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🌊 Marine Data Deficient 🌡️ Tropical

Day's thryssa

Thryssa dayi Wongratana, 1983
Max Length
21.5 cm
Max Weight
-
Lifespan
-
Trophic Level
3.4
Depth
0–50 m
Climate
Tropical
Resilience
High
Vulnerability
27.00/100
Typical Length
-
Depth Zone
pelagic

📖 Overview

Day's thryssa (Thryssa dayi) is a ray-finned fish of the family Engraulidae. It inhabits marine (saltwater) waters in pelagic environments. This species can reach a maximum total length of 21.5 cm. It occurs at depths between 0 and 50 metres. With a trophic level of 3.4, it is a low-level carnivore, feeding on invertebrates and small organisms. It is assessed as Data Deficient on the IUCN Red List.

Scientific Name
Thryssa dayi
Authority
Wongratana, 1983
Habitat
Marine
Climate
Tropical
Body Shape
Elongated
IUCN Status
DD
Max Length
21.5 cm
Depth Range
0–50 m
Trophic Level
3.4
Resilience
High
Vulnerability
27.00/100
Salinity
30–40 ppt

🐟 Physical Description

Dorsal spines (total): 0; Anal spines: 0; Anal soft rays: 41 - 46. Belly with 25 to 27 keeled scutes from isthmus to anus. Tip of snout a little above level of eye center. Maxilla long, reaching to pectoral fin base; first supra-maxilla minute, oval; teeth in jaws enlarged. Tip of first pectoral fin ray elongated into a short filament. Gill arches pinky orange, basibranchials black, inside of gill cover pale yellow or golden.: elongated; Cross section: compressed.

🌀 Behaviour

Behavioural data for Day's thryssa 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; pelagic-neritic; depth range 0 - 50 m . Tropical; 27°N - 6°N, 64°E - 78°W north to Pakistan, possibly to Gulf of Oman.

🌿 Ecology

Zone Preferences
🌊 Marine 🐟 Pelagic
Trophic Level
3.4±0.5
🐠 Schooling

📐 Morphometrics

Length–Weight Relationship: W = 0.00407 × L3.14 (TL)
Max TL
21.5cm
Anal Rays
44

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Data Deficient
Assessment Date
2018

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
27.00/100
Low vulnerability
Trophic Level
3.4
Predator
Body Shape
Elongated
Climate Zone
Tropical
Described By
Wongratana, 1983

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