Taxonomy of Finfish (1+2)

3.3.11.3 Monocanthidae (Filefishes/Leatherjackets)

• Smooth to rough shagreen - like skin, minute scales with fine spicules.
• Two dorsal fin spines; the first being large and armed with downward - curving barbs; the second spine very small and capable of locking the first in an upright position.
• Rudimentary pelvic fins, a series of 3 or fewer pairs of enlarged scales encasing the posterior end of the pelvis, projects through the skin, or a single scale seen anterior to the posterior end of the pelvic, disappears with age or entirely absent.

Eg. Alutera monoceros

Similar Families

Triacanthidae - Dorsal fin spines 2 to 6; a strong pair of pelvic fin spines.

Balistidae - 3 dorsal fin spines; pelvic fin with rudimentary spines or absent; scales longer; skin not shagreen like.

Ostracidae - Dorsal fin without spines; pelvic fin absent; thick enlarged scales as hexagonal plates sutured to form a box-like encasement of the body.

Tetraodontidae/ Diodotidae/ Triodontidae/Molidae - No obvious spiny dorsal fin/pelvic fin absent, skin either rough with scales or scales absent with smooth skin.