Lake Ponchartrain, New Orleans, Louisiana (Lesueur 1821).
Etymology/Derivation of Scientific Name
Poecilia, from Greek poikilos (Latinized stem poecil), meaning “variegated, speckled;” latipinna, from Latin latus (stem lat), meaning “wide, broad” and pinna, meaning “fin” (Boschung and Mayden 2004).
Mollinesia latipinna Lesueur 1821:3.
Mollienisia latipinna Evermann 1899:309; Cook 1959:158.
Maximum size: 150 mm TL (Burgess 1980).
Coloration: Dark spots on scales obscure diamond-shaped color pattern (Hubbs et al 1991). Back is dark olive green; sides lighter yellow, green, or brown; undersides of head and body silvery white. 6-8 rows of square to rectangular dark brown spots on sides. Lateral scales outlined by pigment, resulting in cross-hatched pattern, which is more apparent in smaller fish. Large breeding males with a reddish orange marginal band on the enlarged dorsal fin, and a reddish orange spot centered on the upper half of the caudal fin. Caudal fin has dusky marginal band, especially prominent along upper and lower margins (band often faint). Upper part of caudal fin has several rows of dark spots. Dorsal fin has numerous dark bars forming an even reticulate pattern basally, which becomes more broken distally. Sides with iridescent blue-green spots between the horizontal rows of dark brown spots. Sides of head and pectoral area with gold sheen. Females also have 3-4 rows of spots in the dorsal fin. Caudal fin with dusky tinge, lacking a more distinct marginal band. As in the male, pectoral, anal, and pelvic fins are clear, with small melanophores along the fin rays (Ross 2001).
Counts: 25-29 lateral line scales; 7-9 anal rays; 11-13 pectoral rays; 6-7 pelvic rays (Ross 2001); 12-14 dorsal fin rays (Hubbs et al. 1991).
Body shape: Strongly compressed body, especially in the area of the caudal peduncle. Large fish are proportionately deeper bodied
Mouth position: Superior (Ross 2001).
External morphology: Dorsal fin base more than one-half predorsal length; origin of dorsal fin anterior to origin of anal fin (Hubbs et al 1991). In large males, anal fin modified into gonopodium. In males, second ray of pelvic fin is elongated (Ross 2001). Dorsal fin enlarged in males greater than 45 mm SL; males from 30-45 mm SL show some enlargement of the dorsal fin; males less than 30 mm SL do not develop enlarged dorsal fin and tend to resemble females (Snelson 1985).
Internal morphology: Teeth not moveable (Hubbs et al. 1991); teeth in several rows, with the outer row larger (Ross 2001).
Distribution (Native and Introduced)
U.S. distribution: Primarily found in coastal waters from North Carolina to the northeastern Mexico (Hubbs et al. 1991).
Texas distribution: Known from numerous inland localities, primarily in spring-influenced central Texas headwaters and in the lower Rio Grande; reports argue that all Texas inland localities are native (Burgess 1980). Brown (1953) and Hubbs et al. (1991) stated that upper Guadalupe River and San Marcos River populations represent introductions. Warren et al. (2000) list the following drainage units for distribution of Poecilia latipinna in the state: Sabine Lake (including minor coastal drainages west to Galveston Bay), Galveston Bay (including minor coastal drainages west to mouth of Brazos River), Brazos River, Colorado River, San Antonio Bay (including minor coastal drainages west of mouth of Colorado River to mouth of Nueces River), Nueces River.
Abundance/Conservation status (Federal, State, NGO)
Populations in southern drainages currently stable (Warren et al. 2000).
Macrohabitat: Springs, lakes and ponds, rivers and streams, drainage ditches, and salt marshes (Burgess 1980).
Mesohabitat: Edges of streams or ponds, usually near vegetation, in shallow protected water, rather than open areas (Ross 2001). Can withstand a wide range of salinity, but more common below 7 ppt. Breeding populations can occur in brackish or fresh water (Gunter 1950; Hellier 1967). Can survive low oxygen levels by reducing oxygen consumption rates and by using flattened head and superior mouth position to draw water from oxygen-rich surface film (Lewis 1970; Peterson 1990). One of several species dominate in the upstream assemblage of the lower Rio Grande River (Edwards and Contreras-Balderas 1991).
