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Hybopsis amnis
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 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: 1 ,4-4, 1;
teeth without prominent parallel grooves (Hubbs et al 1991)usually seven
anal fin rays; fewer than 45 lateral line scales; fewer than 10 soft rays on
dorsal fin (Hubbs et al 1991); 33-38 lateral scales (Page and Burr 1991).
Body shape: Fairly
compressed body (Page and Burr 1991).
Mouth position:
Subinferior and horizontal (Hubbs et al 1991).
External 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; upper sides of body
without scattered giant melanophores; lateral line scales not markedly
elevated anteriorly, height one to two times width; lateral line complete;
last ray of dorsal fin much less than one-half the length of the longest;
interradial membranes of dorsal fin without melanophores (except along edge
of rays or forming a dash on the anterior two membranes); predorsal scales
not crowded; 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; no maxillary barbell present; 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; 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; dorsal
and anal fins without spines (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 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, NGO)
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-silty 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:
Spawning Behavior:
Males develop large tubercles on head and snout (Clemmer 1980).
Fecundity:
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:
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 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 by August and
that longer individuals collected at that time are age 1. The two largest
individuals (53 and 54 mm 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 at the first and second annuli,
respectively, based on tentative sale 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:
Phylogeny and morphologically similar fishes
Closely related species
Hybopsis amblops, H. winchelli (closest relative), H. lineapunctata,
and H. rubrifrons (Clemmer 1980). Close relationship between
Hybopsis amnis and H. winchelli (Grose and Wiley 2002). H.
winchelli differs from H. amnis in that it almost always has
barbel at the corner of the mouth; flatter, longer head; black caudal spot;
and fewer, larger tubercles on head of breeding male (Page and Burr 1991).
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
Commercial or Environmental Importance
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.
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