The Ouachita madtom (''Noturus lachneri'') is a catfish of the family Ictaluridae. The first specimens of the species were collected in 1952 it was not until 1969 that they were recognised as a species. The Ouachita madtom is similar to the tadpole madtom (''N. gyrinus'') except the Ouachita madtom has one internasal pore while the tadpole madtom has two, and 16 to 18 anal rays while the tadpole madtom has only 14 to 16. It is also similar to the

slender madtom ''Noturus exilis'', also called the slender madtom, is a species of the catfish family Ictaluridae. Ictaluridae includes bullheads, madtoms, channel catfish, and blue catfish. ''Noturus exilis'' is found in the central portion of the Mississipp ...

(''N. exilis'') but differing in the lack of serrae on the pectoral

spine Spine or spinal may refer to: Science Biology * Vertebral column, also known as the backbone * Dendritic spine, a small membranous protrusion from a neuron's dendrite * Thorns, spines, and prickles, needle-like structures in plants * Spine (zoolog ...

, having more caudal rays, and usually eight pectoral rays while the slender madtom has 9. The maximum length of an Ouachita madtom is about .

Distribution

The Ouachita madtom was considered an

Endangered Species An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inv ...

by the

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

in 1986 and 1988. Assessments in 1990 and 1994 showed it to be

vulnerable Vulnerable may refer to: General * Vulnerability * Vulnerability (computing) * Vulnerable adult * Vulnerable species Music Albums * ''Vulnerable'' (Marvin Gaye album), 1997 * ''Vulnerable'' (Tricky album), 2003 * ''Vulnerable'' (The Used album) ...

, but it was again listed as endangered in 2010. The Ouachita madtom is found only in the upper forks of the Saline River (Ouachita River) system and in one tributary of the Ouachita River in Central Arkansas, United States.

Habitat

A usual inhabitant of clear, small to medium,

gravel Gravel is a loose aggregation of rock fragments. Gravel occurs naturally throughout the world as a result of sedimentary and erosive geologic processes; it is also produced in large quantities commercially as crushed stone. Gravel is classifi ...

-bottomed

streams A stream is a continuous body of water, body of surface water Current (stream), flowing within the stream bed, bed and bank (geography), banks of a channel (geography), channel. Depending on its location or certain characteristics, a stream ...

, the Ouachita madtom has been found in extremely shallow areas of the Saline River. It also is found in quiet

backwater Backwater or Backwaters may refer to: Music * ''Backwaters'' (album), a 1982 album by American guitarist Tony Rice * Backwater (band), a jazz fusion band from Mobile, Alabama, or this band's 1976 debut album * "Backwater", a song by Brian Eno fro ...

s under large rocks.

Reproduction

Little is known about the Ouachita madtom's

reproduction Reproduction (or procreation or breeding) is the biological process by which new individual organisms – "offspring" – are produced from their "parent" or parents. Reproduction is a fundamental feature of all known life; each individual or ...

. However, on August 1, 1980 six Ouachita madtoms were collected in a stream only across. The six specimens were obviously young-of-the-year and their presence raised speculations that Ouachita madtoms seek smaller streams during summer months to spawn.

Known food sources

The Ouachia madtom starts feeding around 20 to 90 minutes after sunset. The following are known sources of food: * Ephemeropterans *

Dipterans Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...

* Coleopterans * Trichopterans * Isopods *

Copepods Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat. Some species are planktonic (inhabiting sea waters), some are benthic (living on the ocean floor), a number of species have p ...

* Gastropods

Environmental threats

* Impoundment of water supply * Commercial gravel operations * Channelization * Clear cutting

Conservation

The Ouachita madtom is considered a species of greatest conservation need by the Arkansas Game and Fish Commission. The penalties for any form of trafficking or taking of Ouachita madtoms can be as serious as a $500,000 USD fine, 1 year imprisonment, or both. In addition to the penalties listed, civil penalties may be up to US$25,000 in fines.

References

* Fishes of Arkansas, Robinson, Henry W., Thomas M. Buchanan, University of Arkansas Press, Fayetteville, 1984, pp. 307–308. *Distribution, Habitat and Food of the Quachita Madtom, Noturus lachneri, an Ouachita River Drainage Endemic *Henry W. Robison, George L. Harp. Copeia, Vol. 1985, No. 1 (Feb. 11, 1985), pp. 216–220 * United States Fish and Wildlife Service Threatened and Endangered Species System {{Taxonbar, from=Q3756711 Noturus Freshwater fish of the United States Fish of the Eastern United States Endemic fish of the United States Endemic fauna of Arkansas Fish described in 1969 Ouachita River