Additions and corrections to the systematics of mayfly species assigned to the genus Callibaetis Eaton 1881 (Ephemeroptera: Baetidae) from South America Author Cruz, Paulo Vilela Author Salles, Frederico Falcão Author Hamada, Neusa text Zootaxa 2017 4231 4 500 534 journal article 36559 10.11646/zootaxa.4231.4.2 fb0a7416-8d2e-4793-9dc3-525ffccb9e62 1175-5326 292674 99D539A1-D4BF-48C4-AEE1-0CA8F198C631 Callibaetis gregarius Navás 1930 nomen dubium ( Figs. 3 A–3G) Callibaetis gregarius Navás 1930a : 72 ; Gillies 1990 : 24 ; Domínguez et al. 2006 : 113 ; Cruz et al. 2014: 29. FIGURE 2. Callibaetis ( Abaetetuba ) capixaba imagoes and nymphs. A. dorsal view of male imago; B. ventral view of male imago; C. dorsal view of male imago; D. ventral view of male imago; E. abdomen of nymphal exuvia; F. genitalia; G. labrum (from nymphal exuvia of holotype) (left d.v., right v.v.). FIGURE 3. Callibaetis gregarius nomen dubium imagoes (types). A. labels (MZB); B. dorsolateral view of male subimago (MZB); C. labels (Senckenberg); D. dorsal view of male subimago (Senckenberg); E. labels (Senckenberg); F. detail of abdomen in lateral view (Senckenberg); G. dorsal view of male subimago (Senckenberg). Known stages. I ♂ Comments. The specimen studied at the Museu de Zoología de Barcelona ( Figs. 3 A and 3B) is not a male imago, as indicated by Gillies (1990) , but rather a male subimago in very poor condition. Other specimens are available in the Senckenberg Deutsches Entomologisches Institut Müncheberg ( Figs. 3 C–3G), but they are also male subimagoes in poor condition. Even if additional specimens of this species could be obtained, the inadequate description, the very poor condition of the type and the vagueness of the type locality would probably minimize the possibility of a reliable identification. Based on our re-evaluation of the morphological and other evidence, we propose that Callibaetis gregarius be classified as a nomen dubium . Material examined. Callibaetis gregarius , male subimago (labeled as type ) and one male subimago, BRAZIL , Ypiranga , 19.iv.1910 , MZB ; three male subimagoes (labeled as syntypes ) same data, Senckenberg. Distribution. Brazil : São Paulo .