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🌊 Marine Data Deficient 🌡️ Temperate

Smooth handfish

Sympterichthys unipennis Cuvier, 1817
Max Length
4.4 cm
Max Weight
-
Lifespan
-
Trophic Level
3.4
Depth
-
Climate
Temperate
Resilience
-
Vulnerability
10.00/100
Typical Length
-
Depth Zone
demersal

📖 Overview

Smooth handfish (Sympterichthys unipennis), first described by Cuvier, 1817 is a tiny fish. Adults typically reach 4.40 cm in maximum length. It inhabits marine coastal and open-ocean environments. It occurs in Temperate waters. It feeds on a mix of small fish and invertebrates as a mid-level predator. On the IUCN Red List, it is classified as Data Deficient.

Scientific Name
Sympterichthys unipennis
Authority
Cuvier, 1817
Habitat
Marine
Climate
Temperate
Body Shape
Elongated
IUCN Status
DD
Max Length
4.4 cm
Trophic Level
3.4
Vulnerability
10.00/100
Salinity
30–40 ppt

🔬 Taxonomy

Genus
Sympterichthys
Sympterichthys
Species
Smooth handfish
Sympterichthys unipennis

🐟 Physical Description

Dorsal soft rays (total): 19; Anal soft rays: 9. This species is distinct with a combination of the following characters: minute esca, as a simple filament (possibly damaged); illicium with thick base, thin distally, no dermal spinules, length about 18% SL, 2.7 times in head length; close-set, embedded, nonimbricate, spiny scales cover the entire body; scale bases variable in shape, dendritic to narrowly thallate, with long unicuspid or bifurcate spinules (except for those closely associated with pores of the acoustico-lateralis system); adpressed spinules, posteriorly directed, originating from posterior region of scale base, apical spines moderately divergent; second dorsal-fin rays 17, fin base 64% SL; length of second dorsal-fin spine 1.3 times length of longest ray of second dorsal fin; anal-fin rays 9; pectoral-fin rays 9; fresh coloration unknown, pale in preservative with darker markings on first dorsal fin and membranes of pectoral, pelvic and caudal fins .: elongated.

🌀 Behaviour

Behavioural data for Smooth handfish 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; demersal. Temperate Southwest Pacific: Endemic to Tasmania, Australia.

🌿 Ecology

Zone Preferences
🌊 Marine ⬇️ Benthic
Trophic Level
3.4±0.4

📐 Morphometrics

Length–Weight Relationship: W = 0.00437 × L3.12 (TL)
Max TL
4.4cm
Dorsal Rays
19
Anal Rays
9

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Data Deficient
Assessment Date
2021

📊 Population Risk & Fisheries

Fishing Vulnerability
10.00/100
Low vulnerability
Trophic Level
3.4
Predator
Body Shape
Elongated
Climate Zone
Temperate
Described By
Cuvier, 1817

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