Spawning season: In Florida, from April – June, and again from August – October (Snelson 1984).
Reproductive strategy: Live-bearer; courtship and copulation occur rapidly, female capable of storing sperm (Moyle 1976; Burgess 1980). Large males (generally over 45 mm SL) use brightly-colored enlarged dorsal fins to attract females (Snelson 1985). Traits that indicate female fecundity may be used by males as cues in male mate choice (Aspbury and Gabor 2004). Male sexual behavior toward females dramatically increased immediately after they gave birth. Males displayed higher rates of sexual behavior toward virgin females than toward gravid females (Farr and Travis 1986).
Fecundity: Broods range from 6-36, depending upon the size of the female. Broods are produced every 21-68 days depending on time spent in egg development, and the rate at which egg yolk is added (Trexler 1985; Snelson et al 1986). Large female can produce up to 141 young (9-12 mm TL) in a brood (Moyle 1976). Presence of sexually mature females increases amount of sperm males have for insemination (effect strongest in small males; Aspbury and Gabor 2004).
Age at maturation: Occurs quickly; males born in spring may breed in late summer; more often, fish continue growing and do not breed until next spring (Snelson 1984).
Growth and Population structure: Females generally outnumber males (Moyle 1976). Early in life, growth rate similar for males and females; for males, growth rates generally decline with onset of sexual maturity, but these rates can be highly variable (Snelson 1982). Males greater than 45 mm SL are generally found in less dense populations; at higher population densities, males are usually smaller than 45 mm SL (Snelson 1985).
Longevity: Males may live 11 months or less reaching sexual maturity (Snelson 1982).
Food habits: Omnivorous: feeds on green algae, diatoms and other plant material, as well as animal material: rotifers, small crustaceans (such as copepods and ostracods) and aquatic insects; at times, may heavily predate mosquito larvae and pupae; larger fish eat more plant material (Hunt 1953; Harrington and Harrington 1961); invertebrates eaten only when greatly abundant, even then mainly consumed by smaller fish (Harrington and Harrington 1961).
Phylogeny and morphologically similar fishes
The genus Poecilia is in the tribe Poeciliini, which also includes the North American genus Xiphophorus (Parenti and Rauchenberger 1989). Expanded dorsal fin of large male Poecilia latipinna highly distinctive. Small males, females, juveniles could be confused with mosquitofishes (such as Gambusia affinis) or with small topminnows, such as the rainwater killifish (Lucania parva). The sailfin molly differs from both in having distinct horizontal rows of spots on the sides, and differs from all killifishes by having internal fertilization (males possess a gonopodium), and by having the third anal ray unbranced in females. Poecilia latipinna differs from mosquitofishes in lacking a distinct teardrop marking under the eye and in having the dorsal fin origin anterior to the origin of the anal fin (Ross 2001).
Cestoda: Cysticercoides; Trematoda: Ascocotyle, Ascocotyle chandleri, Ascocotyle leighi, Ascocotyle leighi metacercaria, Ascocotyle mollienisicola, Saccocoelioides sogandares; Acanthocephala: Atactorhynchus verecendus (Mayberry et al. 2000).
Commercial or Environmental Importance
[Additional literature noting collection of this species from Texas locations includes, but is not limited to the following: Brazos River (Winemiller et al. 2004).]
Aspbury, A.S., and C.R. Gabor. 2004. Differential sperm priming by male sailfin mollies (Poecilia latipinna): Effects of female and male size. Ethology 110(3):193-202.
Boschung, H.T., Jr., and R.L. Mayden. 2004. Fishes of Alabama. Smithsonian Books, Washington, 736 pp.
Brown, W.H. 1953. Introduced species in the Guadalupe River basin. Texas Journal of Science, 5:245-251.
