Etheostoma lugoi Norris & Minckley
Tufa darter, dardo de toba
PERCIDAE - perches, pikeperches, and darters
ABSTRACT
Size
38 mm SL as adult female, largest male 35 mm, rarely >35 mm
Conservation Status
Considered endangered by the American Fisheries Society in 1989 (in part).
Distribution
Restricted to spring-fed streams in the southwestern quarter of the Cuatro Ciénegas basin, Coahuila, Mexico, where mostly in the mainstream Rio Mesquites and its immediate tributaries.
Abundance
Rare in strongly flowing, highly localized areas. Its apparent rareness may be due in part to its spotty distribution and the heterogeneity of bottoms it inhabits.
Habitat & Ecology
This fish most often occupies open (unvegetated) although complex bottoms on bars comprised of gravel- to cobble-sized fragments of tufa and tufa stromatolites. Shoals created by formation of these bars promote strong, low-turbulence currents so substrates remain scoured of algae, silt, and detritus. Bottom relief is only a few centimeters, but irregularity of tufa produces diverse crevices and miniature caves for the bottom-dwelling fish as well as habitat for its presumed invertebrate foods
Reproduction
Essentially nothing is known of the reproductive habitats or habitats. Males in apparent breeding coloration have been taken in April.
Threats
Extraction of groundwater within and adjacent to springs reduces downflow water volumes diminishing the available habitat. As with other Cuatro Cienegas fishes, non-indigenous crayfish, molluscs, and perhaps fishes (one, a cichlid of the genus Hemichromis is confirmed as naturalized in an adjacent watershed) may be anticipated to result in ecosystem-level changes that undoubtedly will influence this species in the near future.
Conservation Actions
A substantial proportion of the Cuatro Cienegas basin, including most streams inhabited by this diminutive darter, were set aside in 1994 as a biological preserve. Specific conservation actions are, however, yet to be proposed or implemented.
Conservation Recommendations
Devise and implement conservation actions preventing further loss and change of habitat and prohibit introductions of non-indigenous organisms. Especially needed are provisions to maintain lateral and downflow marshes, which are quickly and permanently drained by canalization of springheads.
Important References
- Anonymous. 1994. Descreto por el que se declara como area natural protegida, con el caracter de area de proteccion de flora y fauna, la region conocida como Cuatrocienengas, con una superficie de 84,347-47-00 hectares, municipio del mismo nombre, Coah. Diario Oficial de la Federation CCXCIV(5): 5-11. Mexico, DF.
- Miller, R. R. 1978. Composition and derivation of the native fish fauna of the Chihuahuan Desert region. Pp. 365-382, in R. H. Wauer & D. Riskind (eds.). Transactions of the Symposium of the Biological Resources of the Chihuahuan Desert Region, United States and Mexico. US Natl. Park Ser. Trans. Proc. Ser. 3(1977). US Gov. Print. Off., Wash., DC.
- Minckley, W. L. 1969. Environments of the Bolson of Cuatro Cienegas, Coahuila, Mexico, with special reference to the aquatic biota. TX Westerm Press, Univ. Texas El Paso Sci. Ser. 2: 1-65.
- ______. 1978. Endemic fishes of the Cuatro Cienegas basin, Coahuila, Mexico. Pp. 383-404, in R. H. Wauer & D. Riskind (eds.). Symposium on the Biological Resources of the Chihuahuan Desert Region, United States and M xico. US Natl. Park Ser. Trans. Proc. Ser. 3(1977). US Gov. Print. Off., Wash., DC.
- ______. 1992. Three decades near Cuatro Cienegas, Mexico: Photographic documentation and a plea for area conservation. Pp. 81-110, in M. R. Sommerfeld & D. M. Kubly (eds.). Limnology and Aquatic Biology of the Southwest, Proceedings of a Special Symposium to Honor Professor Gerald Ainsworth Cole. 34th Annual Meeting of the Arizona-Nevada Academy of Science, Tempe, AZ, 21 April 1990. J. AZ-NV Acad. Sci. 26(2).
- ______. 1994. A bibliography for natural history of the Cuatro Cienegas basin and environs, Coahuila, Mexico. Proc. Desert Fishes Council 25(1993): 47-64.
- Norris, S. M & W. L. Minckley. 1997. Two new species of Etheostoma (Osteichthyes: Percidae) from central Coahuila, northern Mexico. Ichthyological Explorations of freshwaters 8(2): 159-176
- Williams, J. E., J. E. Johnson, D. A. Hendrickson, S. Contreras-Balderas, J. D. Williams, M. Navarro-Mendoza, D. E. McAllister & J. E. Deacon. 1989. Fishes of North America, endangered, threatened or of special concern: 1989. Fisheries (Bethesda, Maryland) 14: 2-20..
Preparator
W. L. Minckley, Department of Zoology, Arizona State University, Tempe, Arizona 85287-1501. 1 June 1998.