Picture by Chad Thomas, Texas State University-San Marcos



Noturus nocturnus

freckled madtom



Type Locality

Saline River near Benton railroad bridge, AR (Jordan and Gilbert 1886).


Etymology/Derivation of Scientific Name

Noturus, Greek, meaning “black tail,” in reference to the connection of the adipose fin and tail fin; nocturnus, Latin for “nocturnal” from its black color (Pflieger 1997).



Noturus nocturnus Jordan and Gilbert 1886:6; Cook 1959:142.



Maximum size: 138 mm SL (Ross 2001).


Coloration: Axial streak inconspicuous; dorsal, anal and caudal fins with dark edges; lower lip and chin heavily speckled with dark pigment (Hubbs et al.1991). The back and sides are uniformly yellowish to dark brown (dark gray in preservation), and the ventral surface is generally unpigmented, with scattered melanophores on the lower jaw and sides of the belly. The nasal and maxillary barbles are dark. The pelvic and pectoral fins are only pigmented along the basal half in small specimens (Ross 2001).


Counts: 5-6 gillrakers, 6-7 dorsal rays, 16-18 (15-20) anal rays, 8-10 (7-11 pectoral rays, and 9 (8-10) pelvic rays (Ross 2001).


Body shape: Moderately elongate. Posterior corners of premaxillary tooth patch  rounded or obtusely angulate (Boschung and Mayden 2004). Lower jaw underslung (Hubbs et al. 1991).


Mouth position: Subterminal (Hubbs et al.1991).


External morphology: Pectoral spine serrated; adipose fin joined to caudal fin or separated from it by not more then a shallow notch; eyes present (Hubbs et al.1991).


Distribution (Native and Introduced)

U.S. distribution: Lower and central Mississippi basin and other Gulf of Mexico tributaries in Alabama, Mississippi, Louisiana, Texas, as well as lower half of Ohio basin in KY, IN, and IL (Rhode 1980).


Texas distribution: Found primarily in eastern Texas from Red River southward to Brazos Basin (Hubbs et al. 1991).


Abundance/Conservation status (Federal, State, NGO):

Not listed as threatened or endangered by Texas Parks and Wildlife Department (2006). Populations in southern United States are currently stable (Warren et al. 2000).


Habitat Associations

Macrohabitat: Inhabits clear to moderately turbid streams of medium to larges size having permanent flow and low to moderate gradients (Rhode 1980).


Mesohabitat: In riffles over gravelly or rocky bottom (Rhode 1980; Burgess 2003). In southern Mississippi, it also occurs in association with sticks, root masses, and submerged logs, especially along undercut banks. Young individuals will shelter in beverage cans and soft-drink and beer bottles, but adults are generally too large to fit through openings (Clark 1978). In Illinois, breeding males were found in beverage cans (Burr and Mayden 1982). N. nocturnus is an intolerant species sensitive to environmental conditions and typically first to disappear following a disturbance; fluvial specialist having narrow range of habitat use. Associated more with unchannelized reaches of the South Sulpher River, Texas, and generally occupying riffle habitat. (Burgess 2003). In South Sulpher River, Texas, species associated with higher velocities and with riffle-habitat types and shallower depths that occurred during the low flow range (Morgan 2002).



Spawning season: In southeast Missouri, females with fully developed eggs were collected in late May, suggesting a spring-early summer spawning season (Pflieger 1975). In summer, in southern Mississippi (Clark 1978), and from May-July in Illinois.


Spawning habitat: Speleophils (hole nesters; Simon 1999); nests located in areas with some current, in water 10-15cm deep (Burr and Mayden 1982).


Reproductive strategy: Guarders; nest spawners (Mayden and Walsh 1984; Simon 1999).


Fecundity: Mature ova range from 1.8 to2.3mm in diameter and number from 85-116 in females of 67 -75 mm SL (Burr and Mayden 1982).


Age at maturation: Males reach maturity by third summer and females by their second (Burr and Mayden 1982).




Growth and population structure: Growth initially rapid, reaching half of first year’s growth in only eight weeks. At one year fish average 64-66 mm SL, and average 77-79 mm SL and 84-86 mm SL by their second and third years respectively (Burr and Mayden 1982).


Longevity: 4.5 years (Burr and Mayden 1982).


Food habits: Invertivore; benthic; lie-in-wait/ambush feeding behavior (Goldstein and Simon 1999). Aquatic insect larvae, especially larvae of mayflies (Ephemeroptera), caddisflies (Trichoptera), and midges (Diptera). Black fly larvae are more prevalent in the fall (Burr and Mayden 1982). In southern Mississippi, smaller Noturus leptacanthus were consumed, indicating piscivory occasionally occurs. As with other madtoms feeding activity is greatest at night (Clark 1978). Nesting males apparently do not feed (Burr and Mayden 1982).


Phylogeny and morphologically similar fishes

It can be distinguished from the Noturus gyrinus by having an inferior (versus terminal) mouth (Ross 2001). N. gyrinus, found in Texas, is among the species to which N. nocturus is most closely related (Grady and LeGrande 1992).


