scaly sand darter
Pearl River, Jackson, MS (Hay 1881).
Etymology/Derivation of Scientific Name
Ammocrypta, Greek, meaning “sand concealed,” in reference to the habit of lying buried in the sand; vivax, Latin meaning “lively, vivacious” (Pflieger 1975).
Ammocrypta vivax Hay 1883:58 (type locale: Pearl River at Jackson, Mississippi). F.A. Cook 1959:209.
Maximum size: 72 mm SL (Etnier and Starnes 1993).
Coloration: Lateral blotches longer than deep (Hubbs et al. 1991). Compared to other species of Ammocrypta, the body is less translucent in life and has light yellow tinge. The back has irregular dark blotches, often with the left and right sides of the blotches off set. The sides have 9-16 dusky lateral spots that are vertically elongate, especially anteriorly. Lateral scales are delicately outlined in black, giving a faint dusky appearance. There are numerous black spots anterior to the eye and extending unto the snout. The cheeks and opercles are iridescent silver to blue. The undersides of the head and body are cream colored to light yellow, with a narrow band of melanophores in the dorsal fins are concentrated along the posterior faces of the fin elements. Melanophores in the dorsal fins are concentrated along the posterior faces of the fin elements. The anal fin has few scattered dark spots near the base, and there are scattered spots on the paired fins. Pectoral and pelvic fin membranes are cream colored to yellow, and the base of the caudal fin is whitish to yellow. Males have black submarginal bands in the spinous and soft dorsal fins and also on the caudal fin; soft dorsal and caudal fins may also have black marginal bands. Dark spots on the pelvic fins are also more numerous in males (Williams 1975; Ross 2001).
Counts: 1-7 scale rows above, 6-12 scale rows below the lateral line; 15-21 (10-21) transverse scale rows; 20-25 scale rows around caudal peduncle; 58-79 lateral line scales, 11-12 (8-14 dorsal spines, 8-12 dorsal rays, 1 anal spine, 9 (7-10) anal rays, 14-15 (13-17) pectoral rays (Williams 1975; Ross 2001).
Body shape: Elongate, subcylindrical; body width slightly less than body depth; maximum body depth under the middle of spinous dorsal fin; broad, flat head (Ross 2001). Body depth contained in standard length more then seven times (Hubbs et al.1991).
Mouth position: Terminal or slightly subterminal (Goldstein and Simon 1999).
External morphology: Scales not restricted to lateral line region; belly naked; preopercle smooth or weakly serrate; upper jaw not extending as far as to below middle of eye (Hubbs et al.1991). Lateral line straight, with little or no posterior deflection. May have embedded scales on the prepectoral area and edges of breast. Males develop breeding tubercles on undersides of pelvic rays and anal rays (Williams 1975; Ross 2001).
Distribution (Native and Introduced)
U.S. distribution: Native to the tributaries of the lower Mississippi River Basin (Hubbs et al.1991). Centered in central portion of former Mississippi embayment. West of Mississippi River known from Calcasieu, Sabine, Neches, Trinity, San Jacinto, Red, Ouachita, Arkansas, White, and St. Francis drainages. In eastern tributaries inhabits Hatchie, Yazoo, Big Black, Bayou Pierre, Pearl, Biloxi Bay, and Pascagoula Bay drainages. Generally a Coastal Plain inhabitant, though species extends beyond this boundary in large rivers (Williams 1975; Stauffer and Hocutt 1980).
Texas distribution: Occurs from the San Jacinto to the Sabine Rivers in the eastern part of the state (Hubbs et al.1991). Warren et al. (2000) list this species as occurring in the following drainage units: Red River unit (from the mouth upstream to and including the Kiamichi River), Sabine Lake unit (including minor coastal drainages west to Galveston Bay), Galveston Bay unit (including minor coastal drainages west of mouth of Brazos River).
Abundance/Conservation status (Federal, State, NGO)
Not listed as threatened or endangered by Texas Parks and Wildlife Department
(2006). Species currently stable in the southern United States (Warren 2000).
Macrohabitat: Large creeks to large rivers (Page 1983).
Mesohabitat: Sand substrate (Page 1983); usually collected in slower water (Ross 2001). Mitchell (1987) observed burying behavior of Ammocrypta vivax and felt that one reason for this behavior may be for the fish to conserve energy.
Spawning season: Tuberculate males known from mid-April through mid-August (Williams 1975). Only report of a female reproductive date was a ripe female in east Texas on 8 April. Fertilization of darter eggs by a male scaly darter on 5 April (Hubbs 1985). In Louisiana, Mitchell (1987) reported spawning from April-August, as air temperature ranged from 21.5-29.8 degrees C, and water temperatures ranged from 16.9-26.0 degrees C.
