Hypseleotris moncktoni, (REGAN, 1908)

HYPSELEOTRIS MONCKTONI ( REGAN, 1908)

( FIGS 1–4, 9; TABLES 4, 5)

Material examined: Holotype (unique): BMNH 1905.8 .15.1, female (59 mm SL); Agajambo, Papua New Guinea, Monckton coll.

Description: Based on the holotype only. The ray and scale counts are given in Table 4 and selected morphometrics in Table 5.

The body is compressed laterally. The body depth at anus is 26% SL, at first dorsal fin 27% SL, and the caudal peduncle depth is 15% SL. Pre-dorsal length 41% SL and preanal length 61% SL. Size: up to 5.9 cm SL.

The head is 26% SL, rounded dorsally with a broad interorbital, the snout is pointed. The mouth (terminal) and jaw length 8% SL are small; jaws oblique with several rows of conical teeth. Posterior end of maxillary ending below or just before posterior nostril before eye. Anterior nostril at the end of a short tube above upper lip; posterior nostril a simple pore in front of eye. Eye diameter 6% SL and interorbital length 8% SL.

Dorsal fins VI–I,8, with no filamentous rays. The first dorsal fin is with second, third, fourth and fifth rays longer. Anal fin I,10 directly opposite to the second dorsal fin. The caudal fin is with 11 branched rays and its posterior margin is straight or slightly rounded. Pelvic fins separate, I,5. Pectoral fins 13. Lateral scales 29, with ctenoid scales on flanks and caudal peduncle. Pre-dorsal scales ctenoid, becoming cycloid anteriorly reaching to snout adjacent to anterior nostril. Ctenoid scales on operculum, on base of pectoral fins and on belly extending to anus. Cheek with cycloid and ctenoid scales. Scales in transverse back series 8, in transverse forward 11, in pre-dorsal 19 and in zigzag usually 6, interorbital scales 4. Gill opening extending to below posterior preopercular margin.

Female has a rectangular or chalice-shaped bulbous urogenital papilla with crenulated outer edges around distal opening.

Cephalic sensory pore system as described by Akihito et al. (1988) with oculoscapular canal nasal to post-temporal with the pores C’, D, E’, K’, L’; preopercular canal long with the pores M’, N, O, P’.

Colour in preservation: Background of body beige to brown on the back and flanks. A thin dark blotch on dorsal half of pectoral fin base. Snout dark. Large lateral black band that extends from the operculum on the caudal peduncle slightly visible or absent. Belly yellowish ( Fig. 9). In his description Regan (1908) wrote ‘each scale of the body yellowish with a broad dark brown margin… vertical fins blackish, the caudal with some light spots’.