Austrolebias, Costa, 1998

Alonso, Felipe, Terán, Guillermo Enrique, Alanís, Wilson Sebastián Serra, Calviño, Pablo, Montes, Martin Miguel, García, Ignacio Daniel, Barneche, Jorge Adrián, Almirón, Adriana, Ciotek, Liliana, Giorgis, Pablo & Cascioưa, Jorge, 2023, From the mud to the tree: phylogeny of Austrolebias killifishes, new generic structure and description of a new species (Cyprinodontiformes: Rivulidae), Zoological Journal of the Linnean Society 199 (1), pp. 280-309 : 292-293

Dichotomous key to Austrolebias genus group genera

1a. More than 40 scales in longitudinal series ............................................................................................................................ Titanolebias

1b. Forty or fewer scales in longitudinal series .............................................................................................................................................. 2

2a. In males, presence of iridescent spots longitudinally aligned and usually confluent on the subdistal area of the dorsal fin; presence of iridescent spots on distal portion of pectoral fins ............................................................................................. Argolebias

2b. In males, absence of iridescent spots longitudinally aligned and usually confluent on the subdistal area of the dorsal fin; absence of iridescent spots on distal portion of pectoral fins .............................................................................................................. 3

3a. Suborbital bar absent or inconspicuous and diffuse; preopercular region not covered by scales … Gymnolebias

3b. Suborbital bar present and conspicuously marked; preopercular region not covered by scales (occasionally absent in Acantholebias quirogai ) ................................................................................................................................................................................. 4

4a. In males, basal and medial region of pectoral fins hyaline .................................................................................................................... 5

4b. In males, basal and medial region of pectoral fins not hyaline ............................................................................................................. 7

5a. Flanks of males with regular grey vertical bands on anterior half merging and disappearing towards posterior half ................. ........................................................................................................................................................................................................ Amatolebias

5b. Flanks of males without regular grey vertical bands on anterior half merging and disappearing towards posterior half ........... ........................................................................................................................................................................................................................... 6

6a. In males, urogenital papilla fused to the first anal fin ray or, if not, presence of contact organs in the anal fin ............................. ........................................................................................................................................................................................................ Austrolebias

6b. In males, urogenital papilla not fused to the first anal fin ray or, if fused, absence of contact organs in the anal fin ................... ....................................................................................................................................................................................................... Garcialebias

7a. Subocular bar directed backwards; presence of scales on anterior rostral region of head ............................................ Megalebias

7b. Subocular bar not directed backwards; absence of scales on anterior rostral region of head ........................................................ 8

8a. Presence of ossified contact organs in the anal fin of males ........................................................................................... Acantholebias

8b. Absence of ossified contact organs in the anal fin of males .................................................................................................................. 9

9a. Male pectoral fins not greyish .................................................................................................................................................... Matilebias

9b. Male pectoral fins greyish ........................................................................................................................................................................ 10

10a. Flanks of males with vertical bands ........................................................................................................................................... Acrolebias

10b. Flanks of males without vertical bands ................................................................................................................................. Cypholebias