|
Picture by Chad Thomas, Texas State University-San Marcos |
||
|
pallid shiner
Type Locality Mississippi River, 1.7 km n of Prairie du Chien, Crawford Co., WS (Hubbs and Greene 1951).
Etymology/Derivation of Scientific Name Hybopsis, meaning “rounded face;” amnis, meaning “stream or river” (Etnier and Starnes 1993).
Synonymy Notropis amnis Hubbs and Greene 1951. The first specimens of N. amnis to be named and recorded were collected by Jordan and Gilbert in 1884 in Comal River at New Braunsfels, Texas, and were included in a composite series and assigned the manuscript name Notropis nocomis (Hubbs 1951).
Characters Maximum size: 70 mm (2.76 in) SL (Clemmer 1980).
Life colors: No pronounced dark markings on dorsal fin membranes (Hubbs et al 1991); straw yellow above; scales usually dark-edged; black stripe along silver side and around snout, stripe darkest at rear, absent in turbid water; sometimes a black caudal spot (Page and Burr 1991).
Counts: Pharyngeal teeth 1 ,4-4, 1 (Hubbs et al. 1991; Page and Burr 1991); 33-38 lateral line scales (Page and Burr 1991). Usually 7 anal fin soft rays; fewer than 10 dorsal fin soft rays (Hubbs et al 1991).
Body shape: Slim. Fairly compressed body (Page and Burr 1991).
Mouth position: Subterminal and horizontal (Hubbs et al 1991).
Morphology: Depressed dorsal fin longer than head; distance from corner of mouth to posterior end of maxillary about equal to distance from corner of mouth to tip of mandible; eye larger, equal to or longer than snout and contained three and one-half or fewer times in head length; last ray of dorsal fin much less than one-half the length of the longest; 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 fleshy lobes; 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; distance from origin of anal fin to end of caudal peduncle contained two and one-half or fewer times in distance from tip of snout to origin of anal fin; (Hubbs et al 1991). Breeding males have tubercles concentrated on lower half of head (Page and Burr 1991).
Distribution (Native and Introduced) U.S. distribution: Ranges widely throughout the Mississippi River basin southward along the Gulf Coastal Plain in Texas to the Guadalupe Basin (Hubbs et al 1991).
Texas distribution: Often found in small rivers in east Texas (Page and Burr 1991). Common in the streams of eastern Texas and penetrates westward in the Trinity River as far as Dallas (Hubbs 1951). The Williams et al. (2005) study of the Sabine River drainage within the PRTA (Peason Ridge Training Area) in west-central Louisiana showed the species to be absent from recent collections, differing from historical species accounts for the drainage.
Abundance/Conservation status (Federal, State, Non-governmental organizations) Populations in southern drainages are currently vulnerable (Warren et al. 2000).
Habitat Associations Macrohabitat: Prefers medium to large rivers and streams (Clemmer 1980; Hubbs 1951). A study by Moriarty and Winemiller (1997) found individuals occupying habitats ranging from backwaters to sandbanks in Village Creek, a blackwater stream of the Gulf coastal plain in east Texas, Hardin County.
Mesohabitat: Quiet waters over sand-silt bottoms, often at end of sand and gravel bars; intolerant of heavy siltation and pollutants (Clemmer 1980). Year class strength seems to vary as a function of stream discharge, which may support the idea: floodplain access is important for successful spawning or survival of young fish (Kwak 1991). Wide ecological tolerance is shown, but excessive turbidity seems to be a barrier (Hubbs 1951).
Biology Life history of the pallid shiner is virtually unknown. Nothing is known about the spawning or food habits of this species (Kwak 1991).
Spawning season: In Texas, H. amnis showed length-frequency distributions consistent with late spring-early summer (May-June) spawning (Moriarty and Winemiller 1997). Clemmer (1980) states that spawning occurs in late winter and early spring in southern portions of its range and that ripe adults have been collected as late as March in the Mississippi River in Arkansas.
Spawning habitat: No information at this time.
Spawning Behavior: Males develop large tubercles on head and snout (Clemmer 1980).
Fecundity: No information at this time.
Age at maturation: Review of available life history information for small cyprinids, in Becker (1983), indicates that most species mature at age 1. The relatively small size and short life span of the species suggest that it also follows this trend (Kwak 1991).
Migration: No information at this time.
Growth and Population Structure: A study by Kwak (1991), from the Kankakee River, Illinois, states that length-frequency distribution of pallid shiners from all years indicates that at least two distinct size-classes exist during July and August. Two dominant size-groups are separated by the low number of individuals in the 34-36 mm (1.34-1.42 in) range during that period. The two distinct size-groups most likely correspond to different age-classes, suggesting that juvenile (age 0) pallid shiners attain a TL of up to 36 mm (1.42 in) by August and that longer individuals collected at that time are age 1. The two largest individuals (53 and 54 mm, 2.09 and 2.43 in, TL) collected in November may represent a third age-class (age 2) or additional growth of age-1 individuals from August to November. These results are consistent with the findings of Becker (1983), who estimated total lengths of 34 and 49 mm (1.34 and 1.93 in) at the first and second annuli, respectively, based on tentative scale readings of seven pallid shiners collected from the Mississippi River.
Longevity: 2 to 3 years in Wisconsin and Illinois (Becker 1983; Kwak 1991).
Food habits: No information at this time.
Phylogeny and morphologically similar fishes Hubbs (1951) studied intrespecific variation in N. amnis and recognized two subspecies, those being N. a. amnis from the Mississippi Valley region, and N. a. pinosa from southwestern states.
Host Records No information at this time.
Commercial or Environmental Importance No information at this time.
References Becker, G. C. 1983. Fishes of Wisconsin. University of Wisconsin Press, Madison. 1052 pp. Clemmer, G. H. 1980. Notropis amnis (Hubbs and Greene), Pallid shiner. pp. 224 in D. S. Lee, et al. Atlas of the North American Freshwater Fishes. N. C. State Mus. Nat. Hist., Raleigh, i-r+854 pp. Etnier, Davis A., and Wayne C. Starnes. 1993. The Fishes of Tennessee. The University of Tennessee Press, Knoxville, 681 pp. Grose, M. J., and E. O. Wiley. 2002. Phylogenetic relationships of the Hybopsis amblops species group (Teleostei: Cyprinidae) 4:1092-1097. Hubbs, C. L. 1951. Notropis amnis, a new cyprinid fish of the Mississippi fauna, with two subspecies. Occ. Pap. Mus. Zool. Univ. Mich. 530:1-30. Hubbs, C., R. J. Edwards, and G. P. Garrett. 1991. An annotated checklist of the freshwater fishes of Texas, with keys to identification of species. The Texas Journal of Science, Supplement, 43(4):1-56. Kwak, T. J. 1991.Ecological characteristics of a northern population of the pallid shiner. Trans. Amer. Fish. Soc.120:106-115. 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. Page, L. M., and B. M. Burr. 1991. A Field Guide to Freshwater Fishes of North America, north of Mexico. Houghton Mifflin Company, Boston. 432 pp. Ross, S. T. 2001. The Inland Fishes of Mississippi. University Press of Mississippi, Jackson. 624 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. Williams, L. R., T. H. Bonner, Hudson, J. D., III, M. G. Williams, T. R. Leavy, and C. S. Williams. 2005. Interactive effects of environmental variability and military training on stream biota of three headwater drainages in Western Louisiana. Transactions of the American Fisheries Society 134:192-206.
|
||
 |
||
