Eastern blacknose dace (Rhinichthys atratulus)

General data

Main name: Eastern blacknose dace
Climates: Subtropical, Temperate, Continental
Habitat: Freshwater
Native: North America
Distribution: St. Lawrence River, Hudson River, Potomac, Susquehanna River, Connecticut River, Savannah river, View all... Pee Dee river, Apalachicola

Classification

Description

Eastern blacknose dace (Rhinichthys atratulus) is a species of ray-finned fish in the genus Rhinichthys. Its name originates from the Old French word dars which is the nominative form of the word dart in reference to their swimming pattern. The western blacknose dace (Rhinichthys obtusus) formerly was considered conspecific. While morphologically the two species are not significantly different, they are allopatric. The eastern blacknose dace is found across the southeast portion of Canada and down along the United States east coast. It is dark brown to olive on its dorsal surface and silvery white below, the two shades separated by the darkly pigmented lateral line. In the breeding season, males develop darker pigmentation and an orange lateral line. Blacknose dace live in rocky streams and rivers where they feed upon small invertebrates and microscopic biological matter and provide forage for larger fish. As a fry, this fish is 5 mm long, and some of the larger eastern blacknose dace can reach slightly over 100 mm. They tend to live for two or three years and grow continuously during this period. They have a fusiform body shape and the mouth is in a subterminal position. The lateral line is darkly colored and has 56 to 70 scales from anterior to posterior. Above the lateral line coloration can vary between shades of dark brown and even olive, while below the lateral line coloration is lighter up until a white belly. Their caudal fin is forked, and their single dorsal fin has 8 fin rays and no spines. They have a pair of pectoral fins and a pair of abdominal ventral fins, as well as an anal fin with 7 rays. All fins are clear to yellow except males during spawning season acquire an orange to red tint in all fins and along the lateral line. This fish is mainly found along the southern border of Canada extending along from Manitoba to the Atlantic Ocean, south along the east coast of the United States and slightly inland to South Carolina and Georgia. Scientists hypothesize that 20,000 years ago, as the glaciers retreated, blacknose dace recolonized the region from a single refugium in modern-day Connecticut, as soon as 75 years after the ice receded. This fish tends to inhabit headwaters, creeks, and small rivers with swiftly moving water. However, fry mature in slower moving portions of the habitats like shoals and pool margins. The species as a whole prefers cool, rocky areas and uses the stones to rest under and around. They also use overhanging vegetation and undercut banks for additional refuge. In the winter, they migrate from headwater streams into rivers and can be found in deeper water under banks.

Taxonomy of Fishes

Osteichthyes - Bony fishes->
- Coelacanthi - Lobe-finned fishes->
- Teleostei - Ray-finned fishes->
  - Perciformes - Perches->
  - Cypriniformes - Carps->
    
