecia, one with filaments all free, the other with all six or the three innermost more or less united (i.e., organically fused) or coherent. Having established this principle, and finding the filaments of A. trinervis all free and separate, of A. klugii (Brittonia 3: 64) all free but coherent, and of A. imene (Brittonia 3: 57-58) dimorphic, the inner three antheriferous and more or less connate and the outer free but variably degenerate, it became mandatory to recognize the three species as distinct, in spite of a close general resemblance in other features. The allied A. selloana was separated at the same time (Brittonia 3: 66) from A. imene and A. klugii by its androecium of six filaments free but coherent, all antheriferous, and from A. trinervis by essentially trivial differences in pattern of leafnerves. Returning to this subject recently [Mem. N. Y. Bot. Gard. 20(2): 10] with the advantages of new collections to work with, we have questioned the supposed difference between coherent and organically fused filaments, an extraordinarily subtle distinction in androecia less than 1 mm in length, and we can categorically deny the rigid intraspecific uniformity of androecia supposed to exist in the genus; on the contrary hardly two androecia of A. imene and A. selloana are precisely alike. Once the androecial character is admitted fallible, nothing substantial remains to distinguish A. trinervis or A. klugii from the widely dispersed Amazonian A. imene.

The diversity now permitted in A. imene raises, however, a new problem; how to distinguish morphologically the allopatric but very closely related A. selloana, confined, as we undertsand it, to extra-Amazonian southern and eastern Brazil, along the south and east slopes of the Planalto, from Parana-Santa Catarina northeast to Ceara. In this connection it should be noted that specimens cited here and collected on Rio Arinos in northwestern Mato Grosso, that is on a stream flowing north to Rio Tapajos, long ago cited by Diels as A. selloana and so accepted by us up to 1970 [cited as Jard. Bot. Rio 53645 in Mem. N. Y. Bot. Gard. 20(2): 13], are here transferred on revision to A. imene, preserving the assumed allopatry of the two species. Since we can no longer rely on the androecium as diagnostic of A. selloana, we have been forced to seek characters, at best rather feeble, in the organization of the staminate panicle and in reticulation of the leaf-blades, set out in key form below. Possibly A. selloana should, certainly it could, be considered a geographic subspecies of A. imene.

Distribution:Brazil South America| Colombia South America| Bolivia South America| Suriname South America|