Llanolebias (Hrbek, T. and D. C. Taphorn  2008) 

Description of a new annual rivulid killifish genus from Venezuela.


Abstract: We describe a new genus to accommodate the species originally described as Rivulus stellifer Thomerson & Turner, 1973, but currently referred to the genus Rachovia Myers, 1927. Rachovia stellifer has had a complicated taxonomic history and has, at various times since its description, been placed in and out of three genera: Rivulus Poey, 1860, Pituna Costa, 1989 and Rachovia. However, phylogenetic analyses using 3537 mitochondrial and nuclear characters, and 93 morphological characters indicate it is not a member of any of these genera, but place it as a deeply divergent sister species to the genus Gnatholebias Costa, 1998. In addition to molecular characters, it is distinguished from the genera Rachovia and Gnatholebias by 13 and 33 morphological character states, respectively. 


Llanolebias stellifer (Thomerson & Turner, 1973)

Rivulus stellifer, a new Species of annual Killifish from the Orinoco Basin of Venezuela.

Copeia: 783, figs. 1-2.

Type locality: 1 km north of Caño Benito, on road between El Pao and El Bau, estado Cojedes, Venezuela.

Phylogeny and evolutionary radiation in seasonal rachovine killifishes:

biogeographicaland taxonomical implications               (Costa 2014)



A phylogenetic analysis combining available mitochondrial DNA sequences (total of 3,339 bp) and 161 morphological characters for 22 species of rachovine genera (Aphyolebias, Austrofundulus, Gnatholebias, Llanolebias, Micromoema, Moema, Neofundulus, Pterolebias, Rachovia, Renova, Terranatos, and Trigonectes), and 16 outgroups, supports monophyly of the group containing genera endemic to the Orinoco river basin and adjacent coastal drainages. Results of the present analysis are compared to previous studies. The tree topology indicates that the genera Moema and Rachovia as presently delimited are paraphyletic; consequently, Aphyolebias and Austrofundulus are respectively placed in the synonymy of Moema and Rachovia. This study also indicates that rachovines were in the past geographically restricted to the Amazonas-Paraguay area where diversification in niche exploitation was constrained by competition with sympatric members of older seasonal fish lineages. Rachovines later reached the Orinoco basin and adjacent coastal drainages by dispersal through the Paleo-Amazonas river basin, when major evolutionary radiation taken place.