Pictures by Chad Thomas, Texas State University-San Marcos
Guadalupe roundnose minnow
Upper waters of Wallace Creek, on of heads of the Medina River, San Saba County, Texas (Cope 1880 in:
Etymology/Derivation of Scientific Name
Dionda – from the Greek Dione, the mother of Venus (Edwards 1999); nigro – black; taeniata – striped (Scharpf 2005).
Hybognathus nigrotaeniatus Cope 1880:37.
Dionda episcopa Wayne 1979; Wayne and Whiteside 1985; Hubbs et al. 1991:18.
Dionda nigrotaeniata Gilbert 1998:120; Warren et al. 2000; Nelson et al. 2004:70, 197-198; Scharpf 2005:16; Schonhuth et al. 2008.
Recognized as valid but unnamed species by Mayden et al. (1992); previously synonymized with Dionda episcopa. Gilbert (1998) determined that nigrotaeniata was an available name for this species.
Maximum size: 90 mm (3.54 in) TL (Wayne 1979).
Coloration: Dorsal region dusky (Cope 1880). Black band through eye to snout; black rounded caudal spot (Cope 1880; Hubbs and Brown 1956; Hubbs et al. 1991). Individuals from the Guadalupe River Basin were described as follows: breeding males observed to have a bright yellow-orange color; however some larger males collected during the non-spawning season were yellow in color; mature females during the spawning season had a slight yellow color but not as bright as the males (Wayne 1979; Wayne and Whiteside 1985).
Counts: Pharyngeal teeth 0,4-4,0 (Hubbs et al. 1991). Counts for specimens examined from Fessenden Spring, Comal River, and the San Marcos River (Guadalupe River Basin) ranged from: 37-38 (34-40) lateral line scales; 8 (7-9) dorsal fin soft rays; 8 (7-9) anal fin soft rays (Wayne 1979).
Mouth position: Subterminal
Body shape: Terete. Dorsal origin-pelvic: above or posterior (Schonhuth et al. 2008). Caudal peduncle depth wide; long postorbital; eye as long as snout; distance from end 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 (described as Dionda episcopa; Hubbs et al. 1991).
Morphology: Breeding males with distinct tubercles present on the head, during the spawning season, and also reported that tubercles were present during other times of the year, but they were not so well developed; two larger females were observed to have a few small tubercles on the head (Wayne 1979; Wayne and Whiteside 1985). 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 (described as Dionda episcopa; Hubbs et al. 1991). Intestine long, more than twice the length of the body (Hubbs et al. 1991).
Distribution (Native and Introduced)
U.S. distribution: Found only in Texas.
Texas distribution: Endemic to the spring-influenced headwaters of the Colorado and Guadalupe river basins (Edwards et al. 2004). Warren et al. (2000), Scharpf (2005), and Schonhuth et al. (2008) listed the following drainage units for distribution of D. nigrotaeniata in the state: Colorado River, San Antonio Bay (including minor coastal drainages west of mouth of Colorado River to mouth of Nueces River).
[Additional literature noting collection of this species from Texas locations includes, but is not limited to the following: Hubbs and Brown (1956); Hubbs (1957).]
Abundance/Conservation status (Federal, State, NGO)
Currently secure (Warren et al. 2000; Scharpf 2005); common and abundant in good environments (Edwards et al. 2004).
Macrohabitat: Primarily restricted to clear spring-fed waters that have slight temperature variations (Brown 1953; Hubbs et al. 1953; Jurgens 1951; Kuehne 1955; Tilton 1961; Wayne 1979).
Mesohabitat: No information at this time.
Spawning season: November - March in central Texas (Tilton 1961). A study at Fessenden Spring (Guadalupe River Basin), Texas, indicated some spawning from January – August with spawning peaks occurring in April and May and in July and August (Wayne 1979; Wayne and Whiteside 1985).
Spawning habitat: No information at this time.
Spawning Behavior: No information at this time.
Fecundity: Based on 50 females containing mature ova collected from Fessenden Spring (Guadalupe River Basin), Texas, fecundity ranged from 2 – 540 with a mean of 164 ova (Wayne 1979; Wayne and Whiteside 1985). In the Comal River, fecundity based on 21 females containing mature ova ranged from 8-584 with a mean with a mean of 195; and in the San Marcos River, fecundity ranged from 238-620 with a mean of 352 based on 5 females containing mature ova
Age/sixe at maturation: Females ≥ 30 mm (1.18 in) SL contained mature ova (Wayne 1979).
Migration: No information at this time.
Growth and Population structure: 80 males and 98 females were collected from Fessenden Spring (Guadalupe River Basin), Texas, with a 0.82:1.00 female to male ratio (Wayne and Whiteside 1985).
Longevity: No information at this time.
Food habits: Vegetation main component of diet (Wayne 1979); schools of D. episcopa observed at Fessenden Spring (Guadalupe River Basin), Texas, observed apparently feeding on green filamentous algae (Wayne 1979).
Phylogeny and morphologically similar fishes
Dionda nigrotaeniata is apparently an ecological equivalent to the roundnose minnow (D. episcopa; found in the Pecos River), and the two species may be closely related (Edwards et al. 2004). Distribution of the following similar species differs from that of D. nigrotaeniata, in Texas: the Devils River minnow (D. diaboli) is found in the Devils River, San Felipe Creek, and Sycamore Creek in Val Verde County, and Pinto Creek in Kinney County; the manantial roundnose minnow (D. argentosa) is found in the Devils River, San Felipe and Sycamore creeks in Val Verde County; and the Nueces roundnose minnow (D. serena) is found in the Nueces River system.
