Bluefin Leatherjacket
Thamnaconus degeni
Bluefin Leatherjacket is a small to medium filefish known from scattered global occurrence records, but detailed life-history information is limited. It is likely a reef-associated species with a compressed body, suited to sheltering among structure and picking at benthic prey.

Identification points
- Laterally compressed, deep-bodied filefish shape with a small mouth and elongated snout
- Blue to blue-gray sheen across the body, often with darker markings on the head and upper body
- Small first dorsal spine typical of leatherjackets, plus a tapered rear body and rough skin texture
Habitat
Likely associated with warm coastal reefs, rocky structure, and other hard-bottom habitats where it can shelter among cover and feed near the substrate; published ecological detail is sparse for this species.
Bait notes
Little species-specific angling information is published. Small natural baits presented near reef edges or structure, along with tiny soft plastics or jigged lures, are the most plausible approach; it is more likely to be an incidental catch than a targeted game fish.
Behavior
Presumed to feed on small benthic invertebrates and algae picked from hard surfaces, using the filefish-style snout to nip at prey. Like other leatherjackets, it is probably cautious, structure-oriented, and not a fast open-water chaser.
Caution
Species-specific consumption or toxicity warnings are not well documented; check local regulations because occurrence and status information are limited. As with related leatherjackets, handle carefully around the sharp dorsal spine and rough, abrasive skin.
Fishing notes
Fish slowly around reefs, wrecks, and rough bottom with light tackle and small hooks or lures. Present bait close to cover and keep retrieves deliberate; if encountered, handle carefully because leatherjackets often have rough skin and a strong first dash into structure.