    Cyprinidae - Carps->
    
    Gobionidae - Gudgeons->
    
    Tincidae - Tench->
    
    Cobitidae - True loaches->
    
    Acheilognathidae - Bitterling-like cyprinids->
    
    Leuciscidae - Chub family->
    
    Squalius - Chubs->
    
    Abramis - Breams->
    
    Ballerus - Blue Breams->
    
    Blicca - Silver Breams->
    
    Vimba - Vimbas->
    
    Chondrostoma - Nases->
    
    Alburnoides - Riffle minnows->
    
    Alburnus - Bleaks->
    
    Phoxinus - Eurasian minnows->
    
    Leucaspius - Moderlieschens->
    
    Leuciscus - Eurasian daces->
    
    Telestes - Souffies->
    
    Pelecus - Sabrefishes->
    
    Rutilus - Roaches->
    
    Scardinius - Rudds->
    
    Pachychilon - Macedonian Roaches->
    
    Pelasgus - Greek minnow->
    
    Achondrostoma - Achondrostoma->
    
    Ptychocheilus - Pikeminnows->
    
    Pseudaspius - Amur asp->
    
    Pseudochondrostoma - Pseudo nase->
    
    Gila - Gila chub->
    
    Luxilus - Luxilus->
    
    Semotilus - Creek chubs->
    
    Notemigonus - Golden shiners->
    
    Siphateles - Siphateles->
    
    Richardsonius - Redside shiners->
    
    Orthodon - Orthodon->
    
    Campostoma - Stonerollers->
    
    Nocomis - North American chubs->
    
    Leucos - Adriatic roaches->
    
    Sarmarutilus - Sarmarutilus->
    
    Delminichthys - Karst minnows->
    
    Phoxinellus - Adriatic naked minnows->
    
    Parachondrostoma - South-west European nase->
    
    Iberochondrostoma - Iberian nase->
    
    Petroleuciscus - Ponto-Caspian chubs->
    
    Pimephales - Bluntnose minnows->
    
    Rhinichthys - Riffle daces->
    
    Western blacknose dace (Rhinichthys obtusus)
    
    Longnose dace (Rhinichthys cataractae)
    
    Speckled dace (Rhinichthys osculus)
    
    Eastern blacknose dace (Rhinichthys atratulus)
    
    Loach minnow (Rhinichthys cobitis)
    
    Las Vegas Dace (Rhinichthys deaconi)
    
    Umpqua dace (Rhinichthys evermanni)
    
    Leopard dace (Rhinichthys falcatus)
    
    Umatilla dace (Rhinichthys umatilla)
    
