Madtoms are freshwater
catfishes (
order Siluriformes) of the
genusNoturus of the
familyIctaluridae. It is the most species-rich family of catfish in North America, native to the central and eastern United States, and adjacent parts of Canada.[1] Their fin spines contain a mild venom with a sting comparable to that of a
honey bee.[2]
Nearly half the species of madtom catfishes were described in a single comprehensive revision of the group.
Morphology is very conserved in this genus; most of the species look very similar and telling them apart with the usual
meristic and
morphometric characters used to identify species is difficult. The more conspicuously variable attributes of these secretive fishes are features of pigmentation, which also are more difficult to quantify and often vary according to
substrate and water quality.[1] These species have small to tiny or fragmented
ranges, and aspects of
pigmentation are important diagnostic characters of each.[1] Over one-quarter of the recognized species diversity in Noturus remains undescribed.[3]
A number of madtom species are narrowly distributed and extremely rare, and thus are at great risk of
extinction. Noturus trautmani was last sighted in 1957 and declared extinct in 2023.[1][4]
^
abcdBurr, Brooks M.; Eisenhour, David J.; Grady, James M. (2005). Armbruster, J. W. (ed.). "Two New Species of Noturus (Siluriformes: Ictaluridae) from the Tennessee River Drainage: Description, Distribution, and Conservation Status". Copeia. 2005 (4): 783–802.
doi:
10.1643/0045-8511(2005)005[0783:TNSONS]2.0.CO;2.
^Florida Museum of Natural History: Ictaluridae Retrieved 6 April 2014.