Commelina vestita Seubert (1855: 264–265)

Hassemer, Gustavo, 2017, Taxonomic and nomenclatural notes on neotropical Commelina (Commelinaceae), and an identification key for Brazil, Guyana, Paraguay, Suriname and Uruguay, Phytotaxa 303 (2), pp. 101-117 : 112

9. Commelina vestita Seubert (1855: 264–265)

≡ Commelina monticola var. vestita (Seub.) Clarke (1881: 162)

≡ Commelina robusta f. vestita (Seub.) Standley & Steyermark (1944: 33)

= Commelina obliqua Vahl (1805: 172) , syn. nov.

Lectotype (designated by Hunt 1994: 172):— FRANCE. Ex horto Celsii, Ventenat s.n. (C-10009563!).

Notes: —The protologue of C. vestita provides the following information about the type: “ Crescit in Brasilia meridionali: Sellow in Herb. Reg. Berol. ”. The type of this name, which was collected by Friedrich Sello in southern Brazil, was most probably destroyed in 1943 when B was bombed. No extant specimens that could be considered original material for this name could be located at B (Robert Vogt, pers. comm.), nor at any other herbaria consulted, and no illustrations were cited in the protologue.

The identity of C. vestita is not completely clear, because the description in the protologue is not informative enough: “foliis oblique ovato-lanceolatis supra scabris utrinque hirtis, vaginis hirtis ore ferrugineo-ciliatis”. Based on this description, C. vestita resemble any of the two South American red-haired Commelina species: C. obliqua and C. rufipes . Barreto (1997: 403) incorrectly regards C. vestita , along with C. monticola Seubert (1855: 264) , a synonym of C. obliqua (see Hassemer et al. 2016b), as a synonym of C. villosa ( Clarke 1881: 183) Clarke ex Chodat & Hassler (1901: 438) . This is incorrect because C. villosa is part of the C. erecta complex, which is morphologically distinct from other red-haired species such as C. obliqua and C. rufipes . Unfortunately the protologue of C. vestita provides no information on the fruits and seeds (“Fructus et semina, quae in hocce Commelinae genere validissimos characteres specierum distinctioni inservientes praebere videntur adhuc ignota”), which could be useful for the application of this name.

Since both Clarke (1881: 162) (who must have seen the type at B) and Standley & Steyermark (1944: 33) regarded C. vestita as an infraspecific taxon of species today considered synonyms of C. obliqua , I here choose to follow their judgement and consider C. vestita as a synonym of C. obliqua . As an additional support to this decision, C. rufipes is not recorded for southern Brazil. Neotypification of the name C. vestita is undesirable, because the area cited in the protologue (southern Brazil, with an area of 576,774.31 km 2) is too vast to permit the selection of an appropriate specimen to link to this name; furthermore, the name C. vestita does not appear to threaten any name in current use.