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Pearl River, at Jackson, Hinds, and Rankin counties, Mississippi (Jordan 1885).
Etymology/Derivation of Scientific Name
Hybognathus hayi Jordan 1885:548.
Hybognathus argyritis Hay
Maximum size: 12 cm TL (Page and Burr 1991).
Coloration: Mid-dorsal with a thin stripe flanked on each side by another faint dark stripe; no black band through eye to snout (Hubbs et al. 2008). Peritoneum black (Goldstein and Simon 1999).
Counts: Fewer than 45 lateral line scales; pharyngeal teeth in main row typically 4-4; fewer than 10 soft rays on dorsal fin (Hubbs et al. 2008). Pharyngeal teeth 0,4-4,0 (Page and Burr 1991).
Mouth position: Terminal (Goldstein and Simon 1999).
Body shape: Eye shorter than snout; distance from anal fin origin to end of caudal peduncle goes 2.5 or fewer times in distance from tip of snout to anal fin origin (Hubbs et al. 2008).
External morphology: Predorsal scales not crowded except for fish with 9 or more anal fin rays; first obvious dorsal fin ray a thin splint, closely attached to the following well developed but unbranched ray, especially at tip; lower lip thin, without a fleshy lobe; lateral line usually not decurved, either straight or with a broad arch; premaxillaries protractile; upper lip separated from skin of snout by a deep groove continuous across the midline; cartilaginous ridge of lower jaw hardly evident and not separated by a definite groove from the lower lip (Hubbs et al. 2008).
Internal morphology: Intestinal canal long, more than twice standard length (Hubbs et al. 2008).
Distribution (Native and Introduced)
U.S. distribution: Lowland streams of the southern Mississippi and adjacent basins from Illinois and Indiana southward (Hubbs et al. 2008).
Texas distribution: Restricted to the Sabine and Cypress basins (Hubbs et al. 2008).
Abundance/Conservation status (Federal, State, NGO)
Currently Stable (Warren et al. 2000) in the southern United States. Gilbert (1980) noted that this species was sometimes common in preferred habitat, but apparently extirpated from some areas in northern parts of range (e.g. southeastern Missouri).
Mesohabitat: Lowland species inhabiting sluggish pools and backwaters of low-gradient streams (Gilbert 1980).
Age at maturation:
Growth and Population structure:
Food habits: Detritivore (Goldstein and Simon 1999).
Phylogeny and morphologically similar fishes
Hybognathus hayi is similar in appearance to the Mississippi silvery minnow (H. nuchalis), a species with which it frequently occurs (Gilbert 1980).
Commercial or Environmental Importance
Fingerman, S.W., and R.D. Suttkus. 1961. Comparison of Hybognathus hayi Jordan and Hybognathus nuchalis Agassiz. Copeia 1961(4):462-467.
Gilbert, C.R. 1980. Hybognathus hayi (Jordan)), Cypress minnow. pp. 176 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.
Hubbs, C., R.J. Edwards, and G.P. Garrett. 2008. An annotated checklist of the freshwater fishes of Texas, with keys to identification of species. Texas Journal of Science, Supplement, 2nd edition 43(4):1-87.
Jordan, D.S. 1885. Description of a new species of Hybognathus (Hybognathus hayi) from Mississippi. Proc. U.S. Natl. Mus.  7(31):548-550.
Page, L. M. & B. M. Burr. 1991. A field guide to freshwater fishes of North America north of Mexico. Houghton Mifflin Company, Boston, Massachusetts. 432 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.