Aspidosperma occidentale Malme

Castello, Ana Carolina Devides, Pereira, Andreza Stephanie De Souza, Shimizu, Gustavo Hiroaki, Zuntini, Alexandre Rizzo, Simões, André Olmos & Koch, Ingrid, 2022, Taxonomy and nomenclature of Aspidosperma (Apocynaceae), Phytotaxa 571 (3), pp. 239-277 : 259

Aspidosperma occidentale Malme in Ark. Bot. 21A(6): 10. 1927,

non Aspidosperma occidentale Markgr. (= Aspidosperma tambopatense A.H.Gentry ) in Notizbl. Bot. Gart. Berlin-Dahlem 15(1): 133. 1940, nom. illeg. hom.

Lectotype (designated here): — BRAZIL. Mato Grosso do Sul: Corumbá , 19 Dec 1902, G.O.A. Malme 2732 ( S [No. S04-1790 image!]; isolectotypes: R [barcode R000020532!], S [No. S12-16366 image!]) .

Notes — Malme (1927) indicated the gathering Malme 2732 in the prologue of A. occidentale but did not cite in which herbarium the type would be deposited. Thus, we elected the material with the most informative label from this collection as the lectotype of A. occidentale (S No. S04-1790) (ICN article 9.3; Turland et al. 2018).

Woodson (1951) considered A. occidentale as a synonym of A. australe Müll.Arg. However , A. occidentale has obovate leaves (vs. elliptic to narrow-obovate), flowers with deltoid calyx lobes (vs. oblong), corolla lobes with acute apex (vs. rounded), and sessile follicles (vs. stipitate). Based on this, we consider A. australe and A. occidentale as distinct species.