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🌊 Marine Data Deficient 🌡️ Temperate

Grammonus Yunokawai

Grammonus yunokawai Nielsen, 2007
Max Length
9.8 cm
Max Weight
-
Lifespan
-
Trophic Level
3.4
Depth
-
Climate
Temperate
Resilience
High
Vulnerability
19.00/100
Typical Length
-
Depth Zone
demersal

📖 Overview

Known only from one female specimen with ovaries containing eggs up to about 0.5 mm in diameter and apparently with no embryos. It was caught by hand in the back of the cave in absolute darkness. The head and lateral line pore systems are well developed, also the sensory papillae on the head and body, indicating adaptation to the lightless environment Also observed and caught were a shrimp Parhippolyte misticia and the fishes Pseudamia hayashiiand Apogon evermanni .

Scientific Name
Grammonus yunokawai
Authority
Nielsen, 2007
Habitat
Marine
Climate
Temperate
IUCN Status
DD
Max Length
9.8 cm
Trophic Level
3.4
Resilience
High
Vulnerability
19.00/100
Salinity
30–40 ppt

🐟 Physical Description

Dorsal soft rays (total): 83; Anal soft rays: 64; Vertebrae: 41. This species has the following characters: Dorsal-fin rays 83; anal-fin rays 64; caudal fin rays 9; pectoral 23-24; vertebrae 12 + 29; anterior anal fin ray is placed below 23rd dorsal fin ray; maximum depth of head is 32.0% SL; predorsal length 41.5% SL; interorbital width 10.5% SL; height of posterior margin of maxilla 8.4% SL .

🌀 Behaviour

Behavioural data for Grammonus Yunokawai 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; depth range ? - 20 m . Temperate Northwest Pacific: Japan.

🌿 Ecology

Zone Preferences
🌊 Marine ⬇️ Benthic
Trophic Level
3.4±0.5

📐 Morphometrics

Length–Weight Relationship: W = 0.00468 × L3.03 (TL)
Max TL
9.8cm
Dorsal Rays
83
Anal Rays
64
Vertebrae
41

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Data Deficient
Assessment Date
2019

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
19.00/100
Low vulnerability
Trophic Level
3.4
Predator
Climate Zone
Temperate
Described By
Nielsen, 2007

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