Stickmannia pubescens (Martius ex Schultes f.) Kuntze (1891: 721)

Aona, Lidyanne Yuriko Saleme, Bittrich, Volker & Amaral, Maria Do Carmo E., 2018, Taxonomic and nomenclatural notes on Brazilian Dichorisandra (Commelinaceae), Phytotaxa 348 (1), pp. 1-13 : 8-9

10. Dichorisandra pubescens Martius ex Schultes f. (1830: 1186) .

≡ Stickmannia pubescens (Martius ex Schultes f.) Kuntze (1891: 721) , syn. nov.

Type:— BRAZIL. Habitat in sylvis primaevis utique Provinciae Sebastian op. Flos coeruleiy. Dec. Martius s.n. (Lectotype [here designated]: M 0086150!).

= Dichorisandra foliosa Kunth (1843: 112) , syn. nov.

= Stickmannia foliosa (Kunth) Kuntze (1891: 721) , syn. nov.

Type:— BRAZIL. Brasilia meridionalis. s.d., Sellow s.n. (Lectotype [here designated]: B 100347183!, photo available from http://plants. jstor.org/stable/pdf/10.5555/al.ap.specimen.b%2010%200347183).

= Dichorisandra luschnathiana Kunth (1843: 111) . syn. nov.

Type:—Corcovado, Serra dos Organos [sic!]. Luschnath (no original material found).

Neotype (designated here):— BRAZIL. São Paulo: Santo André, Reserva Biológica de Paranapiacaba. 07 February 2007. L. Y. S. Aona 1007 et al. (Neotype: UEC!).

≡ Dichorisandra pubescens Martius ex Schultes f. var. luschnathiana (Kunth) Clarke (1881: 277) . syn. nov.

Distribution: —This species occurs predominantly in southeastern Brazil, but also in Bahia, Goiás, Mato Grosso, Pará, Paraná, and Santa Catarina. Aona (2008) has also reported material from Ecuador, Peru, and Bolivia.

Habitat:—Dense Ombrophilous Forest and Seasonal Semideciduous Forest.

Notes:— Kunth (1843) described D. foliosa (1843: 112) from material collected by Friedrich Sellow (1789–1831), distinguishing it from D. pubescens mainly by the shape of the leaf blade (oval-oblong vs. lanceolate), and noted that it was very similar to D. pubescens . An analysis of each species’ type material showed that they have various characters in common, for example, the number of stamens (six) and dehiscence of the anthers by two apical pores. The type specimen of D. foliosa has smaller leaf blades than the type of D. pubescens , a feature that was not mentioned by Kunth in the description of D. foliosa . Aona (2008) indicated the leaf blade size of D. pubescens is 10–18.5 × 2.7–5 cm while in D. foliosa 4.5 × 1.8–2 cm. The presence of hairs on both surfaces of the leaf in both specimens strongly suggests the size differences only represent the species natural morphological variation. Aona (2008) considered that difference in leaf blade size alone is not sufficient to support the separation of D. pubescens from D. foliosa . Therefore, the formal synonymization of D. foliosa under D. pubescens is proposed here.

The specimen used by Kunth to describe D. foliosa appears to have the date Sellow collected it. The label information “Ded. (dedit) 1836” (i.e. donated in 1836), however, is most certainly related to the date when Kunth received the material in Berlin and included it in his personal herbarium because Sellow died in 1831. This incorrect collection date´1836´is also reproduced in Tropicos.org (2018).

In the same work, Kunth also describes D. luschnathiana based on material collected by Bernhard Luschnath (1831–1883) on Serra dos Órgãos and Corcovado in Rio de Janeiro. We were unable to find original material used by Kunth to describe this species. However, based on characters mentioned in the protologue, such as indument on the sheaths, blades, inflorescence peduncle and sepals, as well as other flower characters (e.g. six stamens), it is evident that this species is indistinguishable from D. pubescens . Clarke (1881) appears to have had a similar opinion because he made D. luschnathiana a variety of D. pubescens , and only cited the characters “ foliis oblongis; petalis obtusis ” in his description based on two Glaziou collections (6993 and 6994) from “Serra dos Organos” (=Serra dos Órgãos, Rio de Janeiro state). From all the species with alternate, distichous leaves, six stamens, and anthers dehiscent by two pores, only D. hexandra and D. pubescens occur in the region of Serra dos Órgãos ( Aona 2008). Further, Aona (2008) examined Glaziou 6994 and noted that it is in fact a specimen of D. pubescens . A more detailed analysis of the type of D. pubescens , as well as of the type of D. luschnatiana , showed that the distribution of the indument on the vegetative parts of D. pubescens is uniform. Indument is a highly variable character in D. hexandra , but is never uniformly distributed on all the plant organs, as it occurs in D. pubescens . Therefore, the synonymization of D. luschnathiana under D. pubescens is proposed.