Type series from Dickinson Bayou, Dickinson, TX; Buffalo Bayou, Houston, TX; and Oso Creek, Corpus Christi, TX (Evermann 1892).
Etymology/Derivation of Scientific Name
Fundulus: from fundus, meaning bottom, though fishes of this group are largely surface oriented; pulvereus: powdery (Ross 2001).
Zygonectes pulvereus Evermann 1892:85.
Fundulus pulvereus Everman 1899:309; Cook 1959:148.
Maximum size: 65 mm TL (Hardy 1980).
Coloration: Simpson and Gunter (1956) described coloration for specimens collected in Texas: Base color of females olive to dark gray-blue above, shading to gold on sides and to silvery or cream on belly; large discrete dark dots scattered over body, chiefly confined to area above midline or slightly below (dotting quite variable); some females with faint, broken horizontal stripes; fins pale to dusky and pectorals yellowish at base; suborbital occasionally golden. Males with 12-17 bluish vertical stripes, with silvery interfaces of same width; fainter horizontal stripes sometimes present; olive on back and silvery on belly; black and white horizontal stripes on posterior portion of dorsal; anal and dorsal fins dusky, or anal sometimes yellowish dusky; caudal fin dusky yellowish; dorsal ocellus clear, faint, or absent. Hubbs et al. (1991) noted the following information regarding coloration: predorsal stripe reaching occiput; dark markings on scales not concentrated at posterior edge; no noticeable cross-hatched pattern; no dark subocular bar; body mottled, barred, or irregularly spotted; body barred or not, but never with a dark spot on dorsal part of caudal peduncle; body without a distinct dark lateral band. Simpson and Gunter (1956) and Blackburn and Klee (1963) described a blue phase for the species in Texas, females having a dark gray blue above, and males with bluish vertical stripes.
Counts: 15+ scale rows from pelvic fin origin to isthmus; 30-40 longitudinal scale rows (Hubbs et al 1991); 5-7 gillrakers; 9-10 anal rays; 10 dorsal rays; 14-16 pectoral rays; 6 pelvic rays; 11 preoperculomandibular pores; 4 mandibular pores (Ross 2001).
Body shape: Small bodied with a strongly convex dorsal profile; body depth increases relative to standard length; head length goes into standard length 2.9-3.4 (Ross 2001).
Mouth position: Slightly superior (Ross 2001).
External morphology: Dorsal fin originating anterior to anal fin origin; eye contained fewer than one and one-half times in snout; gill slit extending dorsal to uppermost pectoral fin ray. Distance from origin of dorsal fin to end of hypural plate less than distance from origin of dorsal fin to preopercle or occasionally about equal to that distance (Hubbs et al. 1991).
Distribution (Native and Introduced)
U.S. distribution: Species ranges from Corpus Christi, Texas to Mobile, Alabama, on Gulf Coast and from St. John’s River, Florida, to lower York River, Virginia, on Atlantic slope; wide zone of hybridization (or intergradation) between F. pulvereus and the marsh killifish (F. confluentus) on Gulf Coast and narrow zone in northeastern Florida (Hardy 1980).
Texas distribution: Occurs in coastal waters and short distances inland from about Corpus Christi to Sabine Lake (Hubbs et al. 1991).
Abundance/Conservation status (Federal, State, NGO)
Populations in the southern United States are currently stable (Warren et al. 2000).
Macrohabitat: Occurs in brackish marshes, bayous, freshwater rivers, and rice fields on Gulf Coast, and barrier beach ponds on Atlantic slope (Hardy 1980). Found in bayous and marshes on the Gulf Coast of Mississippi, in fresh and brackish water (Cook 1959).
