Tuesday, August 15, 2017

[Ichthyology • 2017] Parapercis binotata • A New Species of Parapercis (Teleostei: Pinguipedidae) from the Solomon Islands


Parapercis binotata Allen & Erdmann, 2017

Abstract

A new species of pinguipedid fish, Parapercis binotata, is described from the Solomon Islands on the basis of six adult specimens, 46.5–56.5.5 mm SL. The new taxon belongs to the Parapercis cylindrica complex, which contains five other western Pacific Ocean species: P. australis, P. cylindrica, P. haackei, P. lineopunctata, and P. snyderi. It is most similar to P. lineopunctata from the East Indian Archipelago, but adult males are clearly distinguished by the presence of two short black bands, one on the cheek and another on the lower pectoral fin. Although lacking these markings, females differ from those of P. lineopunctata by the presence of a curved black band below the eye. The only known habitat of the new species consists of a nearly enclosed lagoon in 4-8 m depth. Analyses of the mtDNA “barcode” marker COI sequences for the P. cylindrica species complex show exceptionally deep divergences between most species, about 15–20% divergence between all but one pair of species, with P. binotata 14.52% different from its nearest relative, P. lineopunctata.
  
Key words: taxonomy, systematics, ichthyology, coral-reef fishes, Indo-Pacific Ocean, sandperch, DNA barcoding. 

Figure 2. Parapercis binotata, underwater photographs at Mbanika Island, Russell Group, Solomon Islands.
A & B: adult males, approximately 50–55 mm SL; C & D: females, approximately 35–40 mm SL (G.R. Allen).

Parapercis binotata, n. sp. 
Solomons Sandperch

Diagnosis. Dorsal-fin rays V,21; anal-fin rays I,16–17; pectoral-fin rays 14–16; lateral-line scales 46–48; four, progressively larger, recurved canine teeth on each side at front of lower jaw; scales on body ctenoid except cycloid on prepelvic area; opercle and cheek covered with ctenoid scales; body depth 4.7–5.5 in SL; caudal fin truncate to slightly rounded; pelvic fins reaching beyond anal-fin origin; color of head and body generally white, 7–8 short brown bars on back, above lateral line and lower side with corresponding narrow yellow-orange to brown bars; adult with conspicuous black band on rear edge of cheek and short black band on lower pectoral-fin rays; females with curved black band under eye along lower edge of suborbital; found on sand substrates in depths of less than 10 m.

Etymology. The species is named binotata (Latin: two markings), with reference to the diagnostic dark bands on the cheek and pectoral fins of males. It is treated as a feminine singular compound adjective.

Distribution and habitat. The new species is known only from the Solomon Islands type locality. The relatively unusual habitat consisted of a nearly enclosed, narrow, dead-end lagoon (Fig. 3) with a gradually sloping, white sand bottom with scattered, mainly low-profile, coral formations. The fish was common at depths between about 4–8 m, generally occurring as solitary individuals

   
Gerald R. Allen and Mark V. Erdmann. 2017. A New Species of Parapercis (Teleostei: Pinguipedidae) from the Solomon Islands.  Journal of the Ocean Science Foundation. 27, 8–19. http://www.oceansciencefoundation.org/josf27b.html