Trichomycterus

Taxobox
name = "Trichomycterus"


image_width = 240px
regnum = Animalia
phylum = Chordata
classis = Actinopterygii
ordo = Siluriformes
familia = Trichomycteridae
subfamilia = Trichomycterinae
genus = "Trichomycterus"
genus_authority = Valenciennes, 1832
type_species = "Trichomycterus nigricans"
type_species_authority = Valenciennes, 1832
subdivision_ranks = Species
subdivision ="See text."

"Trichomycterus" is a genus of catfishes, the largest genus in the family Trichomycteridae with over 100 species currently described.

Taxonomy

This genus is defined by the lack of specializations found in other trichomycterids and is certainly polyphyletic. Although known to contain many species, "Trichomycterus" is poorly known with many of the known species based on brief descriptions. Many species have been described recently and many more are waiting to be described.

Some authors have tentatively defined putative monophyletic assemblages within the genus "Trichomycterus" based on the possession of unique morphological features. The "T. brasiliensis" species-complex includes "T. brasiliensis", "T. iheringi", "T. maracaya", "T. mimonha", "T. potschi", "T. vermiculatus", and several undescribed species apparently endemic to the main river basins draining the Brazilian Shield. However, an assemblage of species from south and southeastern Brazil is also supported that includes "T. guaraquessaba", "T. iheringi", "T. nigricans", "T. davisi", "T. stawiarski", "T. castroi", "T. triguttatus", "T. immaculatus", "T. itatiayae", "T. mirissumba", "T. zonatus", "T. naipi", "T. taboba", "T. papilliferus", "T. mboycy", and "T. plumbeus". "T. aguarague", "T. alterus", "T. boylei", "T. ramosus", and "T. belensis" also form a diagnosable species assemblage.

Distribution and habitat

Species of "Trichomycterus" inhabit a diversity of habitats throughout South and Central America from Costa Rica in the north to Patagonia in the south, and from lowland Atlantic rainforest in the east to Andean streams in the west. A number of species of "Trichomycterus" are known from various mid- to high-elevation localities in western Argentina; in these upland regions the species of "Trichomycterus" are among the few, or sometimes only, fishes occupying water bodies at middle to higher elevations. About 60 nominal species are endemic to the river basins draining the Andes and hills of the Guianan Shield, and about 30 species are endemic to river basins draining the Brazilian Shield.

Despite the broad distribution of the genus, most species have limited distributions, and usually are restricted to only one river. Wide-ranging species are most likely complexes of species that are difficult to differentiate, such as the "T. brasiliensis" species-complex. "Trichomycterus gorgona", from a small stream on Gorgona Island located west of the Pacific coast of Colombia, is the first known trichomycterid to be endemic to an offshore island.

Six hypogean species are in the genus "Trichomycterus": "Trichomycterus chaberti", "T. itacarambiensis", "T. santanderensis", "T. spelaeus", and "T. uisae".cite journal|title="Trichomycterus uisae": a new species of hypogean catfish (Siluriformes: Trichomycteridae) from the northeastern Andean Cordillera of Colombia|first=Cesar A.|last=Castellanos-Morales|journal=Neotropical Ichthyology|volume=6|issue=3|pages=307-314|year=2008]

Description

These fish are generally small, usually about 50–150 millimetres (2.0–5.9 in) SL. Species differ from one another primarily in body proportions, fin ray counts, and colouration.

pecies

Species list according to Ferraris, 2007; newer species with references.cite journal|url=http://silurus.acnatsci.org/ACSI/library/biblios/2007_Ferraris_Catfish_Checklist.pdf|title=Checklist of catfishes, recent and fossil (Osteichthyes: Siluriformes), and catalogue of siluriform primary types|first=Carl J., Jr.|last=Ferraris|journal=Zootaxa|volume=1418|pages=1–628|year=2007|format=PDF]

References