Peristedion longicornutum, a new species of armored gurnard from the western Pacific Ocean (Teleostei: Peristediidae).

The Longhorn Armored Gurnard Peristedion longicornutum n. sp. is described from Papua New Guinea, Solomon Islands, and Vanuatu, based on 28 specimens collected with a beam trawl at depths of 340–506 meters. The new species is characterized among the Indo-Pacific species of the genus by 21–23 dorsal-fin soft rays; 20–22 anal-fin soft rays; 29–33 bony plates in the dorsal row; 35–38 in the upper lateral row; 26–29 in the lower lateral row; 23–26 in the ventral row; 3 lip and 6–7 chin groups of barbels; 14–26 branches on the filamentous barbel; 15–24 total chin barbels; the anterior edge of the 4th sensory pore of the rostral projection half a pupil diameter anterior to the anterior edge of the premaxilla; a very long and needle-like rostral projections, length 14.2–22.3% SL; a wide interspace between rostral projections, 0.20–0.30 in rostral-projection width, and a rounded margin on the medial side at the base; a smooth and straight perifacial rim; the upper detached pectoral-fin ray longer than the joined pectoral fin; and the peritoneum pale. A key to the Indo-West Pacific species of the genus Peristedion Lacepède, 1801 is presented.