Crenicichla

Crenicichla is a genus of cichlids native to South America commonly known as the pike cichlids. They are found in most tropical and subtropical freshwater habitats between the Andes and the Atlantic.

Description
The smallest species of Crenicichla (notably members of the C. wallacii species group) are no larger than 6 - 14 cm, and are referred to as "dwarf cichlids" for the aquarium hobby – though their aggressive and territorial habits make them unsuitable for novice keepers. The biggest pike cichlids can grow to about 50 cm long. Most Crenicichla measure in the range of 15 - 30 cm. Like many other predatory fishes, a pike cichlid has a wide mouth and elongated body.

Distribution and ecology
The genus Crenicichla is native to freshwater in tropical and subtropical South America east of the Andes, ranging from Trinidad and the Guiana Shield (including Orinoco), through the Amazon and Río de la Plata Basins, south as far as Río Negro in Argentina. Although widespread as a group, the individual species are often restricted to a single river or river basin. They are found in a wide range of habitats, including rivers, streams, pools and lakes; some species are rheophilic.

The vast majority of pike cichlids are predatory and feed on fish, insects, and other small animals. They usually place themselves where they can stay undetected by the prey, like close to a sunken tree stem or behind a rock. This behavior, as well as the correspondingly adapted shape, which resembles that the unrelated pikes (Esocidae) of the Holarctic, gives the pike cichlids their common name. An exception is C. tapii, which is similar in general appearance to other pike cichlids, but unusual for being gregarious and feeding on periphyton.

Species
There are currently around 93 recognized species in this genus:


