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Brief Summary

    Chiapas catfish: Brief Summary
    provided by wikipedia

    The Chiapas catfish, Lacantunia enigmatica, is an unusual species of catfish (order Siluriformes) newly described in 2005 from the Lacantún River in the Mexican state of Chiapas. While discovery of an undescribed species of catfish is not uncommon, discovery of a new family-level taxon of any vertebrate group is a rare event. The Chiapas catfish mainly feeds on crabs, prawns, small fish, and large, tough plant seeds. This catfish is commonly fished in its natural habitat, where it is known as madre de juil, which means "mother of Rhamdia" (a common fish in the area).

Comprehensive Description

    Biology
    provided by Fishbase
    Inhabits deep river channels and pools with rocks and strong eddy currents. sometimes taken in stream mouths; collected in both high and low water seasons, and generally during the night. Food include fishes, crabs, prawns, and large and tough seeds (Ref. 54757).
    Chiapas catfish
    provided by wikipedia

    The Chiapas catfish, Lacantunia enigmatica, is an unusual species of catfish (order Siluriformes) newly described in 2005 from the Lacantún River in the Mexican state of Chiapas. While discovery of an undescribed species of catfish is not uncommon, discovery of a new family-level taxon of any vertebrate group is a rare event.[1] The Chiapas catfish mainly feeds on crabs, prawns, small fish, and large, tough plant seeds.[1] This catfish is commonly fished in its natural habitat, where it is known as madre de juil, which means "mother of Rhamdia" (a common fish in the area).[1]

    Discovery

    It first came to the attention of scientists in 1996, when Rócio Rodiles-Hernández, a Mexican ichthyologist conducting a biotic survey on the river, collected the first specimens from the Chiapas-Guatemala border.[1] Unable to identify the species, Rodiles involved two American catfish specialists, Dean A. Hendrickson of the University of Texas at Austin and John G. Lundberg of the Academy of Natural Sciences of Philadelphia. A detailed comparative morphological study employing high-resolution, three-dimensional CT-scan imagery of the fish's anatomy revealed a number of distinctive characteristics unique to this species and the absence of characters needed to place this fish in any existing catfish family. In a 2005 publication, these three ichthyologists, with Julian M. Humphries of the University of Texas, described this fish as a new species, genus and family of catfish.[1]

    Taxonomy

    This fish is not related to any of the families found in its range (Ariidae, Ictaluridae, or Heptapteridae). It is most similar to Ictaluridae, but lacks some important characteristics to classify this fish into this family or the other two families. Initial study has placed this fish above Diplomystidae, Cetopsidae, and Hypsidoridae, but further classification is unknown. This family probably represents a basal group in which intermediates have disappeared.[1]

    With recent molecular evidence, Lacantunia has been shown to be the sister group to Claroteidae, an African catfish family. It probably diverged from the claroteids in the Late Cretaceous between 75 and 90 mya.[2]

    Distribution and habitat

    The generic name of the fish reflects its distribution in the Río Lacantún drainage, flowing through the Montes Azules and Selva Lacandona Biosphere Reserves in México into that country’s largest river, the Río Usumacinta. Its known distribution does not extend beyond a small area in the Lacantún and Lacanjún rivers of central Chiapas. Lacantunia has never been collected in the large Usumacinta River into which these smaller rivers flow. With the description of the new family, four catfish families are now found in this region.[1]

    These fish inhabit deep river channels and pools with rocks and strong eddy currents. Few specimens were taken in stream mouths.[1]

    Physical characteristics

    Key variations that differentiate this genus from all other families are the shape of the animal's skull, jaw muscles, and gas bladder — which fish use to rise and sink in water. The gas bladder has paired diverticulae, while other catfish families either have no diverticulae or singular diverticulae.[1] Some external characteristics that may help distinguish this fish include nostrils set far apart, the presences of nasal barbels, maxillary barbels placed above the lip distantly from the corner of the mouth, and a rounded caudal fin.[1] This fish has four pairs of barbels. The maximum length of this species reaches 42.7 centimetres (16.8 in) SL.[3] It is depressed (flattened) near the head and compressed (thin) near the tail. The head is blunt and rounded, and the mouth is usually not subterminal (down-turned). The adipose fin is large and thick. This fish has dorsal and pectoral fin spines.[1]

    References

    1. ^ a b c d e f g h i j k Rodiles-Hernández, Rocío; Hendrickson, Dean A.; Lundberg, John G.; Humphries, Julian M. (2005). "Lacantunia enigmatica (Teleostei: Siluriformes) a new and phylogenetically puzzling freshwater fish from Mesoamerica" (PDF). Zootaxa. 1000: 1–24. ISSN 1175-5334..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"""""'"'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
    2. ^ Lundberg, John G.; Sullivan, John P.; Rodiles-Hernández, Rocío; Hendrickson, Dean A. (June 2007). "Discovery of African roots for the Mesoamerican Chiapas catfish, Lacantunia enigmatica, requires an ancient intercontinental passage" (PDF). Proceedings of the Academy of Natural Sciences of Philadelphia. 156: 39–53. doi:10.1635/0097-3157(2007)156[39:DOARFT]2.0.CO;2. Archived from the original (PDF) on 2009-03-26.
    3. ^ Froese, Rainer and Pauly, Daniel, eds. (2011). "Lacantunia enigmatica" in FishBase. December 2011 version.

Morphology

    Morphology
    provided by Fishbase
    Dorsal spines (total): 2; Dorsal soft rays (total): 810; Analspines: 0

Diagnostic Description

    Diagnostic Description
    provided by Fishbase
    This species is distinguished from all other siluriforms by the following uniquely derived and anatomically complex characteristics: fifth infraorbital bone relatively wide and thick-walled, boomerang-shaped and anteriorly convex, and remote from a markedly prominent sphenotic process; the lateral margin of skull thickened along frontal bone and adjacent parts of lateral ethmoid and sphenotic bones at origins of much enlarged adductor mandibulae and levator arcus palatini muscles, otherwise the skull roof medial to muscle origins severely constricted, flat, lacking crests and fossae; a pair of cone-shaped "pseudo-pharyngobranchial" bones at anterior tips of enlarged accessory cartilages medial to first and second epibranchials; a hypertrophied, axe-shaped uncinate process on third epibranchial; gas bladder with paired spherical, unencapsulated diverticulae protruding from anterodorsal wall (Ref. 54757).

Trophic Strategy

    Trophic Strategy
    provided by Fishbase
    Inhabits deep river channels and pools with rocks and strong eddy currents. sometimes taken in stream mouths; collected in both high and low water seasons, and generally during the night. Food include fishes, crabs, prawns and large, and tough seeds.

Threats

    Threats
    provided by Fishbase
    Not Evaluated