Disynaphia megapotamica (Spreng.) P.L.R.Moraes, comb. nov.

Basionym: Chrysocoma megapotamica Sprengel (1826: 424) .

Type:— BRAZIL. Ad fl. magnum. (Rio grande Amer. Austr. Sello.), Rio Grande do Sul, inter Encruzilhada et Caçapava, Nov–Dec 1825, Sellow 3124 (lectotype P02671867! ex Herb. Sprengel 423, right-hand specimen, designated here; isolectotype P02671867!, left-hand specimen; Fig. 43a) .

Heterotypic synonyms: Eupatorium ericoides Candolle (1836: 150) .

Type:— BRAZIL. Rio Grande, Herbier Impérial du BRÉSIL N.o 843 = Sellow s.n. (lectotype P00742391!, designated here, Fig. 43d; isolectotype G-DC! – G00494074). Syntype: BRAZIL. Rio Grande, Herbier Impérial du BRÉSIL N.o 775 (P02671866!, Fig. 43c) .

Disynaphia ericoides (DC.) King & Robinson (1971b: 124) .

Cortaderia selloana (Schult. & Schult.f.) Ascherson & Graebner (1900: 325) is another name that illustrates a problematic typification in the literature. The basionym, Arundo dioeca Sprengel (1825a: 361) non A. dioica Loureiro (1790: 55), was renamed Arundo selloana Schultes & Schultes (1827: 605) . Gynerium argenteum Nees von Esenbeck (1829: 462) is a nom. illeg. superfl. because Nees von Esenbeck relied on A. dioeca, creating a new name instead of making a new combination with A. selloana . For these names, the original material annotated by K. Sprengel and Nees von Esenbeck was not destroyed at B, which allowed Conert (1961) to assign the nomenclatural types included below with the related synonyms (partially according to Connor & Edgar 1974).