Aspidosperma macrophyllum Müll.Arg.

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 : 255

Aspidosperma macrophyllum Müll.Arg. in Linnaea 30(4): 397. 1860.

≡ Aspidosperma macrophyllum subsp. macrophyllum . ≡ Paralyxia schomburgkii Baill. in Bull. Mens. Soc. Linn. Paris 1(94): 748. 1888, nom. illeg. superfl. ≡ Macaglia macrophylla (Müll.Arg.) Kuntze, Revis. Gen. Pl. 2: 416. 1891. ≡ Paralyxia macrophylla (Müll.Arg.) Markgr. in Notizbl. Bot. Gart. Berlin-Dahlem 13(119): 458. 1937.

Lectotype (designated here): — GUYANA. [Upper Takutu-Upper Essequibo]: Takutu, Apr 1842, Rich. Schomburgk 547 ( L [barcode L0043163 image!]; isolectotype: RB [fragment] [barcode 00535053!]). B†, F negative No. 4421 image !.

“ Tabernaemontana humboldtii ” M.R.Schomb., Faun. Fl. Brit. -Guian. 2: 40. 1848, nom. nud.

“ Thevetia humboldtii ” M.R.Schomb., Faun. Fl. Brit. -Guian. 3: 1144. 1848, nom. nud.

Notes —The quite intricate rationale behind the Schomburgk brothers’ collections, Robert and Richard was well discussed by van Dam (2002). In short, from the gatherings related to Robert’s second collection series and Richard’s collection series, some bear two collecting numbers (one for each brother) in the same label, but do not always represent the same collection held in the same place. Analyzing the available specimens of A. macrophyllum , we may conclude that Rich. Schomburgk 547 and Rob. Schomburgk 277 are different collections from different places, Takutu and Pirara, respectively.

Regarding the taxon name, some observations may also be made. Baillon (1888) described Paralyxia schomburgkii based on Rich. Schomburgk 547, but Müller-Argoviensis (1860b) presented earlier A. macrophyllum taking into account the same gathering. Aware of this situation, Markgraf (1937) proposed the nomenclatural combination P. macrophylla for recognizing the priority of A. macrophyllum and, also, Paralyxia as a distinct genus. This interpretation was supported by Woodson (1951), but not accepted by Pichon (1947) and Allorge & Poupat (1991), whom accepted A. macrophyllum . In our study, we corroborate the synonymization of Paralyxia in Aspidosperma , since both share morphological diagnostic characters, like the arboreal habit, alternate leaves, coriaceous follicles, and winged seeds.

Finally, since Müller-Argoviensis (1860b) cited explicitly the specimen Rich. Schomburgk 547 from the herbarium B in the protologue of A. macrophyllum , it could be considered the holotype. However, a lectotype must be selected because the B specimen is now destroyed. Thus, we chose the most complete specimen from the single gathering of A. macrophyllum as the lectotype (L barcode L 0043163) (ICN article 9.3; Turland et al. 2018).