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🌊 Marine Least Concern 🌡️ Tropical

Yellow-black threefin

Enneapterygius gracilis Fricke, 1994
Max Length
2.8 cm
Max Weight
-
Lifespan
-
Trophic Level
3.1
Depth
0–15 m
Climate
Tropical
Resilience
High
Vulnerability
10.00/100
Typical Length
-
Depth Zone
reef

📖 Overview

Adults occur in shallow tidal pools, and seems to be associated with coralline rock and seagrass . Eggs are hemispherical and covered with numerous sticky threads that anchor them in the algae on the nesting sites . Larvae are planktonic which occur primarily in shallow, nearshore waters .

Scientific Name
Enneapterygius gracilis
Authority
Fricke, 1994
Habitat
Marine
Climate
Tropical
Body Shape
Elongated
IUCN Status
LC
Max Length
2.8 cm
Depth Range
0–15 m
Trophic Level
3.1
Resilience
High
Vulnerability
10.00/100
Migration
Non-migratory
Salinity
30–40 ppt

🔬 Taxonomy

🐟 Physical Description

Dorsal spines (total): 15; Dorsal soft rays (total): 9 - 11; Anal spines: 1; Anal soft rays: 16 - 18. This species is distinguished by the following set of characters: D2 XI or XII (modally 12); D2 9-11; A I,16-18 (7); pectoral fin-rays ii–iv (iii) + 4–6 (5) + vi–vii (vii) = 14–16 (iii + 5 + vii = 15 in holotype and 4 paratypes, iv + 4 + vii = 15 in 2 paratypes, iv + 5 + vii = 16 and ii + 6 + vi = 14 in single paratype specimen and non-type specimen); pored lateral-line scales 12 or 13; notched lateral-line scales 19-22; scales rows in longitudinal series 31-34; scales above 1st pored lateral-line scale 2 or 2½; scales below 1st notched lateral-line scale 3 or 3½ ; circumpeduncular scales 8; mandibular pores 3-4 + 1-2 + 3-4 (usually 3 + 2 + 3; 3 + 2 + 3 in holotype, 6 paratypes, and a non-type specimen, 3 + 1 + 3 and 4 + 2 + 4 in single paratype only); head relatively long, its length 29.2-32.5% (mean 30.6%) of SL; upper jaw length 9.2-11.7% (11.0%) of SL; first spine of first dorsal fin slightly longer than that of second dorsal fin, its length 10.8-17.9% (13.9%) of SL; anterior nostril tentacle unbranched; orbital tentacle circular, the edge slightly pointed, its length slightly less than or subequal to pupil diameter, Colouration: body generally yellowish or brownish with 6 or 7 bands, darker around lateral line; brownish blotches on each of pectoral-fin ray, forming 3 or 4 narrow bands; anal fin with 7-9 .: elongated; Cross section: oval.

🌀 Behaviour

Behavioural data for Yellow-black threefin 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; reef-associated; non-migratory; depth range 0 - 15 m . Tropical West Pacific: Endemic to northern Australia.

🌿 Ecology

Zone Preferences
🌊 Marine 🪸 Reef Associated
Migration
Non-migratory
Trophic Level
3.1±0.3

📐 Morphometrics

Length–Weight Relationship: W = 0.00617 × L3.03 (TL)
Max TL
2.8cm
Dorsal Spines
15
Dorsal Rays
10
Anal Spines
1
Anal Rays
17

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2010

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
10.00/100
Low vulnerability
Trophic Level
3.1
Predator
Body Shape
Elongated
Climate Zone
Tropical
Described By
Fricke, 1994

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 1 records indexed .

Occurrence density from GBIF View GBIF records ↗

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