Mesohabitat: Found in medium to low salinity habitats of coastal marshes in salinities ranging from .3-47.6 ppt; able to survive at least two months in fresh water (Gunter 1950; Griffith 1974; Miller and Guillory 1980). In the Aransas National Wildlife Refuge, Texas, species seemed to prefer sheltered, brackish waters, and were collected in salinities ranging from 0.4-16.0 ppt (Gunter 1950). Specimens collected on the Texas coast in salinities of 30.1 ppt, 44.8 ppt, and 53.9 ppt (Simpson and Gunter 1956), in water temperatures ranging from 17-34.5 degrees C (Simpson and Gunter 1956; Nordlie 2006). In Alabama, experimental lower salinity limit was freshwater, and the experimental upper salinity limit ranged from 95.6-106.4 (Griffith 1974; Nordlie 2006). In MO, lower lethal DO limit, mg kgˉ¹ was 0.88 ± 0.23, 26 degrees C, fresh water (Smale and Rabeni 1995; Nordlie 2006). In TX, observed range of DO, mg kgˉ¹ was <5 (Gelwick et al. 2001; Nordlie 2006).
Biology Food habits and reproductive pattern of Fundulus pulvereus are likely similar to that of the closely related marsh killifish (Fundulus confluentus; Ross 2001; Boschung and Mayden 2004), a species whose range does not include Texas.
Spawning season: Based on data obtained from dissection of females collected in October, November, and January, species believed to spawn in fall and winter, and perhaps other seasons, on the Texas coast (Simpson and Gunter 1956; Nordlie 2006). On the Mississippi coast, during late March, specimens up to 29 mm SL were collected, containing fully developed eggs measuring 1.5 mm in diameter (Cook 1959). Greeley (1984) reported that Fundulus pulvereus apparently spawns only during the 3-day to 6-day periods of the biweekly or semilunar spring tides.
Spawning location: In aquaria, nylon mops utilized for spawning; eggs also deposited in large pores of corks (Blackburn and Klee 1963; Boschung and Mayden 2004).
Reproductive strategy: Low frequency sound is produced by male as he circles female from a distance; somewhat later, higher frequency sounds are produced when male positions his body either above or below that of the female in an effort to direct the female to suitable substrate for spawning (Drewry 1962; Foster 1967). In aquaria, nylon mops were used as suitable spawning location; male was observed to swim beneath the female, directing the female toward the mop; female would occasionally turn her vent upward as she neared the mop, while male remained below her; many eggs drifted to bottom, being only moderately adherent (Blackburn and Klee 1963; Boschung and Mayden 2004).
Fecundity: Average diameter of ripe eggs 1.6 mm (Greely 1984). Eggs from southern Louisiana stock often require 3-4 weeks before hatching (Foster 1967). In aquaria, 40 eggs laid in 1 day; eggs moderately adhesive (Blackburn and Klee 1963; Boschung and Mayden 2004).
Age at maturation: Based on collection of fish on the Mississippi coast, no longer than 29 mm SL, and containing fully developed eggs, sexual maturity is reached by 1 year old (Cook 1959; Boschung and Mayden 2004).
Growth and Population structure: Simpson and Gunter (1956) examined 50 adult specimens, of which males ranged from 30-46 mm long, and females were 16-45 mm long.
Food habits: Stomach contents of two specimens collected on the Texas coast yielded aquatic insects from one specimen, and two isopods (each about 1.0 mm in length) from the other (Simpson and Gunter 1956).
Phylogeny and morphologically similar fishes
Fundulus pulvereus is in the subgenus Fundulus (Wiley 1986). F. pulvereus differs from F. chrysotus (golden topminnow) in lacking red spots on the side and fins (Boschung and Mayden 2004).
Calyptospora funduli (Apicomplexa: Calyptosporidae; Fournie and Overstreet 1993); Stictodora cursitans n. comb. (Trematoda: Heterophyidae; Kinsella and Heard 1974).
Commercial or Environmental Importance
[Additional literature noting collection of this species from Texas locations includes, but is not limited to the following: Hubbs (1957); Akin et al. (2003).]
Akin, S., K.O. Winemiller, F.P. Gelwick. Seasonal and spatial variations in fish and macrocrustacean assemblage structure in Mad Island Marsh estuary, Texas. Estuarine, Coastal and Shelf Science 57(2003):269-282.
