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💧 Freshwater Least Concern 🐠 Aquarium 🌡️ Temperate

Speckled dace

Rhinichthys osculus Girard, 1856
Max Length
11 cm
Max Weight
-
Lifespan
-
Trophic Level
2.9
Depth
-
Climate
Temperate
Resilience
High
Vulnerability
25.00/100
Typical Length
6.3 cm
Depth Zone
demersal

📖 Overview

Adults occur in rocky riffles, runs and pools of headwaters, creeks and small to medium rivers; rarely in lakes . Migratory behaviour is undetermined .

Scientific Name
Rhinichthys osculus
Authority
Girard, 1856
Habitat
Freshwater
Climate
Temperate
Body Shape
Elongated
IUCN Status
LC
Max Length
11 cm
Trophic Level
2.9
Resilience
High
Vulnerability
25.00/100
Water Temp
9–11 °C
Salinity
0–0.5 ppt

🔬 Taxonomy

🐟 Physical Description

Dorsal spines (total): 0; Dorsal soft rays (total): 8 - 9; Anal spines: 0; Anal soft rays: 6 - 7; Vertebrae: 37 - 38. Body elongate, greatest depth in front of dorsal fin. Head bluntly triangular, a small but distinct hump present behind the head. Mouth inferior, sucker-like, lower jaw with fleshy lip. Overall coloration gray or gray-brown with scattered and vague darker flecks, usually above midline of sides; lower sides and belly somewhat yellowish or creamy white. A faint lateral band present.: elongated; Cross section: compressed.

🌀 Behaviour

Behavioural data for Speckled dace is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

🐣 Oviparous
Spawning Season
spring
Spawn Location
Substrate
Fertilization
External

🌍 Habitat & Distribution

Freshwater; demersal; pH range: 6.8 - 7.8; dH range: 5 - 25. Temperate; 9°C - 11°C ; 49°N - 31°N North America: western drainages (Pacific and endorheic) from Columbia River in British Columbia, Canada to Colorado River in Arizona and New Mexico, USA and south into Sonora, Mexico.

🌿 Ecology

Zone Preferences
💧 Freshwater ⬇️ Benthic
Trophic Level
2.9±0.36

📐 Morphometrics

Length–Weight Relationship: W = 0.00525 × L3.1 (TL)
Max TL
11cm
Dorsal Rays
9
Anal Rays
7
Vertebrae
38

🌡️ Water Parameters & Tolerance

Temperature Range
9–11°C
pH Range
6.8–7.8
Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2018

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
25.00/100
Low vulnerability
Trophic Level
2.9
Omnivore / Planktivore
Body Shape
Elongated
Climate Zone
Temperate
Described By
Girard, 1856

🌐 Names & Taxonomy

Language Common Names
🇬🇧English speckled dac · Speckled Dace
🇫🇷French naseux moucheté · nasuex moucheté
🇪🇸Spanish carpita pinta

Scientific Synonyms

Scientific Name Author Year Status
Agosia klamathensis Evermann & Meek 1898 Synonym
Agosia novemradiata Cope 1883 Synonym
Agosia oscula Girard 1856 Synonym
Apocope carringtonii Cope 1872 Synonym
Apocope couesii Yarrow 1875 Synonym
Apocope oscula Girard 1856 Synonym
Apocope oscula carringtonii Cope 1872 Synonym
Apocope oscula nubila Forbes 1878 Synonym
Apocope oscula thermalis Hubbs & Kühne 1937 Synonym
Apocope vulnerata Cope 1872 Synonym
Argyreus notabilis Girard 1856 Synonym
Argyreus nubilus Girard 1856 Synonym
Argyreus osculus Girard 1856 Synonym
Ceratichthys squamilentus Cope 1871 Synonym
Rhinichthys henshavii Cope 1874 Synonym
Rhinichthys lariversi Lugaski 1972 Synonym
Rhinichthys nevadensis Gilbert 1893 Synonym
Rhinichthys nubilus Girard 1856 Synonym
Rhinichthys osculus carringtonii Cope 1872 Synonym
Rhinichthys osculus klamathensis Evermann & Meek 1898 Synonym
Rhinichthys osculus lariversi Lugaski 1972 Synonym
Rhinichthys osculus lethoporus Hubbs & Miller 1972 Synonym
Rhinichthys osculus moapae Williams 1978 Synonym
Rhinichthys osculus nevadensis Gilbert 1893 Synonym
Rhinichthys osculus nubilus Girard 1856 Synonym
Rhinichthys osculus oligoporus Hubbs & Miller 1972 Synonym
Rhinichthys osculus reliquus Hubbs & Miller 1972 Synonym
Rhinichthys osculus thermalis Hubbs & Kühne 1937 Synonym
Rhinichthys osculus velifer Gilbert 1893 Synonym
Rhinichthys velifer Gilbert 1893 Synonym

… and 1 more synonyms

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 45 records indexed .

Occurrence density from GBIF View GBIF records ↗

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