 * Crenicichla acutirostris Günther, 1862
 * Crenicichla adspersa Heckel, 1840
 * Crenicichla albopunctata Pellegrin, 1904
 * Crenicichla alta C. H. Eigenmann, 1912
 * Crenicichla anamiri P. M. M. Ito & Rapp Py-Daniel, 2015
 * Crenicichla anthurus Cope, 1872
 * Crenicichla brasiliensis (Bloch, 1792)
 * Crenicichla britskii S. O. Kullander, 1982
 * Crenicichla cametana Steindachner, 1911
 * Crenicichla celidochilus Casciotta, 1987
 * Crenicichla chicha H. R. Varella, S. O. Kullander & F. C. T. Lima, 2012
 * Crenicichla cincta Regan, 1905
 * Crenicichla compressiceps Ploeg, 1986
 * Crenicichla coppenamensis Ploeg, 1987
 * Crenicichla cyanonotus Cope, 1870
 * Crenicichla cyclostoma Ploeg, 1986
 * Crenicichla empheres C. A. S. de Lucena, 2007
 * Crenicichla frenata T. N. Gill, 1858
 * Crenicichla gaucho C. A. S. de Lucena & S. O. Kullander, 1992
 * Crenicichla geayi Pellegrin, 1903 (Half-banded pike cichlid)
 * Crenicichla gillmorlisi S. O. Kullander & C. A. S. de Lucena, 2013
 * Crenicichla hadrostigma C. A. S. de Lucena, 2007
 * Crenicichla haroldoi Luengo & Britski, 1974
 * Crenicichla heckeli Ploeg, 1989
 * Crenicichla hemera S. O. Kullander, 1990
 * Crenicichla hu Piálek, Říčan, Casciotta & Almirón, 2010
 * Crenicichla hummelincki Ploeg, 1991
 * Crenicichla igara C. A. S. de Lucena & S. O. Kullander, 1992
 * Crenicichla iguapina S. O. Kullander & C. A. S. de Lucena, 2006
 * Crenicichla iguassuensis Haseman, 1911
 * Crenicichla inpa Ploeg, 1991
 * Crenicichla isbrueckeri Ploeg, 1991
 * Crenicichla jaguarensis Haseman, 1911
 * Crenicichla jegui Ploeg, 1986
 * Crenicichla johanna Heckel, 1840
 * Crenicichla jupiaensis Britski & Luengo, 1968
 * Crenicichla jurubi C. A. S. de Lucena & S. O. Kullander, 1992
 * Crenicichla labrina (Spix & Agassiz, 1831)
 * Crenicichla lacustris (Castelnau, 1855)
 * Crenicichla lenticulata Heckel, 1840
 * Crenicichla lepidota Heckel, 1840 (Pike cichlid)
 * Crenicichla lucenai Mattos, I. Schindler, Ottoni & Cheffe, 2014
 * Crenicichla lucius Cope, 1870
 * Crenicichla lugubris Heckel, 1840
 * Crenicichla macrophthalma Heckel, 1840
 * Crenicichla maculata S. O. Kullander & C. A. S. de Lucena, 2006
 * Crenicichla mandelburgeri S. O. Kullander, 2009
 * Crenicichla marmorata Pellegrin, 1904
 * Crenicichla menezesi Ploeg, 1991
 * Crenicichla minuano C. A. S. de Lucena & S. O. Kullander, 1992
 * Crenicichla missioneira C. A. S. de Lucena & S. O. Kullander, 1992
 * Crenicichla monicae S. O. Kullander & H. R. Varella, 2015 (Wallace’s pike cichlid)
 * Crenicichla mucuryna R. Ihering (pt), 1914
 * Crenicichla multispinosa Pellegrin, 1903
 * Crenicichla nickeriensis Ploeg, 1987
 * Crenicichla niederleinii (Holmberg, 1891)
 * Crenicichla notophthalmus Regan, 1913
 * Crenicichla pellegrini Ploeg, 1991
 * Crenicichla percna S. O. Kullander, 1991
 * Crenicichla phaiospilus S. O. Kullander, 1991
 * Crenicichla ploegi H. R. Varella, Loeb, F. C. T. Lima & S. O. Kullander, 2018
 * Crenicichla prenda C. A. S. de Lucena & S. O. Kullander, 1992
 * Crenicichla proteus Cope, 1872
 * Crenicichla punctata R. F. Hensel, 1870
 * Crenicichla pydanielae Ploeg, 1991
 * Crenicichla regani Ploeg, 1989
 * Crenicichla reticulata (Heckel, 1840)
 * Crenicichla rosemariae S. O. Kullander, 1997
 * Crenicichla santosi Ploeg, 1991
 * Crenicichla saxatilis (Linnaeus, 1758) (Ring-tail pike cichlid)
 * Crenicichla scottii (C. H. Eigenmann, 1907)
 * Crenicichla sedentaria S. O. Kullander, 1986
 * Crenicichla semicincta Steindachner, 1892
 * Crenicichla semifasciata (Heckel, 1840)
 * Crenicichla sipaliwini Ploeg, 1987
 * Crenicichla stocki Ploeg, 1991
 * Crenicichla strigata Günther, 1862
 * Crenicichla sveni Ploeg, 1991
 * Crenicichla taikyra Casciotta, Almirón, Aichino, S. E. Gómez, Piálek, & Říčan, 2013
 * Crenicichla tapii Piálek, Dragová, Casciotta, Almirón & Říčan, 2015
 * Crenicichla tendybaguassu C. A. S. de Lucena & S. O. Kullander, 1992
 * Crenicichla ternetzi Norman, 1926
 * Crenicichla tesay Casciotta & Almirón, 2009
 * Crenicichla tigrina Ploeg, Jégu & E. J. G. Ferreira, 1991
 * Crenicichla tingui S. O. Kullander & C. A. S. de Lucena, 2006
 * Crenicichla tuca Piálek, Dragová, Casciotta, Almirón & Říčan, 2015
 * Crenicichla urosema S. O. Kullander, 1990
 * Crenicichla vaillanti Pellegrin, 1903
 * Crenicichla virgatula Ploeg, 1991
 * Crenicichla vittata Heckel, 1840
 * Crenicichla wallacii Regan, 1905
 * Crenicichla yaha Casciotta, Almirón & S. E. Gómez, 2006
 * Crenicichla ypo Casciotta, Almirón, Piálek, S. E. Gómez & Říčan, 2010
 * Crenicichla zebrina C. G. Montaña, López-Fernández & Taphorn, 2008

In addition to these, several undescribed species are known.