Gaucha Mello-Leitão, 1924

Souza, Maysa F. V. R., Ferreira, Rodrigo L. & Carvalho, Leonardo S., 2021, A new species of the genus Gaucha Mello-Leitão, 1924 from Minas Gerais, Brazil (Solifugae, Mummuciidae), Zootaxa 5061 (3), pp. 559-572 : 561

Genus Gaucha Mello-Leitão, 1924

Gaucha Mello-Leitão, 1924: 140–141 (as Gaùcha [sic]). Type species: Gaucha fasciata Mello-Leitão, 1924 (by original designation).

Gauchella Mello-Leitão, 1937: 84 (synonymized by Botero-Trujillo et al. 2017: 13). Type species: Gaucha stoeckeli Roewer, 1934 (by original designation).

Metacleobis Roewer, 1934: 589 (synonymized by Botero-Trujillo et al. 2017: 13). Type species: Metacleobis fulvipes Roewer, 1934 (by original designation).

Mummuciella Roewer, 1934: 583 , 587 (synonymized by Mello-Leitão, 1937: 84). Type species: Mummuciella simoni Roewer, 1934 (by original designation).

Species composition. Thirteen South American species, namely: Gaucha avexada ; Gaucha cabriola ; Gaucha casuhati Botero-Trujillo, Ott & Carvalho, 2017 ; Gaucha curupi Botero-Trujillo, Ott & Carvalho, 2017 ; Gaucha eremolembra Botero-Trujillo, Ott & Carvalho, 2017 ; Gaucha fasciata Mello-Leitão, 1924 ; Gaucha fulvipes ( Roewer, 1934) ; Gaucha ibirapemussu (Carvalho, Candiani, Bonaldo, Suesdek & Silva, 2010) ; Gaucha mauryi ; Gaucha piranauru sp. nov.; Gaucha ramirezi ; Gaucha santana Botero-Trujillo, Ott, Mattoni, Nime, Ojanguren-Affilastro, 2019 ; and Gaucha stoeckeli Roewer, 1934 .

Distribution. Argentina (Buenos Aires, Córdoba and Santiago del Estero provinces), Bolivia (Cochabamba and La Paz departments), Brazil (States of Bahia, Distrito Federal, Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Pernambuco, Piauí, Rio Grande do Sul, Tocantins), Uruguay (Lavalleja, Río Negro, Rivera).

Diagnosis. Based on Botero-Trujillo et al. (2017, 2019). Members of Gaucha are recognized by the following combination of characters: (i) Cheliceral movable finger MP tooth noticeably large, taller than MM tooth (mostly evident in males). (ii) Cheliceral movable finger mucron of males with gnathal edge carina prominent and convex on lateral aspect. (iii) Cheliceral fixed finger FSD tooth absent, otherwise present only in some specimens, often reduced to the size of a minute denticle in males. (iv) Cheliceral fixed finger of female curved on lateral aspect; angular dorsal crest absent, at most obsolete. (v) Males and females with ctenidia present: sparse on 1st and 2nd postgenital sternites (spiracular sternites I and II); more abundant on 3rd and 4th post-genital sternites (post-spiracular sternites I and II); and one or two ctenidia close to posterior margin of 5th post-genital sternite (post-spiracular sternite III). (vi) Ctenidia filiform, setiform and similar on the five sternites; distinguishable from integumental setae by being longer, single-tipped (non-bifid), and flexible. Additionally, most Gaucha species present sub-ventral whitish bands of the opisthosomal pleural membranes with scattered black marks surrounding the sockets of some setae, with the exception of G. ramirezi , that exhibits an inverse pattern (i.e., white marks on the blackish bands).