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🌊 Marine Least Concern 🌡️ Tropical

Flagtail swellshark

Cephaloscyllium signourum Last, Séret & White, 2008
Max Length
74.1 cm
Max Weight
-
Lifespan
-
Trophic Level
4.1
Depth
480–700 m
Climate
Tropical
Resilience
Low
Vulnerability
56.00/100
Typical Length
-
Depth Zone
-

📖 Overview

Flagtail swellshark (Cephaloscyllium signourum) is a ray-finned fish of the family Scyliorhinidae. It inhabits marine (saltwater) waters. This species can reach a maximum total length of 74.1 cm. It occurs at depths between 480 and 700 metres. With a trophic level of 4.1, it is a mid-level predator. It is assessed as Least Concern on the IUCN Red List.

Scientific Name
Cephaloscyllium signourum
Authority
Last, Séret & White, 2008
Habitat
Marine
Climate
Tropical
Body Shape
Elongated
IUCN Status
LC
Max Length
74.1 cm
Depth Range
480–700 m
Trophic Level
4.1
Resilience
Low
Vulnerability
56.00/100
Salinity
30–40 ppt

🐟 Physical Description

This medium-sized species has the following set of characters which was based on the holotype: head 7.5% TL in height, trunk 16.3% TL in width; origin of first dorsal-fin is over the anterior pelvic-fin base; prenarial 3.6% TL in length; preorbital snout length is 2.0 times prenarial length, 3.0 in prepectoral length, 6.6 in prepelvic length; snout-vent length long, 51.7% TL; nostril width 2.7% TL; eye-spiracle space narrow, 0.5% TL; pectoral fin medium-sized, its height 12.8% TL, posterior margin 11.9% TL; anal fin tall, 4.0% TL; anal-caudal space is 5.0% TL; precaudal length is 76% TL; interdorsal space is 6.6% TL; teeth with 3 well-developed cusps near symphysis of upper jaw; mostly unicuspidate flank denticles; back without the greatly enlarged denticles; adult clasper unknown; vertebral centra 115-116; tooth count high, 84 teeth in upper jaws, 97 in lower jaws; color of upper half of body medium brown, with a variegated pattern that is not clearly demarcated from the ventral surface; dark saddles (10) evident on body and tail; dorsal fins are pale variegated; dark blotch absent over gills; marking on posterior margin of terminal lobe of caudal fin dark, anteriorly directed, V-shaped; upper surface of pectoral-fin with a dark brown central blotch; centered over ventral origin of caudal fin is a well-developed saddle; ventral surface is uniformly greyish or white in color; juveniles are pale with dark transverse markings appearing as narrow bars and hollow saddles; markings between spiracles not separated into two unconnected pseudo-ocelli .: elongated.

🌀 Behaviour

Behavioural data for Flagtail swellshark is currently being reviewed.

🦐 Diet

small fish
crustaceans
cephalopods

🥚 Reproduction

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

🌍 Habitat & Distribution

Marine; benthopelagic; depth range 480 - 700 m . Tropical

🌿 Ecology

Zone Preferences
🌊 Marine
Trophic Level
4.1±0.5

📐 Morphometrics

Length–Weight Relationship: W = 0.00269 × L3.21 (TL)
Max TL
74.1cm

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2025

📊 Population Risk & Fisheries

Population Resilience
Low
Minimum doubling time
Fishing Vulnerability
56.00/100
High vulnerability
Trophic Level
4.1
Apex / Top predator
Body Shape
Elongated
Climate Zone
Tropical
Described By
Last, Séret & White, 2008

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