Banded killifish
The banded killifish (Fundulus diaphanus) is a small, slender freshwater fish in the family Fundulidae, characterized by an olive-green back, paler underside, and distinctive vertical dark bands along its sides—typically 18 to 22 bold bands in males and 8 to 12 fainter ones in females— with a maximum length of about 13 cm, though commonly reaching 6–8 cm.[1][2][3] Native to eastern North America, the species inhabits quiet, shallow margins of lakes, ponds, and sluggish streams over sand, mud, gravel, or detritus bottoms, often near submerged aquatic vegetation, and it occasionally enters brackish estuarine waters.[1][2] Its range spans the Atlantic Slope from the Pee Dee River in South Carolina northward to Newfoundland, including the St. Lawrence-Great Lakes and upper Mississippi River basins from Quebec to northeastern Nebraska, covering provinces in Canada (Manitoba, New Brunswick, Newfoundland, Nova Scotia, Ontario, Prince Edward Island, Quebec) and numerous U.S. states (Connecticut, Delaware, Georgia, Illinois, Indiana, Iowa, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Nebraska, New Hampshire, New Jersey, New York, North Carolina, North Dakota, Ohio, Pennsylvania, Rhode Island, South Carolina, South Dakota, Vermont, Virginia, West Virginia, Wisconsin).[1][2] Ecologically, banded killifish are benthopelagic and non-migratory, forming schools a few inches below the surface in temperate waters (10–25°C), where they primarily feed on small invertebrates such as crustaceans, mollusks, and worms.[1][2] Reproduction occurs from late spring through mid-summer (June to August), with adhesive eggs laid in dense vegetation in multiple clutches per female; eggs hatch in 11–12 days, and fish reach sexual maturity by age two in some populations, though males may guard spawning sites briefly before the eggs are abandoned.[1][2][3] Globally secure (G5 status) with an estimated abundance exceeding one million individuals and stable short-term trends, the species faces no major widespread threats, though Newfoundland populations are designated as special concern due to their peripheral range position and potential unique genetic adaptations.[2][1]Taxonomy and nomenclature
Taxonomic classification
The banded killifish is classified under the binomial name Fundulus diaphanus (Lesueur, 1817), originally described from specimens collected from Saratoga Lake, New York, and Pipe Creek, Maryland.[1][4] Its full taxonomic hierarchy is as follows:| Rank | Classification |
|---|---|
| Kingdom | Animalia |
| Phylum | Chordata |
| Class | Actinopterygii |
| Order | Cyprinodontiformes |
| Family | Fundulidae |
| Genus | Fundulus |
| Species | Fundulus diaphanus |