The Ozark madtom (''Noturus albater'') is a
freshwater fish
Freshwater fish are fish species that spend some or all of their lives in bodies of fresh water such as rivers, lakes, ponds and inland wetlands, where the salinity is less than 1.05%. These environments differ from marine habitats in many wa ...
endemic
Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...
to the United States. It is one of 29 species of
madtom
Madtoms are freshwater catfishes (order (biology), order Siluriformes) of the genus ''Noturus'' of the family (biology), family Ictaluridae. It is the most species-rich genus of catfish in North America, native to the central and eastern United S ...
.
Description
The Ozark madtom has a stout body and small head. A dark bar can be found at the base of the caudal fin, and the caudal fin is usually straight or slightly rounded. The pectoral fin has 9 rays, and the anal fin has 13 to 16 rays. The fish has a total length of 120 mm (4 in).
Distribution and habitat
The Ozark madtom are found around the upper
White River and the
Little Red River in the
Ozark Uplands in
Arkansas
Arkansas ( ) is a landlocked state in the West South Central region of the Southern United States. It borders Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, Texas to the southwest, and Oklahoma ...
and
Missouri
Missouri (''see #Etymology and pronunciation, pronunciation'') is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. Ranking List of U.S. states and territories by area, 21st in land area, it border ...
, United States.
The Ozark madtom can by found in
riffle
A riffle is a shallow landform in a flowing channel. Colloquially, it is a shallow place in a river where water flows quickly past rocks. However, in geology a riffle has specific characteristics.
Topographic, sedimentary and hydraulic indica ...
s and rocky pools, as well as cool, clear, high-gradient creeks and small to medium-sized rivers. They are found in shallow depths (usually of less than half a meter deep) and high velocity currents.
During the day, they use the rocky bed bottom as cover.
Diet
Most of the Ozark madtom's diet consists of aquatic insects, with
Diptera
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 advance ...
(flies) making up a majority.
Ephemeroptera (mayflies) make up most of the remainder of the diet.
[
]
Behavior
It is presumed that Ozark madtom are nocturnal
Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite.
Nocturnal creatur ...
.[
Nests are found under small flat rocks in pools that are about one-third to two-thirds of a meter deep.][
]
Life history
Ozark madtoms have yellow spherical eggs. Their eggs adhere to each other but to no other surfaces. After about 4 days after spawning, the embryos obviously show blood, myomere
Myomeres are blocks of skeletal muscle tissue arranged in sequence, commonly found in aquatic chordates. Myomeres are separated from adjacent myomeres by fascia consisting of connective tissue, known as myosepta. Myomere counts are sometimes us ...
s are well developed, the tail is free from the yolk sac
The yolk sac is a membranous wikt:sac, sac attached to an embryo, formed by cells of the hypoblast layer of the bilaminar embryonic disc. This is alternatively called the umbilical vesicle by the Terminologia Embryologica (TE), though ''yolk sac' ...
, pigment is well developed in the eye, and a couple sets of barbels
In fish anatomy and turtle anatomy, a barbel is a slender, whisker like sensory organ near the mouth (sometimes called whiskers or tendrils). Fish that have barbels include the catfish, the carp, the goatfish, the hagfish, the sturgeon, the z ...
are beginning to form.
At hatching, the larvae are 8 mm (0.3 in) long and mostly translucent. They gain melanophores
Chromatophores are cells that produce color, of which many types are pigment-containing cells, or groups of cells, found in a wide range of animals including amphibians, fish, reptiles, crustaceans and cephalopods. Mammals and birds, in contrast ...
on their head. Caudal and anal fins begin to develop and another pair of barbels appears near the nostrils. About 7 days after hatching, the larvae are 12 mm (0.5 in) long. All fins are nearly adult-like. The barred pattern found in adults does not form until later.
After 9 months, the fish are about 53 mm (2 in) long.[
]
Predators
'' Luxilus zonatus'' (bleeding shiners) are known to prey upon the Ozark madtom's eggs, while ''Etheostoma caeruleum
The rainbow darter (''Etheostoma caeruleum'') is a small species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is native to No ...
'' (rainbow darters) and ''Percina evides
The gilt darter (''Percina evides'') is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It can be found in a number of st ...
'' (gilt darters) are known to prey upon the Ozark madtom's larvae.[
]
Parasites
Ozark madtoms are known to possess ''Lernaea
''Lernaea'' is a genus of copepod crustaceans whose members are commonly called ''anchor worms'' and are parasitic on fresh water, freshwater fishes.
Life cycle
Anchor worms mate during the last free-swimming (copepodid) stage of development. A ...
'' scars.[
]
References
{{Taxonbar , from=Q2889495
Noturus
Fish described in 1969
Freshwater fish of the United States
Endemic fish of the United States