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🌊 Marine Least Concern 🌡️ Tropical

Blue flounder

Crossorhombus azureus Alcock, 1889
Max Length
18 cm
Max Weight
-
Lifespan
-
Trophic Level
3.5
Depth
13–60 m
Climate
Tropical
Resilience
Medium
Vulnerability
34.00/100
Typical Length
-
Depth Zone
demersal

📖 Overview

Lives on mud bottoms and feeds on bottom-living animals . Sexually dimorphic characters develop at about 6 cm SL .

Scientific Name
Crossorhombus azureus
Authority
Alcock, 1889
Habitat
Marine
Climate
Tropical
Body Shape
Short and / or deep
IUCN Status
LC
Max Length
18 cm
Depth Range
13–60 m
Trophic Level
3.5
Resilience
Medium
Vulnerability
34.00/100
Salinity
30–40 ppt

🔬 Taxonomy

🐟 Physical Description

Dorsal soft rays (total): 84 - 92; Anal soft rays: 63 - 74. Ground colour on eyed side brownish grey, with darker spots and blotches. Fins paler than body, dorsal and anal fins with small dark spots, caudal fin with 2 distinct dark bands. Males with small dark spots in anterior part of interorbital region. Blind side whitish in females. Males with distinct bluish black pyriform colour pattern on blind side. Body ovoid, its depth 1.7 to 2 times in SL. Head small, snout shorter than eye, profile steep anterior to interorbital area. Head length 3.3 to 4.5 times in SL. Interorbital region broad and concave, wider in males than females in specimens greater than about 6 cm SL. Males with a rostral spine and 1 to 3 low bony bumps around orbits. Both eyes on left side of head, front margin of upper eye slightly behind front margin of lower eye. Both eyes in males larger than about 6 cm SL with a flap on posterior area. Mouth small, reaching to or slightly beyond anterior margin of lower eye, length of upper jaw 3.1 to 4.3 times in head length. Teeth in upper jaw biserial, teeth of outer row more widely spaced than teeth of inner row; teeth in lower jaw uniserial. Gill rakers short and pointed. Scales on eyed side with long ctenii. Pectoral fin on eyed side with 11 to 14 rays, its length 1.3 to 1.6 times in head length in both sexes. Pectoral fin on blind side with 9 to 12 rays (Ref 42535).: short and / or deep.

🌀 Behaviour

Behavioural data for Blue flounder is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

🐣 Oviparous 📦 Batch Spawner
Spawning Season
spring-summer
Spawn Location
Pelagic
Fertilization
External

🌍 Habitat & Distribution

Marine; demersal; depth range 13 - 60 m . Tropical West Pacific: Bay of Bengal, northwestern Australia, South China Sea, China, Taiwan, Japan, Viet Nam, and Aru Islands, Indonesia.

🌿 Ecology

Zone Preferences
🌊 Marine ⬇️ Benthic
Trophic Level
3.5±0.37
Food Items

bottom-living animals (Ref

📐 Morphometrics

Length–Weight Relationship: W = 0.00912 × L3.04 (TL)
Max TL
18cm
Dorsal Rays
88
Anal Rays
69

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2019

📊 Population Risk & Fisheries

Population Resilience
Medium
Minimum doubling time
Fishing Vulnerability
34.00/100
Low vulnerability
Trophic Level
3.5
Predator
Body Shape
Short and / or deep
Climate Zone
Tropical
Described By
Alcock, 1889

🌐 Names & Taxonomy

Language Common Names
🇬🇧English Bluespotted Flounder · Chain-mail Flounder · Chain-mail Wide-eyed Flounder
🇯🇵Japanese Kanekodarumagarei · カネコダルマガレイ
🇨🇳Chinese 半邊魚 · 扁魚 · 比目魚 · 皇帝魚 · 青纓鮃

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 3 records indexed .

Occurrence density from GBIF View GBIF records ↗

👥 Community & Contribute

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