Begonia cucullata Willdenow (1805: 414)

Martín, Claudia M., Ospina, Juan C. & Zanotti, Christian A., 2017, Nomenclature issues into southern of South American species of Begonia (Begoniaceae), Phytotaxa 314 (1), pp. 129-134 : 130-132

Begonia cucullata Willdenow (1805: 414) .

Type:— BRAZIL. Habitat in Brasilia, s. coll, s.n. (holotype? B-W 17567!).

Begonia subcucullata De Candolle (1903: 404) . Type:— PARAGUAY. ‘Prope Tobaty, in silva’, September 1900, E. Hassler 6130 (lectotype G 00077043! designated here, isolectotypes G 000858173!, G 00077044!, G 00085172!, NY 01842799!, K 000323040!, UC 941383!, MICH 1210021!, GH 00068282!, B 100247922!, BM 000548895!, S 12-17545!). Syn. nov. .

Begonia cucullata var. arenosicola (C. DC.) Smith & Schubert (1941: 106) . Basonym: Begonia subcucullata var. arenosicola De Candolle (1903: 404) . Lectoype:— PARAGUAY. [Itapúa]: Bellavista, (Apa), 1901–1902, E. Hassler 7884 (lectotype G 00077046 [two sheets]! designated here, isolectotypes B 10 0247923!, G 00077041!, G 00085174!, G 00085175!, GH 00068284!, NY 01842798!, UC 941384!). Syn. nov. .

Taxonomic notes: —De Candolle cited two syntypes in the protologue of B. subcucullata , (In rivulis et stagnis pr. Altos, Jan., n. 1771; in locis humidis in silva in colle Tobaty, Sept., n. 6130). We chose the specimen Hassler 6130 (G 00077043!) as lectotype for B. subcucullata , because it presents a higher number of duplicates in different herbaria and bears the original label with De Candolle’s handwriting in 1903. This specimen was mounted on two sheets and represents a unique specimen of this collection ( Gautier et al. 2016).

The original description of B. subcucullata var. arenosicola reads ‘Herba 0.5–0.8 m. alt., petala dilute rosea, in arenosis salsis pr. Bellavista (Apa), Nov., n. 7884’. Four specimens corresponding to Hassler 7884 were found in G. We chose the specimen G 00077046 as a lectotype for B. subcucullata var. arenosicola , because it shows a plant that has a 12 mm thick stem (diagnostic character used to propose this new variety), it is the most complete specimen, and bears the original label with and De Candolle’s handwriting in 1903. Among the specimens corresponding to Hassler 7884, we note that the sheet G00077041 is labeled by G. Marin Ojeda ‘treating this specimen as the type’, but this nomenclatural action was not made effectively.

B. subcucullata var. arenosicola was proposed by De Candolle (1903) based on the thickness of the stem (12 mm in dry material), and the shape of the tepals (rounded) of the female flowers. The thickness of the stem is not a constant character among the type specimens, because this feature is extremely variable, ranging from 5–6 mm wide in the isolectotypes and 12 mm in the lectotype. In addition, the thickness of the stem agrees with the protologues of B. subcucullata , and the shape of the tepals of the female flower is similar to the typical variety. However, the characters described for B. subcucullada var. arenosicola and B. subcucullata correspond to the original description and type specimen of B. cucullata . For these reasons, we propose B. subcucullada and B. subcucullada var. arenosicola as news synonyms of B. cucullata .