Bluntnose darters start out with an embryonic period, which begins at fertilization. They advance to a larval period when they are able to capture food. Once the organ systems are formed, they enter the juvenile period. They are finally classified as adults when they are able to reproduce (i.e., when gonads become mature).
Bluntnose darters are pale yellow with a translucent look to them. They have blunt noses and five to six small dorsal saddles. They are also identified by having several small brown “W”’s and “X”’s spread randomly throughout the side of the body. Dorsal and caudal fins are speckled with brown . The suborbital bar is usually present as well as the preorbital bar. The preorbital bar is a distinguishing factor in determining bluntnose darters from Johnny darters, Etheostoma nigrum which are similar in appearance. The preorbital bar connects in the bluntnose darter in contrast to the johnny darter where it does not. The anal fin has one spine and 7-9 soft rays (Etnier and Starnes 1993). The dorsal fin has 8-10 spines and 10-11 soft rays and the caudal fin consists of 13-17 rays. The lateral line is incomplete with a lateral line count of 51-60. The species name E. chlorosoma is broken down chloro = green, soma = body. This name can be misleading because green may only be seen faintly on good specimens. Bluntnose darters can reach a length of 38 to 46 mm during adult stages of life. Males and females appear similar outside of the breeding season, but are sexually dichromatic during the breeding season.
Range length: 38 to 46 mm.
Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry
Sexual Dimorphism: sexes alike; sexes colored or patterned differently
Bluntnose darters lifespan may be cut short by siltation from agricultural runoff. Their habitat in shallow water can also limit their life when creeks dry up during periods of drought. No exact numbers were found on bluntnose darters. However in the closely related Johnny darters, Etheostoma nigrum, suggested lifespan is 3 years.
Bluntnose darters are typically found in sandy, slow running, shallow water. They also can be found occupying areas with scattered debris. Substrates that are somewhat firm also provide a good habitat for bluntnose darters.
Habitat Regions: freshwater
Bluntnose darters, Etheostoma chlorosoma, are primarily found in the Mississippi River drainage basin. They may also be found in the Mobile Bay drainage and San Antonio River drainage basin.
Biogeographic Regions: nearctic (Native )
Bluntnose darters are invertivores. Bluntnose darters feed on minute freshwater organisms such as chironomid, blackfly larvae, Cyclops species, and Daphnia species.
Animal Foods: insects; aquatic crustaceans
Primary Diet: carnivore (Insectivore , Eats non-insect arthropods)
No specific information was found on bluntnose darters. However darters may have an commensal relationship with freshwater mussels. Commensal relationships occur when one species benefits from the relationship while the other is not affected. They may be integral in the reproductive cycle by having glochidia attach to their gills.
There is no direct benefit bluntnose darters have toward humans.
Bluntnose darters have no adverse affects on humans.
Bluntnose darters are threatened in several states along the Mississippi River and adjacent drainages. According to NatureServe Explorer ( http://www.natureserve.org/explorer/), bluntnose darters in Kansas are presumed extirpated, in Wisconsin they are critically imperiled, in Kansas they are imperiled, in Indiana they are vulnerable. Bluntnose darter populations are apparently secure in Kentucky, Illinois, Minnesota, Missouri, Arkansas, Oklahoma, Texas, Tennessee, Alabama, Mississippi, and Louisiana. Their decline could be caused by siltation resulting from agricultural runoff and creeks drying up during periods of drought.
US Federal List: no special status
CITES: no special status
Darters communicate by coloration during breeding seasons. This coloration is used to attract the opposite sex.
Communication Channels: visual
Perception Channels: visual ; tactile ; chemical
Bluntnose darters are small and are likely to be prey for larger species of fish. During the non-breeding season they are light tan with dark brown blotches. This color pattern may provide camouflage from potential predators against the bottom of creeks and streams.
Known Predators:
Anti-predator Adaptations: cryptic
Bluntnose darters are polygynandrous, where females go from one male to the other to maximize their reproductive success. They show dichromatism during the breeding season. Dichromatism is when the species changes color when it is time to attract a mate. During the breeding season males become darker on their belly, dorsal fin, and pelvic fins. They also develop sharp tubercles on the soft rays of their anal and pelvic fins. These breeding tubercles are tiny hard bumps of keratin. While the male courts the female with these rituals, the female usually chooses where to lay the eggs.
Mating System: polygynandrous (promiscuous)
Bluntnose darters are nest spawners. Females select suitable places where the eggs are deposited and fertilized. They use plants or plant debris as suitable places to lay their eggs. They lay their eggs in April or May when the water temperature is suitable for their reproduction success. They usually attach one to three eggs per spawning act. Territoriality is seen in bluntnose darters because they spend time in one specific place guarding the embryo or defending the area. They also show elaborate courtship behaviors. This is shown by the males during breeding season with their elaborate coloration. Females usually produce 230-1000 eggs per reproductive effort. They usually reach maturity at one year of age.
Breeding interval: Bluntnose darters breed seasonally each year.
Breeding season: They lay their eggs in April or May when the water temperature is suitable for their reproduction success
Range number of offspring: 230 to 1000.
Average age at sexual or reproductive maturity (female): 1 years.
Average age at sexual or reproductive maturity (male): 1 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (External ); oviparous
Parental care is provided by the male. This could be due to the greater parental investment the female has in gonadal development when compared to the smaller investment the males make (i.e., sperm vs. ova). Females usually abandon eggs to search for more breeding opportunities. Females have been known to spawn many times during the reproductive season.
