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🌊 Marine Least Concern 🌡️ Tropical

Island major

Stegastes arcifrons Heller & Snodgrass, 1903
Max Length
13 cm
Max Weight
-
Lifespan
27 yrs
Trophic Level
3
Depth
1–20 m
Climate
Tropical
Resilience
Low
Vulnerability
19.00/100
Typical Length
-
Depth Zone
reef

📖 Overview

Adults inhabit coral and rocky reefs . Omnivorous . Adults are territorial and aggressive, vigorously driving off other fishes and certain invertebrates from their feeding and reproductive territories. They graze on algae and invertebrates including tubeworms, small crustaceans, and the tentacles of anemones . Oviparous, distinct pairing during breeding . Eggs are demersal and adhere to the substrate . Males guard and aerate the eggs .

Scientific Name
Stegastes arcifrons
Authority
Heller & Snodgrass, 1903
Habitat
Marine
Climate
Tropical
Body Shape
Short and / or deep
IUCN Status
LC
Max Length
13 cm
Lifespan
27 years
Depth Range
1–20 m
Latitude
2°S – 9°N
Trophic Level
3
Resilience
Low
Vulnerability
19.00/100
Migration
Non-migratory
Salinity
30–40 ppt

🐟 Physical Description

Dorsal spines (total): 12; Dorsal soft rays (total): 15 - 16; Anal spines: 2; Anal soft rays: 12 - 13. Exhibits geographic color variations.: short and / or deep; Cross section: compressed.

🌀 Behaviour

Behavioural data for Island major is currently being reviewed.

🦐 Diet

Diet information for Island major is currently being compiled.

🥚 Reproduction

🐣 Oviparous
Spawn Location
Demersal

Oviparous, distinct pairing during breeding . Eggs are demersal and adhere to the substrate . Males guard and aerate the eggs .

🌍 Habitat & Distribution

Marine; reef-associated; non-migratory; depth range 1 - 20 m . Tropical; 9°N - 2°S, 92°W - 77°W

🌿 Ecology

Zone Preferences
🌊 Marine 🪸 Reef Associated
Migration
Non-migratory
Trophic Level
3±0.39

📐 Morphometrics

Length–Weight Relationship: W = 0.02042 × L2.98 (TL)
Max TL
13cm
Dorsal Spines
12
Dorsal Rays
16
Anal Spines
2
Anal Rays
13

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2007

📊 Population Risk & Fisheries

Population Resilience
Low
Minimum doubling time
Fishing Vulnerability
19.00/100
Low vulnerability
Trophic Level
3
Predator
Body Shape
Short and / or deep
Climate Zone
Tropical
Latitude Range
9°N – 2°S
Described By
Heller & Snodgrass, 1903

🌐 Names & Taxonomy

Language Common Names
🇬🇧English Galapagos Yellowtail Damselfish · Galapagos gregory · Island major
🏳️Catalan Damisel·la de Costa Rica
🇫🇷French Chauffet des îles
🇮🇹Italian Damigella coda gialla delle Galápagos
🇵🇹Portuguese Donzela-de-cauda-amarela-de-Galápagos
🇪🇸Spanish Chopita de las Galápagos · Damisela de rabo amarillo · Jaqueta de las islas · Jaqueto amarillo

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 11 records indexed .

Occurrence density from GBIF View GBIF records ↗

👥 Community & Contribute

Aquareap Community Observations
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