Review of the family Rivulidae (Cyprinodontiformes, Aplocheiloidei) and a molecular and morphological phylogeny of the annual fish genus Austrolebias Costa 1998 Author Loureiro, Marcelo Author Sá, Rafael de Author Serra, Sebastián W. Author Alonso, Felipe Author Lanés, Luis Esteban Krause Author Volcan, Matheus Vieira Author Calviño, Pablo Author Nielsen, Dalton Author Duarte, Alejandro Author Garcia, Graciela text Neotropical Ichthyology 2018 2018-10-18 16 3 1 20 journal article 10.1590/1982-0224-20180007 b7b6ef8f-c8e6-43ad-8b21-5450b4090b75 1982-0224 3709839 Cynolebiasini . This tribe is diagnosed by twelve synapomorphies ( Costa, 1998 ): a broad posteroventral process of dentary; concave anterodorsal margin of opercle; anterior position of anal-fin origin in males; elongated filamentous rays on dorsal and anal fins of males; sexual dimorphism in number of dorsal- and anal fin rays; numerous anal-fin rays in males (19–32); elongated dorsal portion of cleithrum ( Fig. 8c ); absence of posteroventral flange of cleithrum ( Fig. 8c ); ventral tip of cleithrum ventrally directed ( Fig. 8c ); broad anteroventral tip of coracoids; numerous supraorbital neuromasts (12–25); and spawning within substrate ( Costa, 1998 ). Its monophyly is supported also by molecular analyses ( Costa et al., 2017a ; Furness et al ., 2015 ). The tribe is composed of eight genera, with small to large adult body sizes ( 30 to 150 mm SL): Nematolebias Costa , with three medium-sized species (max. 80 mm SL) distributed in coastal basin of southeastern Brazil ; Xenurolebias Costa , with four species with small sizes (max. 30 mm SL) endemic to the Atlantic Forest in southeastern Brazil ; Ophthalmolebias Costa , with six species with small sizes (max. 65 mm SL) distributed in eastern Brazil (Costa, 2010); Simpsonichthys , with nine small-sized species (max. 55 mm SL) distributed in the central Brazil Plateau (Costa, 2010); Spectrolebias Costa & Nielsen , with nine small-sized species (max. 32 mm SL) distributed in the Paraguay , Guaporé, Xingu, Araguaia, and Tocantins river basins (Costa, 2010); Hypsolebias , with fortynine medium-sized species (max. 80 mm SL) distributed in Jequitinhonha, São Francisco, and Urucuia river basins (Costa, 2010); Cynolebias , with twenty two medium to large-sized species ( 50–120 mm SL) distributed in the São Francisco and Urucuia river basins (Costa, 2010); Austrolebias , with fortyeight small to large-sized species ( 35–150 mm SL) distributed in the La Plata, Patos-Merin, and southwestern Amazon basins ( Loureiro, de Sá, 2016 ; Costa et al ., 2017a ; Volcan et al ., 2017 ; Alonso et al ., 2018 ). According to a recent molecular phylogenetic analysis ( Costa et al ., 2017a ), Nematolebias + Xenurolebias are the sister clade of the remaining genera, which relate to each other as follows: Spectrolebias , ((( Austrolebias , (( Simpsonichthys , Cynolebias ), ( Opthalmolebias , Hypsolebias ))). However, Ponzetto et al . (2016) , in a phylogenetic analysis based on one mitochondrial marker, had recently challenged the monophyly of Hypsolebias , with some species more closely related to Ophtlamolebias than to other Hypsolebias .