About Etheostoma chlorosomum (Hay, 1881)
Bluntnose darters (scientific name Etheostoma chlorosomum, Hay, 1881) reach a maximum length of 2 inches (5.1 cm). This species has a characteristic very round, blunt snout. It is light yellow or olive on its dorsal side, marked with dark brown or black spots or uneven dense lines. Its belly is white, and W-shaped marks appear on its flanks. A continuous black bar crosses the area in front of the eyes, wrapping around the snout, and this barring extends slightly onto the upper lip. The dorsal and caudal fins have light brown pigmented bands, while all other fins are clear. The species has one anal spine. The opercle, cheek, and prepectoral area are covered in scales; the breast may be fully or partially scaled, and scales can be embedded. The belly is either fully scaled, or scaled on the posterior portion and unscaled on the anterior portion. Bluntnose darters have an incomplete lateral line. When breeding, males develop darker, dusky breeding coloration from unevenly distributed melanophores across their fins and the underside of their body. Breeding tubercles grow on the pelvic and anal fins of breeding individuals, and females develop a large, spatulate genital papilla. This species is native to North America, where it occurs from the San Antonio Bay drainage in Texas east to Mississippi, Alabama and Indiana, and north to Minnesota. It was formerly found in the Lake Michigan drainage area. In Louisiana, it is one of the most widely distributed darter species, found in all river drainages, but absent from the southernmost estuarine environments. Bluntnose darters live in swamps, floodplain lakes, sloughs, and low-gradient creeks, often over substrates made of mud, clay or detritus. They can also be found in large rivers, where they most often occupy backwaters. The typical lifespan of the bluntnose darter is around three years. Spawning timing varies across the species' range: in Texas, spawning occurs from early January to late March; in Kansas, spawning occurs in April; and in Louisiana, spawning occurs in March and April. Males court females with displays that involve posing while quivering with their fins held upright. The female selects the spawning site, most commonly choosing algae, dead leaves, or a small twig. Males mount females to fertilize eggs, fertilizing only 1 to 3 eggs per mating attempt. Larval development of the bluntnose darter has not been described to date.
