Picture by Chad Thomas, Texas State University-San Marcos



Etheostoma chlorosoma

bluntnose darter



Type Locality

Branch of Tuscumbia River, at Corinth, Alcorn County, Mississippi; Sand Creek, near Artesia, Lowndes County, Mississippi; and Horsehunter Creek, at Macon, Noxubee County, Mississippi (Hay 1881).


Etymology/Derivation of Scientific Name

Etheostoma, from the Greek etheo, “to strain,” and stoma, “mouth;” chlorosoma, Greek, meaning “greenish-yellow” (Pflieger 1997).



Vaillantia chlorosoma Hay 1881:495.

Vaillantia camura Hay 1883:62.

Beleosoma camurum Hildebrand and Towers 1928:125.

Etheosoma chlorosomum Cook 1959:201.



Maximum size: 50 mm SL (Etnier and Starnes 1993; Carlander 1997).


Coloration: Head with preorbital bars that extend (and connect) around snout in addition to dark suborbital bars and postorbital spots; lateral region greenish-yellow with dark "X" and "M" shaped markings and a small dark caudal spot; ventral region white.  Dorsal and caudal fins with light brown stripes; other fins are colorless.  Breeding males have the above colors in a darker shade with operculum having a metallic green coloration and the first dorsal fin with black stripes notable anteriorly.


Counts: Data for specimens collected in the Colorado, Brazos, San Jacinto, Trinity, Neches, and Sabine drainages: 52-63 total lateral line scales, 10-40 are pored; 11-15 scales in transverse series; 16-23 caudal peduncle scale rows. Fin rays: dorsal 8-12; anal 7-10; branched caudal 12-15; total pectoral 24-28; pelvic 5 (Bart and Cashner 1986). 1 anal fin spine (Hubbs et al. 1991).


Body shape: Elongated and slender. 


Mouth position: Subterminal and horizontal.


External morphology:  Incomplete lateral line, blunt snout. Bart and Cashner (1986) noted sexual dimorphism in the following characters: Breeding males with small, tubular shaped genital papillae and thickened, fleshy pelvic and anal spines; tubercles observed on pelvic and anal spines; tubercles usually present on the anterior rays of these fins, but sometimes seen on all rays and spines. Females with large, fleshy heart-shaped genital papillae which increased in size as females approached height of breeding condition. Mature males and females have two rows of tubercle-like structures on the interradial membrane of the caudal fin (distribution and fleshy nature of structures suggests function similar to contact organs during spawning; Bart and Cashner 1986).


Distribution (Native and Introduced)

U.S. distribution: Mississippi River drainage and gulf slope drainages from Alabama to Texas (Hubbs et al. 1991).


Texas distribution: Guadalupe River drainage eastward (Hubbs et al. 1991). Warren et al. (2000) listed the following drainage units for distribution of Etheostoma chlorosomum in the state: Red River (from the mouth upstream to and including the Kiamichi River), Sabine Lake (including minor coastal drainages west to Galveston Bay), Galveston Bay (including minor coastal drainages west to mouth of Brazos River), Brazos River, Colorado River, San Antonio Bay (including minor coastal drainages west of mouth of Colorado River to mouth of Nueces River).


Abundance/Conservation status (Federal, State, NGO)

Currently secure (Warren et al. 2000).


Habitat Associations

Macrohabitat: Low gradient, clear, small streams to moderate-sized rivers (Gilbert 1980; Simon and Wallus 2006). Specimens collected from middle Brazos River (Texas) oxbow lakes (Winemiller et al. 2000; Zeug et al. 2005).


Mesohabitat: Backwaters, pools, and areas of slow current in areas with organic debris, silt, and sand (Gilbert 1980; Bart and Cashner 1986; Simon and Wallus 2006). Abundance of this species apparently unaffected by removal of submersed aquatic vegetation in Lake Conroe, a reservoir in the headwaters of the San Jacinto River, southeastern Texas, as it was rare when vegetation was abundant, and did not increase in abundance following vegetation removal (Bettoli et al. 1993).



Spawning season: Early January to late March, in east Texas (Hubbs 1985). Spawning temperatures range from 22-26°C (Simon 1994).


Spawning location: Nest spawners on plants or plant debris (Winn 1958; Carlander 1997).  Female selects spawning site; eggs laid on algae, twigs, and leaves (Page et al. 1982).


Reproductive strategy: Guarders; substratum spawners; phytophils – have adhesive eggs that are attached to a variety of plants. Free embryos without cement glands (Page et al. 1982; Bart, unpublished data in: Simon 1999). Male swims near female, both vibrate while depositing milt and one to three eggs per bout (Page et al. 1982).


Fecundity: Females measuring 38-49 mm TL collected from a creek in Union Parish, Louisiana, had a mean ovary weight that was 17.1% of the body weight, containing a mean of 117.6 total ova that average 0.83 mm in diameter; females showed statistically significant increasing fecundity with increasing length; females 38-49 mm TL had 73-171 large mature ova (Simon, T.P., unpublished data; Simon and Wallus 2006). Eggs from Louisiana are spherical, range from 0.9-1.1 mm diameter (mean 1.0 mm), translucent, demersal, and nonadhesive (Simon 1994). Eggs from Cummins Creek and various Neches River tributaries, Texas, average 1.05 mm in diameter; hatching occurs after 156-211 hours at an incubation temperature of 26°C (Hubbs 1967).


Age/size at maturation: No information; likely before age-1. Simon and Wallus (2006) reported that female specimens from an unnamed creek in Union Parish, Louisiana were sexually mature at 39 mm TL.


Migration: NA


Longevity: Up to three years (Etnier and Starnes 1993).