    Cyprinella - Satinfin shiners->
    
    Macrhybopsis - Blacktail chubs->
    
    Platygobio - Platygobio->
    
    Chrosomus - Redbelly dace->
    
    Notropis - Eastern shiners->
    
    Erimystax - Slender chubs->
    
    Clinostomus - Redside daces->
    
    Couesius - Couesius->
    
    Mylocheilus - Mylocheilus->
    
    Acrocheilus - Acrocheilus->
    
    Acanthobrama - Acanthobrama->
    
    Agosia - Agosia->
    
    Algansea - Algansea->
    
    Anaecypris - Anaecypris->
    
    Aspiolucius - Aspiolucius->
    
    Aztecula - Aztecula->
    
    Capoetobrama - Capoetobrama->
    
    Hemitremia - Hemitremia->
    
    Codoma - Codoma->
    
    Dionda - Desert Minnows->
    
    Eremichthys - Eremichthys->
    
    Ericymba - Ericymba->
    
    Evarra - Evarra->
    
    Exoglossum - Exoglossum->
    
    Hesperoleucus - Hesperoleucus->
    
    Hybognathus - Hybognathus->
    
    Hybopsis - Hybopsis->
    
    Iberocypris - Iberocypris->
    
    Iotichthys - Iotichthys->
    
    Ladigesocypris - Ladigesocypris->
    
    Lavinia - Lavinia->
    
    Lepidomeda - Lepidomeda->
    
    Leucalburnus - Leucalburnus->
    
    Lythrurus - Lythrurus->
    
    Margariscus - Margariscus->
    
    Meda - Meda->
    
    Mirogrex - Mirogrex->
    
    Moapa - Moapa->
    
    Mylopharodon - Mylopharodon->
    
    Opsopoeodus - Opsopoeodus->
    
    Oregonichthys - Oregonichthys->
    
    Oreoleuciscus - Oreoleuciscus->
    
    Pararhinichthys - Pararhinichthys->
    
    Phenacobius - Phenacobius->
    
    Plagopterus - Plagopterus->
    
    Pogonichthys - Pogonichthys->
    
    Protochondrostoma - Protochondrostoma->
    
    Pseudophoxinus - Pseudophoxinus->
    
    Pteronotropis - Pteronotropis->
    
    Relictus - Relictus->
    
    Rhynchocypris - Rhynchocypris->
    
    Tampichthys - Tampichthys->
    
    Stypodon - Stypodon->
    
    Tropidophoxinellus - Tropidophoxinellus->
    
    Yuriria - Yuriria->
    
    Paranotropis - Paranotropis->
    
    Miniellus - Miniellus->
    
    Nemacheilidae - Stone loaches->
    
    Xenocyprididae - East Asian minnows->
    
    Catostomidae - Suckers->
    
    Leptobarbidae - Cigar barbs->
    
    Balitoridae - River loaches->
    
    Barbuccidae - Fire-eyed loaches->
    
    Botiidae - Pointface loaches->
    
    Danionidae - Danios->
    
    Ellopostomatidae - Square-head loaches->
    
    Gastromyzontidae - Hillstream loaches->
    
    Gyrinocheilidae - Algae eaters->
    
    Paedocyprididae - Tiny carps->
    
    Psilorhynchidae - Mountain carps->
    
    Serpenticobitidae - Snake loaches->
    
    Sundadanionidae - Tiny danios->
    
    Tanichthyidae - Mountain minnows->
    
    Vaillantellidae - Longfin loaches->
  - Esociformes - Pikes->
  - Salmoniformes - Salmons and Trouts->
  - Siluriformes - Catfishes->
  - Scorpaeniformes - Mail-cheeked fishes->
  - Gasterosteiformes - Sticklebacks->
  - Gadiformes - Cods->
  - Anguilliformes - Eels and morays->
  - Clupeiformes - Herrings->
  - Syngnathiformes - Pipefishes and Seahorses->
  - Gobiiformes - Gobies->
  - Mugiliformes - Mullets->
  - Carangiformes - Jacks->
  - Beloniformes - Needlefishes->
  - Labriformes - Wrasses->
  - Scombriformes - Mackerels->
  - Mulliformes - Goatfishes->
  - Pleuronectiformes - Flatfishes->
  - Aulopiformes - Grinners->
  - Blenniiformes - Blennies->
  - Cyprinodontiformes - Toothcarps->
  - Osmeriformes - Smelts->
  - Centrarchiformes - Basses and sunfishes->
  - Cichliformes - Cichlids->
  - Characiformes - Characins->
  - Osteoglossiformes - Bony tongues->
  - Elopiformes - Tarpons and tenpounders->
  - Anabantiformes - Gouramies and snakeheads->
  - Gymnotiformes - South American knifefish->
  - Istiophoriformes - Barracudas->
  - Albuliformes - Bonefishes->
  - Lepidogalaxiiformes - Salamanderfishes->
  - Lophiiformes - Anglerfishes->
  - Spariformes - Breams and porgies->
  - Trachiniformes - Weeverfishes->
  - Moroniformes - Temperate basses->
  - Acanthuriformes - Surgeonfishes->
  - Zeiformes - Dories->
  - Tetraodontiformes - Puffers and filefishes->
  - Holocentriformes - Squirrelfishes->
  - Dactylopteriformes - Flying gurnards->
  - Lampriformes - Lamprids->
  - Galaxiiformes - Southern smelts->
  - Batrachoidiformes - Toadfishes->
  - Hiodontiformes - Mooneyes->
  - Percopsiformes - Trout-perches->
  - Callionymiformes - Dragonets->
  - Atheriniformes - Silversides->
  - Notacanthiformes - Spiny eels->
  - Saccopharyngiformes - Swallowers and Gulpers->
  - Alepocephaliformes - Slickheads and tubeshoulders->
  - Gonorynchiformes - Milkfishes->
  - Argentiniformes - Marine smelts->
  - Stomiiformes - Lightfishes and dragonfishes->
  - Ateleopodiformes - Jellynose fishes->
  - Myctophiformes - Lanternfishes->
  - Stylephoriformes - Tube-eyes->
  - Polymixiiformes - Beardfishes->
  - Beryciformes - Sawbellies->
  - Trachichthyiformes - Rughies->
  - Ophidiiformes - Cusk-eels->
  - Kurtiformes - Nurseryfishes & Cardinalfishes->
  - Synbranchiformes - Swamp eels->
  - Gobiesociformes - Clingfishes->
  - Acropomatiformes - Oceanic basses->
- Cladistii - Bichirs->
- Dipneusti - Lungfishes->
- Chondrostei - Sturgeons->
- Holostei - Gars and Bowfins->
Chondrichthyes - Cartilaginous fishes->
Agnatha - Jawless fishes->