Host Records



Commercial or Environmental Importance


[Additional literature noting collection of this species from Texas locations includes, but is not limited to the following: Big Sandy Creek (Evans and Noble 1979); Village Creek (Moriarty and Winemiller 1997); El-Hage et al. (1999).]



Burgess, C.C. 2003. Summer fish assemblages in channelized and unchannelized reached of the South Sulpher River, Texas. M.S. Thesis. Texas A&M University, College Station, Texas. 94 pp.

Boschung, H.T., Jr., and R.L. Mayden. 2004. Fishes of Alabama. Smithsonian Books, Washington. 736 pp.

Burr, B.M. and R.L. Mayden. 1982. Life history of the freckled madtom, Noturus nocturnus, in Mill Creek, Illinois (Pisces: Ictaluridae). Occ. Pap. Mus. Nat. Hist. Univ. Kans. 98:1-15.

Clark, K.E. 1978. Ecology and life history of the speckled madtom, Noturus leptacanthus (Ictaluridae). Master’s thesis, Univ. S. Mississippi, Hattiesburg.

Cook, F.A. 1959. Freshwater fishes in Mississippi. Mississippi Game and Fish Commision, Jackson. 239 pp.

El-Hage, A., D.W. Moulton, P.D. Sorenson. 1999. Evaluation of Selected Natural Resources in Part of the North-Central Texas Area. Resource Protection Division. Texas Parks and Wildlife, Austin. 36 pp.

Evans, J.W., and R.L. Noble. 1979. Longitudinal distribution of fishes in an East Texas stream. American Midland Naturalist 101(2):333-343.

Goldstein, R.M., and T.P. Simon. 1999. Toward a united definition of guild structure for feeding ecology of North American freshwater fishes. pp. 123-202 in T.P. Simon, editor. Assessing the sustainability and biological integrity of water resources using fish communities. CRC Press, Boca Raton, Florida.

Grady, J.M. and W.H. LeGrande. 1992. Phylogenetic relationships, modes of speciation, and historical biogeography of the madtom catfishes, genus Noturus Rafinesque (Siluriformes: Ictaluridae). pp. 747-777. In: Systematics, historical ecology, and North American freshwater fishes. R.L. Mayden ed. Stanford Univ. Press, Stanford, Calif.

Hubbs, C., R.J. Edwards and G.P. Garret. 1991. An annotated checklist of freshwater fishes of Texas, with key to identification of species. Texas Journal of Science, Supplement 43(4):1-56

Jordan, D.S. and C.R. Gilbert. 1886. List of fishes collected in Arkansas Indian territory, and Texas, in September, 1884, with notes and descriptions. Proc. US. Nat. Mus. 9(15):1-25.

Mayden, R.L., and S.J. Walsh. 1984. Life history of the least madtom Noturus hildebrandi (Siluriformes: Ictaluridae) with comparisons to related species. American Midland Naturalist 112:349-368.

Morgan, M.N. 2002. Habitat associations of fish assemblages in the Sulpher River, Texas. Master’s thesis. Texas A&M University, College Station, TX. 58 pp.

Moriarty, L.J., and K.O. Winemiller. 1997. Spatial and temporal variation in fish assemblage structure in Village Creek, Hardin County, Texas. Texas Journal of Science, Supplement 49(3):85-110.

Pflieger, W.L. 1997. The Fishes of Missouri. Revised Edition. Missouri Department of Conservation. Jefferson City. 372 pp.

Ross, S. T. 2001. The Inland Fishes of Mississippi. University Press of Mississippi, Jackson. 624 pp.

Rhode, F.C. 1980. Noturus nocturnus (Jordan and Gilbert), Freckled madtom. pp.466 in D.S. Lee et al. Atlas of North American Freshwater Fishes. N.C. State Mus. Nat. Hist., Raleigh, i-r+854 pp.

Simon, T. P. 1999. Assessment of Balon’s reproductive guilds with application to Midwestern North American Freshwater Fishes, pp. 97-121. In: Simon, T.L. (ed.). Assessing the sustainability and biological integrity of water resources using fish communities. CRC Press. Boca Raton, Florida. 671 pp.

Texas Parks and Wildlife Department, Wildlife Division, Diversity and Habitat Assessment Programs. County Lists of Texas' Special Species. [30 May 2006]. http://gis.tpwd.state.tx.us/TpwEndangeredSpecies/DesktopModules/AcountyCodeKeyForWebESDatabases.pdf

Warren, L. W., Jr., B. M. Burr, S. J. Walsh, H. L. Bart, Jr., R. C. Cashner, D. A. Etnier, B. J. Freeman, B. R. Kuhajda, R. L. Mayden, H. W. Robison, S. T. Ross, and W. C. Starnes. 2000. Diversity, Distribution, and Conservation status of the native freshwater fishes of the southern United States. Fisheries 25(10):7-29.