Rivulus

Rivulus
Rivulus cylindraceus (male)
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cyprinodontiformes
Family: Rivulidae
Genus: Rivulus
Poey, 1860
Type species
Rivulus cylindraceus
Poey, 1860

Rivulus is a genus of small freshwater fish in the Cyprinodontiformes family Rivulidae. It was traditionally considered to be the largest genus in its family; however, the genus's size is currently in dispute. Wilson J. E. Costa split this genus into several new genera (including Anablepsoides, Atlantirivulus, Cynodonichthys, Kryptolebias, Laimosemion and Melanorivulus) in 2004 and 2011, leaving only a few Greater Antillean species in Rivulus itself.[1] Despite being moved to other genera, some of the species retain the common name "rivulus", like the well-known mangrove rivulus (Kryptolebias marmoratus). Shortly after the review by Costa, another review authored by J.H. Huber refuted the split, moving the proposed genera back in Rivulus and again making the genus the largest in the family Aplocheilidae.[2]

If the split is recognized, the genus Rivulus only includes three non-annual killifish species from western Cuba (including Isla de la Juventud) and Hispaniola where they inhabit streams, rivers and lagoons from the highlands to the coast.[3][4][5] If the split into multiple genera is not recognized, Rivulus contains more than 150 non-annual killifish species found in fresh and brackish waters of the tropical and subtropical Americas, ranging from Argentina in south to Mexico in north, including the Caribbean region.[2]

  1. ^ Costa W.J.E.M. (2011). "Phylogenetic position and taxonomic status of Anablepsoides, Atlantirivulus, Cynodonichthys, Laimosemion and Melanorivulus (Cyprinodontiformes: Rivulidae)". Ichthyological Exploration of Freshwaters. 22 (3): 233–249.
  2. ^ a b Huber, J.H., 2012. Reappraisal of the Phylogeny of Rivulus and its Allied Focused on External Characters. Killi-Data Series 2012: 9-25.
  3. ^ Ponce De León, José Luis; León, Gunnary; Rodríguez, Rodet; Metcalfe, Cushla J.; Hernández, Damir; Casane, Didier; García-Machado, Erik (2014). "Phylogeography of Cuban Rivulus: Evidence for allopatric speciation and secondary dispersal across a marine barrier". Molecular Phylogenetics and Evolution. 79: 404–414. doi:10.1016/j.ympev.2014.07.007. PMID 25050928.
  4. ^ Silva, Rodet Rodriguez (2015). "Rivulus berovidesi, a new killifish species (Teleostei: Rivulidae) from western Cuba". Zootaxa. 3949 (2): 289–96. doi:10.11646/zootaxa.3949.2.9. PMID 25947808.
  5. ^ Loureiro, M.; R. de Sá; S.W. Serra; F. Alonso; L.S.K. Lanés; M.V. Volcan; P. Calviño; D. Nielsen; A. Duarte; G. Garcia (2018). "Review of the family Rivulidae (Cyprinodontiformes, Aplocheiloidei) and a molecular and morphological phylogeny of the annual fish genus Austrolebias Costa 1998". Neotrop. Ichthyol. 16 (3). doi:10.1590/1982-0224-20180007. hdl:20.500.12008/26301.