Western blue skate

📖 Overview

Western blue skate (Notoraja hesperindica), first described by Weigmann, Séret & Stehmann, 2021 is a large fish in the family Arhynchobatidae (order Rajiformes). Adults typically reach 53.30 cm in maximum length. It inhabits marine coastal and open-ocean environments. Recorded depth range: 1230 to 1600 metres. It occurs in Deep-water 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 Least Concern.

🔬 Taxonomy

🐟 Physical Description

This species is distinguished from most of its congeners by the intense dark blue-grayish coloration and large dorsolateral tail thorns. It is further distinct with the following characters: disc evenly inverse heart-shaped, with broadly rounded outer corners; body length to mid-cloaca is shorter than tail length from mid-cloaca; snout very long direct preorbital length 15.1-16.7% TL.; orbits are relatively small, horizontal diameter 0.9-1.2 times interorbital width; dorsal surface nearly completely devoid of denticles except the trunk area close to pectoral axils where bands of few denticles start and continue as more pronounced rows on tail; anterior tail with several short rows of spinules and a rather regular row of small spinules on lateral tail; one small preorbital thorn on each side; a regular or irregular row of about 16-25 small median tail thorns; lateral tail with 2 irregular rows of about 15-25 dorsolateral thorns that are much larger than the median thorns. Colouration when fresh, the dorsal disc plain intense dark blue, somewhat mottled blackish-brown in the orbital and snout regions, pelvic fins and claspers medium brownish blue, tail dark blackish blue; the ventral surface dark .Cross section: flattened.

🌀 Behaviour

Behavioural data for Western blue skate is currently being reviewed.

🦐 Diet

🥚 Reproduction

🌍 Habitat & Distribution

Marine; bathydemersal; depth range 1230 - 1600 m . Deep-water Indian Ocean: off southern Mozambique and off northwestern Madagascar.

🌿 Ecology

📐 Morphometrics

🌡️ Water Parameters & Tolerance

🛡️ Conservation Assessment

📊 Population Risk & Fisheries

🐠 Related Species

🔍 Similar Species

👥 Community & Contribute