Blackburn, A., and A.J. Klee. 1963. A beautiful backyard “import”, the bayou killifish. Aquarium 32(8):28-31.
Boschung, H.T., Jr., and R.L. Mayden. 2004. Fishes of Alabama. Smithsonian Books, Washington, D.C. 736 pp.
Cook, F.A. 1959. Freshwater fishes in Mississippi. Mississippi Game and Fish Commission, Jackson. 239 pp.
Drewry, G.E. 1962. Some observations of courtship behavior and sound production in five species of Fundulus. M.A. Thesis, University of Texas. 71 pp.
Evermann, B.W. 1892. A report upon investigations made in Texas in 1891. Bull. U.S. Fish Comm. 11:61-90.
Evermann, B.W. 1899. Report on investigations by the U.S. Fish Commission in Mississippi, Louisiana, and Texas, in 1897. Rept. U.S. Fish Comm. 24:287-310.
Fournie, J.W., and R.M. Overstreet. 1993. Host specificity of Calyptospora funduli (Apicomplexa: Calyptosporidae) in Atheriniform fishes. Journal of Parasitology 79(5):720-727.
Foster, N.R. 1967. Comparative studies on the biology of killifishes (Pisces: Cyprinodontidae). Ph.D. diss. Cornell Univ., Ithaca, N.Y. 391 pp.
Gelwick, F.P., S. Akin, D.A. Arrington, and K.O. Winemiller. 2001. Assemblage structure in relation to environmental variation in a Texas Gulf Coastal wetland. Estuaries 24(2):285-296.
Greeley, M.S., Jr. 1984. Spawning by Fundulus pulvereus and Adinia xenica (Cyprinodontidae) along the Alabama Gulf Coast is associated with the semilunar tidal cycles. Copeia 1984(3):797-800.
Griffith, R.W. 1974. Environment and salinity tolerance in the genus Fundulus. Copeia 1974(2):319-331.
Gunter, G. 1950. Distributions and abundance of fishes on the Aransas National Wildlife Refuge, with life history notes. Publ. Inst. Mar. Sci., Univ. Tex. 1(2):89-101.
Hardy, J.D., Jr. 1980. Fundulus pulvereus (Evermann), Bayou killifish. pp. 525 in D. S. Lee et al., Atlas of North American Freshwater Fishes. N. C. State Mus. Nat. Hist., Raleigh, i-r+854 pp.
Hubbs, C. 1957. Distributional patterns of Texas fresh-water fishes. The Southwestern Naturalist 2(2/3):89-104.
Hubbs, C., R. J. Hubbs, and G.P. Garrett. 1991. An annotated checklist of the freshwater fishes of Texas, with keys to the identification of species. Texas Journal of Science, Supplement 43(4):1-56.
Kinsella, J.M., and R.W. Heard, III. 1974. Morphology and life cycle of Stictodora cursitans n. comb. (Trematoda: Heterophyidae) from mammals in Florida salt marshes. Transactions of the Microscopical Society 93(3):408-412.
Miller, C. and V. Guillory. 1980. A comparison of marsh fish communities using the Wegener ring. Proc. S.E. Assoc. Fish Wildl. Agencies 34:223-233.
Nordlie, F.G. 2006. Physiochemical environments and tolerances of cyprinodontoid fishes found in estuaries and salt marshes of eastern North America. Rev. Fish. Biol. Fisheries 16(1):51-106.
Ross, S.T. 2001. The Inland Fishes of Mississippi. University Press of Mississippi, Jackson. 624 pp.
Simpson, D.G., and G. Gunter. 1956. Notes on habitats, systematic characteristics and life histories of Texas salt water Cyprinodontes. Tulane Studies in Zoology 4(4):115-134.
Smale, M.A., and C.F. Rabeni. 1995. Hypoxia and hyperthermia tolerances of headwater stream fishes. Trans. Amer. Fish. Soc. 124:698-710.
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.
Wiley, E.O. 1986. A study of the evolutionary relationships of Fundulus topminnows (Teleostei: Fundulidae). Amer. Zool. 26:121-130.