Fecundity: In Arkansas, females collected in late May by Etnier and Starnes (1993) contained 60-70 ova per female. In Louisiana, mean diameter of larger ova ranged from 0.946±2.112% (n=13) in April 1986 to 0.113% (n=1) in October 1986; mean number of mature ova in reproductive females which had not begun to shed eggs was 71±17 (n=14); number of mature ova per female = 43-108 (Mitchell 1987).
Age at maturation: Mitchell (1987) collected specimens from Upper Kisatchie Bayou Drainage (Natchitioches Parish), Louisiana, reporting that all specimens were mature by 39.0 mm SL.
Growth and population structure: Females collected from Upper Kisatchie Bayou Drainage, Louisiana, outnumbered males 1.6:1; smallest mature male and female collected were 36.2 mm SL and 35.4 mm SL, respectively; mean sizes for sexually mature specimens were 45.0 mm SL for males and 41.1 mm SL for females (Mitchell 1987).
Food habits: Invertivore; benthic. Diet mainly midge larvae and entomostracans (Williams 1975; Etnier and Starnes 1993; Goldstein and Simon 1999).
Phylogeny and morphologically similar fishes
Williams (1975) studied geographic variation and recognized no subspecies. Ammocrypta vivax differs from A. clara in having 10 or more transverse scale rows (versus usually 7 or fewer transverse scales; Ross 2001).
Camallanus oxycephalus, Contracaecum (Mayberry et al. 2000) ; Underwood and Dronen (1984) noted infection of this species from the Upper San Marcos River, Hays Co., Texas, with Cammallanus oxycephalus.
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); Hubbs (1957).]
Boschung, H. T. Jr., and R. L. Mayden. 2004. Fishes of Alabama. Smithsonian Institution, Washington. 736 pp.
Cook, F.A. 1959. Freshwater fishes in Mississippi. Mississippi Game and Fish Commission, Jackson.
Etnier, D.A. and W.C. Starnes. 1993. The fishes of Tennessee. Univ. Tennessee Press, Knoxville.
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.
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 the lower Mississippi Valley. Bull. U.S. Fish Comm. 2:57-75.
Hubbs, C. 1957. Distributional patterns of Texas fresh-water fishes. The Southwestern Naturalist 2(2/3):89-104.
Hubbs, C. 1985. Darter Reproductive Seasons. Copeia 1985(1):56-68.
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.
Mayberry, Lillian F., A.G. Canaris, J.R. Bristol, and S.L. Gardner. 2000. Bibliography of parasite and vertebrate hosts in Arizona, New Mexico, and Texas (1893-1984). University of Nebraska Harold W. Manter Laboratory of Parasitology Web Server. January 11, 2000, published on the World Wide Web. pp. 1-100.
Mitchell, D.R. 1987. Reproductive cycle of the scaly sand darter (Ammocrypta vivax) with notes on other life history characteristics. M.S. Thesis. Northwestern State University of Louisiana. 40 pp.
Ross, S. T. 2001. The Inland Fishes of Mississippi. University Press of Mississippi, Jackson. 624 pp.
Page, L.M. 1983. Handbook of Darters. T.F.H. Publications, Neptune City, NJ. 271 pp.
Pflieger, W.L. 1997. The Fishes of Missouri. Revised Edition. Missouri Department of Conservation. Jefferson City. 372 pp.
Stauffer, J.R. and Hocutt C.H. 1980. Ammocrypta vivax (Hay), Scaly Sand Darter. pp. 621 in D.S. Lee et al. Atlas of North American Freshwater Fishes. N.C. State Mus. Nat. Hist., Raleigh, i-r+854 pp.
Texas Parks and Wildlife Department, Wildlife Division, Diversity and Habitat Assessment Programs. County Lists of Texas' Special Species. [30 May 2006]. Available online at http://gis.tpwd.state.tx.us/TpwEndangeredSpecies/DesktopModules/AcountyCodeKeyForWebESDatabases.pdf
Underwood, H.T., and N.O. Dronen, Jr. 1984. Endohelminths of fishes from the Upper San Marcos River, Texas. The Southwestern Naturalist 29(4):377-385.
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, Conservation. 25(10):7-29.
Williams J.D. 1975. Systematics of the percid fishes of the subgenus Ammocrypta, with descriptions of two new species. Bull. Ala. Mus. Nat. Hist. 1:1-56.