Parental Investment: pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Male)
Etheostoma chlorosomum és una espècie de peix pertanyent a la família dels pèrcids.[5] Es troba a Amèrica del Nord: la conca del riu Mississippí des del sud de Minnesota fins a Louisiana. També és present des de la badia de Mobile (Alabama) fins a la conca del riu San Antonio (Texas).[6] Temps enrere també ocupava la conca del llac Michigan a Illinois.[7][8][9][10][11] Pot arribar a fer 6 cm de llargària màxima. És de color groc clar amb les aletes dorsal i caudal clapejades de marró. L'aleta anal té una espina i 7-9 radis tous. L'aleta dorsal té 8-10 espines i 10-11 radis tous. L'aleta caudal té 13-17 radis. La línia lateral incompleta.[7][12][13] És inofensiu per als humans.[7]
És un peix d'aigua dolça, bentopelàgic i de clima subtropical (44°N-29°N), el qual viu a llacs, pantans, rierols, aigües estancades i rius petits i mitjans de fons fangós (de vegades, també, de sorra).[14][7] Els adults mengen Hydropsychidae, Dytiscidae i larves de mosquit.[15] Les femelles, a l'abril o el maig i sempre que la temperatura sigui l'adequada, seleccionen els indrets on pondran els ous (entre 230 i 1.000), adherits al substrat i deixats sota la protecció del mascle. Les femelles generalment abandonen els ous a la recerca d'altres mascles per tornar a reproduir-se diverses vegades durant l'època de fresa.[16][13] És un peix petit i, per tant, una presa més que probable per a altres espècies més grosses de peixos. Durant la temporada no reproductiva és de color canyella clar amb taques marrons, la qual cosa li proporciona una certa protecció en camuflar-se contra el fons dels rierols i rius.[13]
Etheostoma chlorosomum és una espècie de peix pertanyent a la família dels pèrcids. Es troba a Amèrica del Nord: la conca del riu Mississippí des del sud de Minnesota fins a Louisiana. També és present des de la badia de Mobile (Alabama) fins a la conca del riu San Antonio (Texas). Temps enrere també ocupava la conca del llac Michigan a Illinois. Pot arribar a fer 6 cm de llargària màxima. És de color groc clar amb les aletes dorsal i caudal clapejades de marró. L'aleta anal té una espina i 7-9 radis tous. L'aleta dorsal té 8-10 espines i 10-11 radis tous. L'aleta caudal té 13-17 radis. La línia lateral incompleta. És inofensiu per als humans.
The bluntnose darter (Etheostoma chlorosomum) is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches.[2] It is found in eastern North America where it is found in slower moving and still waters.
The bluntnose darter was first formally described by the American Oliver Perry Hay (1846-1930) with the type locality given as the Cullasaja River at Macon County, North Carolina.[3] The generic name Etheostoma derives from Greek etheo, "to strain", and stoma, "mouth". The specific name chlorosomum is Greek for "greenish-yellow".[4]
Bluntnose darters attain a size of up to 2 inches (5.1 cm).[5] the species has a diagnostic very round, blunt snout. Its color is light yellow or olive dorsally with either dark brown or black spots or uneven dense lines. The belly is white. The flanks bear W-shaped marks .[6] The area in front of the eyes consists of continuous black bars around the snout. This barring also slightly extends onto the upper lip. The dorsal and caudal fins have some pigment in light brown bands, while the other fins are clear. There is a single anal spine. The opercle, cheek, and prepectoral area are scaled, while the breast may be fully or partially scaled. Scales may be embedded. The belly is either fully scaled or scaled posteriorly and unscaled anteriorly.[5] Bluntnose darters have an incomplete lateral line.[6]
During breeding, males take on a darker or dusky breeding coloration, induced by melanophores unevenly distributed throughout the fins, and on the underside of the body.[6] Breeding tubercles develop on the pelvic and anal fins. Females develop a large, spatulate genital papillae.[5]
The species occurs in North America from the San Antonio Bay drainage in Texas east to Mississippi, Alabama and Indiana, and north to Minnesota. It was formerly present in the Lake Michigan drainage area.[1] In Louisiana, the bluntnose darter is one of the most widely distributed darters and is found in all river drainages, but it is absent in the southernmost estuarine environments.[7] The species is found in swamps, floodplain lakes, sloughs, and low-gradient creeks, often over substrates of mud, clay or detritus. It can be found in large rivers, where it most often occupies backwaters.[8]
In specimens found in Tennessee, the bluntnose darter's diet was made up of aquatic insects such as caddisfly larvae, dytiscid beetles, and midge larvae.[6]
The lifespan of the bluntnose darter is likely about three years. Spawning occurs at different times of year throughout the range; in Texas, a spawning period from early January to late March has been observed,[6] April in Kansas, and March and April in Louisiana.[5] Males court females in displays that include of posing while quivering with upright fins. The spawning site is chosen by the female. She usually selects algae, dead leaves, or a small twig. Males mount the females for fertilization, only fertilizing 1-3 eggs per attempt.[6] Larval development of the bluntnose darter has not yet been described.[5]
The bluntnose darter (Etheostoma chlorosomum) is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is found in eastern North America where it is found in slower moving and still waters.
Etheostoma chlorosoma es una especie de peces de la familia Percidae en el orden de los Perciformes.
Los machos pueden llegar alcanzar los 6 cm de longitud total.[1]
Se encuentran en Norteamérica.
Etheostoma chlorosoma es una especie de peces de la familia Percidae en el orden de los Perciformes.
Etheostoma chlorosomum Etheostoma generoko animalia da. Arrainen barruko Percidae familian sailkatzen da.
Etheostoma chlorosomum Etheostoma generoko animalia da. Arrainen barruko Percidae familian sailkatzen da.
Etheostoma chlorosomum is een straalvinnige vissensoort uit de familie van de echte baarzen (Percidae).[1] De wetenschappelijke naam van de soort is voor het eerst geldig gepubliceerd in 1881 door Hay.
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