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🌊 Marine Least Concern 🐠 Aquarium 🌡️ Tropical

Hawaiian ruby cardinalfish

Apogon erythrinus Snyder, 1904
Max Length
4 cm
Max Weight
-
Lifespan
-
Trophic Level
3.8
Depth
1–48 m
Climate
Tropical
Resilience
High
Vulnerability
10.00/100
Typical Length
-
Depth Zone
reef

📖 Overview

Found in shallow water and observed to be active only at night, near the bottom, and never far from its shelter . Benthopelagic .

Scientific Name
Apogon erythrinus
Authority
Snyder, 1904
Habitat
Marine
Climate
Tropical
Body Shape
Short and / or deep
IUCN Status
LC
Max Length
4 cm
Depth Range
1–48 m
Trophic Level
3.8
Resilience
High
Vulnerability
10.00/100
Salinity
30–40 ppt

🔬 Taxonomy

Kingdom
Animalia
Phylum
Chordata
Class
Teleostei
Teleostei
Order
Apogoniformes
Apogoniformes
Family
Apogonidae
Apogonidae
Genus
Apogon
Apogon
Species
Hawaiian ruby cardinalfish
Apogon erythrinus

🐟 Physical Description

Dorsal spines (total): 7; Dorsal soft rays (total): 8 - 9; Anal spines: 2; Anal soft rays: 8. Differs from other members of the A. erythrinus complex by having the following characteristics: from all others by having a much longer second dorsal fin spine, reaching to at least the base of third ray of second dorsal fin when depressed (spine in other species do not reach third ray); from A. indicus by having 14 pectoral fin rays (versus 13, rarely 12 or 14), and by lacking pigment on the dorsal surface of the caudal peduncle (present in A. indicus); from A. marquesensis by lacking scattered chromatophores on sides of caudal peduncle that extend anteriorly as a band from caudal fin base to vertical from ends of dorsal and anal fin rays (pigment extends forward as a band in A. marquesensis); from A. susanae by having pigment present on scale edges at front of second dorsal fin and sometimes along its base and scattered chromatophores on caudal fin base (absent in A. susanae) .: short and / or deep; Cross section: compressed.

🌀 Behaviour

Behavioural data for Hawaiian ruby cardinalfish is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

👄 Mouth Brooder

Mouthbrooders . Distinct pairing during courtship and spawning .

🌍 Habitat & Distribution

Marine; reef-associated; depth range 1 - 48 m . Tropical Central Pacific: known only from the Hawaiian Islands and Johnston Island.

🌿 Ecology

Zone Preferences
🌊 Marine 🪸 Reef Associated
Trophic Level
3.8±0.59

📐 Morphometrics

Length–Weight Relationship: W = 0.01479 × L3.06 (TL)
Max TL
4cm
Dorsal Spines
7
Dorsal Rays
9
Anal Spines
2
Anal Rays
8

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2021

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
10.00/100
Low vulnerability
Trophic Level
3.8
Predator
Body Shape
Short and / or deep
Climate Zone
Tropical
Described By
Snyder, 1904

🌐 Names & Taxonomy

Language Common Names
🇬🇧English Cryptic Cardinalfish · Hawaiian Ruby Cardinalfish · Ruby Cardinalfish
🌍CES parmovec rubínový
🇵🇹Portuguese Cardeal-rubi-havaiano
🇨🇳Chinese 大目側仔 · 大面側仔 · 粉紅天竺鯛

🦠 Common Diseases

The following diseases are known to affect Hawaiian ruby cardinalfish.

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 7 records indexed .

Occurrence density from GBIF View GBIF records ↗

👥 Community & Contribute

Aquareap Community Observations
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