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🌊 Marine Least Concern 🌡️ Deep-water

California headlightfish

Diaphus theta Eigenmann & Eigenmann, 1890
Max Length
11.4 cm
Max Weight
-
Lifespan
-
Trophic Level
3.2
Depth
10–3400 m
Climate
Deep-water
Resilience
High
Vulnerability
25.00/100
Typical Length
-
Depth Zone
deep-water

📖 Overview

Epipelagic to mesopelagic . Feed at night or in the morning , on euphausiids, copepods, and amphipods . Oviparous, with planktonic eggs and larvae . Lipid content is 15.8 % in fresh body weight while wax ester is present in trace amounts . Minimum depth reported from Ref. 28981.

Scientific Name
Diaphus theta
Authority
Eigenmann & Eigenmann, 1890
Habitat
Marine
Climate
Deep-water
Body Shape
Fusiform / normal
IUCN Status
LC
Max Length
11.4 cm
Depth Range
10–3400 m
Latitude
20°S – 66°N
Trophic Level
3.2
Resilience
High
Vulnerability
25.00/100
Salinity
30–40 ppt

🔬 Taxonomy

🐟 Physical Description

Dorsal spines (total): 0; Dorsal soft rays (total): 12 - 14; Anal spines: 0; Anal soft rays: 12 - 14; Vertebrae: 34 - 36. Adipose small, narrow based, slender . Brown to black on dorsal surface, lighter ventrally; fins pale . Branchiostegal rays: 9 .: fusiform / normal.

🌀 Behaviour

Behavioural data for California headlightfish is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

🐣 Oviparous

Oviparous .

🌍 Habitat & Distribution

Marine; bathypelagic; depth range 10 - 3400 m , usually 10 - 400 m . Deep-water; 66°N - 20°S Northwest Pacific: throughout subarctic-transitional waters to northern Japan (Ref.

🌿 Ecology

Zone Preferences
🌊 Marine 🌑 Deep Water
Trophic Level
3.2±0.1

📐 Morphometrics

Length–Weight Relationship: W = 0.01023 × L3.04 (TL)
Max TL
11.4cm
Dorsal Rays
13
Anal Rays
13
Vertebrae
35

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2018

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
25.00/100
Low vulnerability
Trophic Level
3.2
Predator
Body Shape
Fusiform / normal
Climate Zone
Deep-water
Latitude Range
66°N – 20°S
Described By
Eigenmann & Eigenmann, 1890

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 15 records indexed .

Occurrence density from GBIF View GBIF records ↗

👥 Community & Contribute

Aquareap Community Observations
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View all observations for California headlightfish ↗
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