Trematoda: Plagioporus sinitsini, Posthodiplostomum minimum (Klaus 1991; Mathis 1993; Mayberry et al. 2000). The sporozoan Myxobolus sp. and the parasitic copepod Lernaea sp. were external parasites found on fish taken from Fessenden Spring (Guadalupe River Basin), Texas (Wayne 1979).
Commercial or Environmental Importance
No information at this time.
Brown, W.H. 1953. Introduced fish species of the Guadalupe River Basin. Texas Journal of Science 5:245-251.
Cope, E.D. 1880. On the zoological position of Texas. Bull. U.S. Natl. Mus. 17, 1-51.
Edwards, R.J. 1999. Ecological profiles for selected stream-dwelling Texas freshwater fishes II. Report to the Texas Water Development Board. 69 pp.
Edwards, R.J., G.P. Garrett, and N.L. Allan. 2004. Aquifer-dependent fishes of the Edwards Plateau region. Chapter 13, pp. 253-268 in: Mace, R.E., E.S. Angle, and W.F. Mullican, III (eds.). Aquifers of the Edwards Plateau. Texas Water Development Board. 360 pp.
Eschmeyer, W. N. Catalog of Fishes electronic version (23 April 2008): http://www.calacademy.org/research/ichthyology/catalog/fishcatsearch.html
Gilbert, C.R. 1998. Type catalogue of recent and fossil North American freshwater fishes: families Cyprinidae, Catostomidae, Ictaluridae, Centrarchidae and Ellasomatidae. Florida Museum of Natural History, Special Publication 1, University of Florida, Gainesville.
Hubbs, C. 1957. Distributional patterns of Texas fresh-water fishes. The Southwestern Naturalist 2(2/3):89-104.
Hubbs, C., and W.H. Brown. 1956. Dionda diaboli (Cyprinidae), a new minnow from Texas. Southwestern Naturalist 1:69-77.
Hubbs, C., R.A. Kuehne, and J.C. Ball. 1953. The fishes of the upper Guadalupe River, Texas. Texas J. Sci. 5:216-244.
Jurgens, K.C. 1951. The distribution and ecology of the fishes of the San Marcos River. M.A. Thesis, University of Texas, Austin.
Klaus, B. 1991. A survey of the endoparasitic helminthes of Dionda episcopa, the roundnose minnow, and Astyanax mexicanus, the Mexican tetra, from the San Marcos and Comal Rivers, Texas. M.A. Thesis, Southwest Texas State University, San Marcos.
Kuehne, R.A. 1955. Stream surveys of the Guadalupe and San Antonio Rivers. Texas Game and Fish Com., IF Report Ser. 1:1-56.
Mathis, S.D. 1993. A morphometric study of Plagioporus sinitsini Mueller (Digenea: Opecoelidae) from the gallbladder of three Cyprinid hosts from the Blanco, San Marcos, and Comal Rivers in central Texas. Master of Science Thesis, Southwest Texas State University, San Marcos. 44 pp.
Mayberry, L.F., A.G. Canaris, J.R. Bristol, and Scott L. Gardner. 2000. Bibliography of parasites and vertebrate host in Arizona, New Mexico and Texas (1893-1984). University of Nebraska Harold W. Manter Laboratory of Parasitology Web Server, published on the World-Wide-Web, 100 pp.
Mayden, R.L., Matson, R.H., Hillis, D.M., 1992. Speciation in the North American Genus Dionda (Teleostei: Cypriniformes). In: Mayden, R.L. (Ed.), Systematics, Historical Ecology and North American Freshwater Fishes. Standford University Press, California, pp. 710–746.
Nelson, J.S., E.J. Crossman, H. Espinoza-Perez, L.T. Findley, C.R. Gilbert, R.N. Lea, and J.D. Williams. 2004. Common and Scientific Names of Fishes from the United States, Canada, and Mexico. American Fisheries Society, Special Publication 29, Bethesda, Maryland.
Scharpf, C. 2005. Annotated checklist of North American freshwater fishes including subspecies and undescribed forms, Part 1: Petromyzontidae through Cyprinidae. American Currents, Special Publication 31(4):1-44.
Schonhuth, S., I. Doadrio, O. Dominguez-Donminguez, D.M. Hillis, and R.L. Mayden. 2008. Molecular evolution of southern North American cyprinidae (Actinopterygii), with the description of the new genus Tampichthys from central Mexico. Molecular Phylogenetics and Evolution 47(2008):729-756.
Tilton, J.E. 1961. Ichthyological survey of the Colorado River of Texas. M.A. Thesis, University of Texas, Austin.
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, Conservation. 25(10):7-29.
Wayne, L.M. 1979. Ecology of the roundnose minnow, Dionda episcopa (Osteichthyes: Cyprinidae) from three central Texas springs. M.S. Thesis, Southwest Texas State University, San Marcos. 50 pp.
Wayne, L.M., and B.G. Whiteside. 1985. Reproduction data on Dionda episcopa from Fessenden Spring, Texas. Texas Journal of Science 37(4):321-328.