Burgess, G.H. 1980. Poecilia latipinna (Lesueur), Sailfin molly. P. 549 in D.S. Lee, et al. Atlas of North American Freshwater Fishes. N. C. State Mus. Nat. Hist., Raleigh, i-r+854 pp.
Cook, F.A. 1959. Freshwater fishes in Mississippi. Mississippi Game and Fish Commission, Jackson. 239 pp.
Edwards, R.J., and S. Contreras-Balderas. 1991. Historical changes in the Ichthyofauna of the Lower Rio Grande (Rio Bravo del Norte), Texas and Mexico. The Southwestern Naturalist 36(2): 201-212.
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.
Farr, J.A., and J. Travis. 1986. Fertility advertisement by female sailfin mollies, Poecilia latipinna (Pisces: Poeciliidae). Copeia 1986(2):467-472.
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.
Harrington, R.W., Jr., and E.S. Harrington. 1961. Food selection among fishes invading a high subtropical salt marsh: from onset of flooding through the progress of a mosquito brood. Ecology 45(4):646-666.
Hellier, T.R., Jr., 1967. The fishes of the Santa Fe River system. Bull. Fla. State Mus. Biol. Ser. 2(1):1-46.
Hubbs, C., R.J. Edwards, and G.P. Garrett. 1991. An annotated checklist to the freshwater fishes of Texas, with keys to identification of species. The Texas Journal of Science, Supplement, 43(4):1-56.
Hunt, B.P. 1953. Food relationships between Florida spotted gar and other organisms in the Tamiami Canal, Dade Country, Florida. Trans. Amer. Fish. Soc. 82(1952):12-33.
Lesueur, C.A. 1821. Description of a new genus, and of several new species of fresh water fish, indigenous to the United States. J. Acad. Nat. Sci. Phil. 2:2-8.
Lewis, W.M., Jr., 1970. Morphological adaptations of cyprinodontids for inhabiting oxygen deficient waters. Copeia 1970(2):319-326.
Mayberry, L.F., A.G. Canaris, and J.R. Bristol. 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 pp. 1-100.
Moyle, P.B. 1976. Inland Fishes of California. University of California Press, Berkeley. 405 pp.
Parenti, L.R. and M. Rauchenberger. 1989. Systematic overview of the poeciliines, pp. 3-12. In: Ecology and evolution of livebearing fishes (Poeciliidae). G. K. Meffe and F. F. Snelson, Jr., eds. Prentice Hall, Englewood Cliffs, N.J. 453 pp.
Peterson, M.S. 1990. Hypoxia-induces physiological changes in mangrove swamp fishes: sheepshead minnow Cyprinodon variegatus Lacepede and sailfin molly Poecilia latipinna (Lesueur). Comp. Biochem. Physiol. 97A(1):17-21.
Ross, S.T. 2001. The Inland Fishes of Mississippi. University Press of Mississippi. 624 pp.
Snelson, F.F., Jr., 1982. Indeterminate growth in males of the sailfin molly, Poecilia latipinna. Copeia 1982(2):296-304.
Snelson, F.F., Jr., 1984. Seasonal maturation and growth of males in a natural population of Poecilia latipinna. Copeia 1984(1):252-255.
Snelson, F.F., Jr. 1985. Size and morphological variation in males of the sailfin molly, Poecilia latipinna. Env. Biol. Fish. 13(1):35-47.
Snelson, F. F., Jr., J. D. Wetherington, and H.L. Large. 1986. The relationship between interbrood interval and yolk loading in a generalized poeciliid fish, Poecilia latipinna. Copeia 1986(2):295-304.
Trexler, J. C. 1985. Variation in the degree of viviparity in the sailfin molly Poecilia latipinna. Copeia 19885(4):999-1004.
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.
Winemiller, K.O., F.P. Gelwick, T.H. Bonner, S. Zueg, and C. Williams. 2004. Response of oxbow lake biota to hydrologic exchanges with the Brazos River channel. Report to the Texas Water Development Board. 59 pp.