Roughspine Seabass

materials_examined

Material: 2 specimens in total. Anda 3 (1) RGM 962252; AndaCliff 3 (1) RGM 962253. One adult specimen (OL = 3.73, OH = 2.45 mm) is available that resembles recent otoliths of Parascombrops serratospinsus, which is encountered in the West Pacific seas (Schwarzhans & Prokofiev, 2017). However, the shape of our specimen is less compressed. A similar variation in compactness is also observed in Parascombrops aff. mutinensis (Bassoli, 1906) otoliths known in large numbers from the Mediterranean Pliocene, but on average these latter otoliths are also more compressed and have a more rounded dorsal rim. More specimens are needed for a definitive species identification.

Fish Otoliths from the Cabarruyan Piacenzian-Gelasian fauna found in the Philippines

description

Description. Counts and measurements are summarized in Tables 2 – 7. Snout bluntly rounded; interorbital space convex. Posterior edge of maxillary weakly concave with postero-dorsal and postero-ventral angles slightly sharp and postero-ventral angle extended downward and slightly backward resulting in slightly oblique posterior margin of maxillary. Preopercular lobe without longitudinal ridges; hind margin of interopercle and lower part of subopercle strongly serrated; inner edge of preopercle with 4 – 8 small denticles not extending along ventral branch. Two anal-fin spines, the second serrated. Second spine of first dorsal fin and spine of second dorsal fin serrated. Pelvic fin spine serrated along its outer edge. First anal-fin pterygiophore broad, straight, with broad hollow tip, reaching last pair of pleural ribs. First haemal spine with a narrow posterior expansion. Dentition. Premaxilla with a pair of strong canines near symphysis, followed posteriorly by a wide band of minute conical teeth. Dentary with a pair of strong canines and a band of small conical teeth near symphysis, followed by a row of small conical teeth and 2 – 4 enlarged canines. Vomer triangular with small p

Reappraisal of Synagrops Günther, 1887 with rehabilitation and revision of Parascombrops Alcock, 1889 including description of seven new species and two new genera (Perciformes: Acropomatidae)

diagnosis

Diagnosis. Small deep-bodied species with convex dorsal head profile. Second spine of first dorsal fin, spine of second dorsal fin and second spine of anal fin serrated in addition to spine of pelvic fin. Anal fin II + 7. Pectoral fin with 14 – 16 rays, pectoral length 20.3 – 26.5 % SL. Gill rakers 13 – 16. Pseudobranchial filaments (13) 16 – 21. First anal-fin pterygiophore long, straight, with broad tip and hollow. Palatines and ectopterygoids moderately wide, with 1 – 2 rows of denticles. Orbital diameter 11.7 – 13.6 % SL. Posterior edge of maxillary plate slightly concave. No longitudinal ridges on preopercular lobe. Otolith very compressed (OL: OH = 1.35 – 1.4).

Reappraisal of Synagrops Günther, 1887 with rehabilitation and revision of Parascombrops Alcock, 1889 including description of seven new species and two new genera (Perciformes: Acropomatidae)

discussion

Discussion. Parascombrops serratospinosus is a small, robust species and is readily recognized by the presence of serration on the pelvic spine, and the second spine of the first dorsal, the spine of the second dorsal, and the second spine of the anal fin. It is further characterized by the most compressed otoliths found in the genus. The only other species with an additional serrated spine is P. spinosus from the western tropical Atlantic, which lacks a serrated spine on the second dorsal fin, has longitudinal ridges on the preopercular lobe, has the first anal-fin pterygiophore sharply pointed, not hollow, and has much more elongate otoliths (OL: OH = 1.75 – 1.8 vs 1.35 – 1.4). Geographic and bathymetric distribution. Parascombrops serratospinosus is a common species throughout the Western Pacific, from Taiwan and the Philippines to northwestern Australia and Vanuatu. It is rare off Japan. Its distribution appears to be somewhat patchy: is common to abundant when caught, but absent from many intermediate locations for no obvious reason. Parascombrops serratospinosus has been generally caught at greater depths (predominantly 300 – 600 m) than, for instance P. philippinensis (predo

Reappraisal of Synagrops Günther, 1887 with rehabilitation and revision of Parascombrops Alcock, 1889 including description of seven new species and two new genera (Perciformes: Acropomatidae)