Food habits: Benthic invertivore (Goldstein and Simon 1999). In Tennessee specimens, stomachs contained hydropsychid caddisfly, dytiscid beetle, and midge larvae (Etnier and Starnes 1993; Goldstein and Simon 1999).


Growth: Larval size range 5.6-14.0 mm TL (Simon 1994; Simon and Wallus 2006). Etnier and Starnes (1993) reported that young-of-year were about 30 mm TL in mid-August; based on length classes and scale annuli, other age groups in a large August collection were 37-41 mm, and 46-50 mm TL.


Phylogeny and morphologically similar fishes

Subgenus Vaillantia (Gilbert 1980). 


Commercial or Environmental Importance

      [Additional literature noting collection of this species from Texas locations includes, but is not limited to the following: Hubbs and Hettler (1958); Evans and Noble (1979); Kleinsasser and Linam (1987); Linam and Kleinsasser (1987); Winemiller (1991); Matthews et al. (1996); Moriarty and Winemiller (1997); Winemiller et al. (2004).]


Host Records

Urocleidus chlorosomus and U. lottensis (Trematoda: Monogenea), reported from species in southern Mississippi

(Harrises and Vickery 1970).



Bart, H.L., Jr. and R.C. Cashner. 1986. Geographic variation in Gulf slope populations of the bluntnose darter, Etheostoma chlorosomum (Hay) Tulane Stud. Zool. Bot. 25(2):151-170.

Bettoli, P.W, M.J. Maceina, R.L. Noble, and R.K. Betsill. 1993. Response of a reservoir fish community to aquatic vegetation removal. North American Journal of Fisheries Management 13:110-124.

Carlander, K.D. 1997. Handbook of Freshwater Fishery Biology. Vol. 2. Iowa State Univ. Press, Ames. 397 pp.

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

Etnier, D.A., and W.C. Starnes. 1993. The Fishes of Tennessee. University of Tennessee Press, Knoxville. 681 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.

Gilbert, C.R. 1980. Etheostoma chlorosomum (Hay), Bluntnose darter. pp. 634 in D. S. Lee, et al. Atlas of North American Freshwater Fishes. N. C. State Mus. Nat. Hist., Raleigh, i-r+854 pp.

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. 671 pp.

Harrises, A.E., and R.L. Vickery. 1970. Additional species of Ancyrocephalinae (Trematoda: Monogenea) from darters of southern Mississippi. American Midland Naturalist 84(2):437-443.

Hay, O.P. 1881. On a collection of fishes from eastern Mississippi. Proc. U.S. Nat. Mus. 3:488-515.

Hay, O.P. 1883. On a collection of fishes from lower Mississippi valley. Proc. Bull. U.S. Fish Comm. 2:57-75.

Hildebrand S.F. and I.L. Towers. 1928. Annotated list of fishes collected in the vicinity of Greenwood, Mississippi, with descriptions of three new species. Bull. U.S. Bur. Fish. 43(2):105-136.

Hubbs, C. 1967. Geographic variations in survival of hybrids between etheostomine fishes. Bull. Texas. Mem. Mus. No. 13. 72 pp.

Hubbs, C. 1985. Darter reproductive seasons. Copeia 1985(1):56-68.

Hubbs, C., and W.F. Hettler. 1958. Fluctuations of some Central Texas fish populations. The Southwestern Naturalist 3(1/4):13-16.

Kleinsasser, L.J., and G.W. Linam. 1987. Fisheries use attainability study for Pine Island Bayou (Segment 0607). River studies Report No. 6. Resource Protection Division. Texas Parks and Wildlife, Austin. 19 pp.

Linam, G.W., and L.J. Kleinsasser. 1987. Fisheries use attainability study for Cow Bayou (Segment 0511). River Studies Report No. 5. Resource Protection Division. Texas Parks and Wildlife Department, Austin. 14 pp.

Matthews, W.J., M.S. Schorrs, and M.R. Meador. 1996. Effects of experimentally enhanced flows on fishes of a small Texas (U.S.A.) stream: assessing the impact of interbasin transfer. Freshwater Biology 35:349-362.

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 49(3):85-110.

Page, L.M., M.E. Retser, and R.A. Stiles. 1982. Spawning behavior in seven species of darters (Pisces: Percidae). Brimleyana. 8:135-143.

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

Simon, T.P. 1994. Ontogeny and systematics of darters (Percidae) with discussion of ecological effects of larval morphology. Doctor of Philosophy Thesis, University of Illinois, Chicago. 672 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.

Simon, T.P., and R.Wallus. 2006. Reproductive Biology and Early Life History of Fishes in the Ohio River Drainage, Volume 4. Taylor and Francis Group, Boca Raton, Florida. 619 pp.

Warren, M.L.., 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.

Winemiller, K.O. 1991. Ecomorphological diversification in lowland freshwater fish assemblage from five biotic regions. Ecological Monographs 61(4):343-365.


Winemiller, K.O., F.P. Gelwick, T.H. Bonner, S. Zeug, and C. Williams. 2004. Response of oxbow lake biota to hydrologic exchanges with the Brazos River channel. Final Project Report to the Texas Water Development Board. 59 pp.


Winemiller, K.O., S. Tarim, D. Shormann, and J.B. Cotner. 2000. Fish assemblage structure in relation to environmental variation among Brazos River oxbow lakes. Trans. Amer. Fish. Soc. 129:451-468.

Winn, H.E. 1958. Comparative reproductive behavior and ecology of fourteen species of darters (Pisces, Percidae). Ecological Monographs 28(2):155-191.

Zeug, S.C., K.O. Winemiller, and S. Tarim. 2005. Response of Brazos River assemblage to patterns of hydrologic connectivity and environmental variability. Trans. Amer. Fish. Soc. 134:1389-1399.