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🌊 Marine Least Concern ⚡ Reports of ciguatera poisoning 🌡️ Tropical

Jack-knifefish

Eques lanceolatus Linnaeus, 1758
Max Length
25 cm
Max Weight
-
Lifespan
-
Trophic Level
3.4
Depth
10–60 m
Climate
Tropical
Resilience
High
Vulnerability
23.00/100
Typical Length
15 cm
Depth Zone
reef

📖 Overview

Inhabits bays and sounds; also deep coral reefs . Juveniles sometimes inshore . Easily approached . Has been reared in captivity . Feeds mainly on small shrimps and crabs, but also on polychaete worms and gastropod mollusks .

Scientific Name
Eques lanceolatus
Authority
Linnaeus, 1758
Habitat
Marine
Climate
Tropical
Body Shape
Fusiform / normal
IUCN Status
LC
Max Length
25 cm
Depth Range
10–60 m
Latitude
34°S – 37°N
Trophic Level
3.4
Resilience
High
Vulnerability
23.00/100
Salinity
30–40 ppt

🔬 Taxonomy

Genus
Eques
Eques
Species
Jack-knifefish
Eques lanceolatus

🐟 Physical Description

Dorsal spines (total): 13; Dorsal soft rays (total): 47 - 55; Anal spines: 2; Anal soft rays: 16. Very high first dorsal fin with a short base . Gray with three white-edged dark brown to black bands, the first running vertically through eye, the second from nape across operculum and chest to front of pelvic fins, and the last beginning on first dorsal fin and running to end of caudal fin . Third and widest band from tip of high dorsal fin, curving along length of body to tip of tail .: fusiform / normal.

🌀 Behaviour

Behavioural data for Jack-knifefish is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

🐣 Oviparous

Oviparous .

🌍 Habitat & Distribution

Marine; reef-associated; depth range 10 - 60 m . Tropical; 37°N - 34°S, 98°W - 33°W North Carolina, USA to Rio de Janeiro, Brazil (Ref.

🌿 Ecology

Zone Preferences
🌊 Marine 🪸 Reef Associated
Trophic Level
3.4±0.4
Food Items

small shrimps and crabs, but also on polychaete worms and gastropod mollusks (Ref

📐 Morphometrics

Length–Weight Relationship: W = 0.00724 × L3.19 (TL)
Max TL
25cm
Dorsal Spines
13
Dorsal Rays
51
Anal Spines
2
Anal Rays
16

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2019

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
23.00/100
Low vulnerability
Trophic Level
3.4
Predator
Body Shape
Fusiform / normal
Climate Zone
Tropical
Latitude Range
37°N – 34°S
Described By
Linnaeus, 1758

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