Commelina schomburgkiana Klotzsch ex Seubert (1855: 262)

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 : 108-112

7. Commelina schomburgkiana Klotzsch ex Seubert (1855: 262)

Holotype: — GUYANA. R. H. Schomburgk 490 (B-100247302! [ Fig. 7 ]; isotype K-000363254!).

– Commelina schomburgkiana var. latifolia Klotzsch ex Schomburgk (1849: 1064) , nom. inval. (Arts. 35.1 and 38.1; see also Art. 38.3)

Distribution: —Confirmed occurrences in Guyana (where the type originated from), Paraguay and southern Brazil. Habitat: —Open areas, particularly forest edges.

Conservation status: —Least Concern (LC). This species has a wide distribution in South America and does not seem to be threatened.

Notes: —The authorship of C. schomburgkiana has been erroneously presented in recent literature such as Barreto (1997), Zuloaga et al. (2008) and Hassemer et al. (2016b), and databases such as IPNI (http://www.ipni.org) and Tropicos (http://tropicos.org).

The taxonomic status of C. schomburgkiana , which is part of the C. diffusa group, has until now been confusing because the only reliable character to distinguish it from the latter species is leaf shape; linear-lanceolate in C. schomburgkiana , ovate to elliptic in C. diffusa . However, I discovered another taxonomically informative character. The flowers of C. schomburgkiana have three white and blue staminodes ( Fig. 8 ), whereas those of C. diffusa have two yellow staminodes.

Figures

FIGURE 7. Holotype of Commelina schomburgkiana (R.H. Schomburgk 490, B-100247302). Published with permission of Botanischer Garten und Botanisches Museum Berlin-Dahlem.Available online at: http://herbarium.bgbm.org/object/B100247302.

FIGURE 8. Commelina schomburgkiana in Urubici, Santa Catarina, southern Brazil. A: Spathes and flower. B: Spathe containing mature fruits. Photographs by Luís A. Funez.