Trimma taipinensis, Chang & Shen & Chen, 2025

Trimma taipinensis new species

( 太ẓšâḛḭ)

( Figs. 1–2 View FIGURE 1 View FIGURE 2 )

Material examined

Holotype

NTOUP-TPI-20230624-2, 12.4 mm SL, Taiping Island , South China Sea, June 24, 2023 coll. Harefa et al.

Diagnosis

The new species of Trimma taipinensis can be well distinguished from other congeners by following unique combination of features: (1) fin ray counts D2 I/7, A I/7, P 17, V with complete sucking disc; (2) squamation including LR 29–30, TR 9, SDP 9, PreD 7, opercle with large scales; (3) no any canal pores; and (4) distinctive colouration: body pale white background with lower half entirely orange yellow. Three cross bands in front of first dorsal fin origin; seven major vertical crossing bands after origin of first dorsal fin. Head with one red bar crossing snout to both jaws, another one vertical red stripe below eye, a vertical red band crossing the edge of preopercle. Nape with two orange red bands. Pectoral fin pinkish to orange, its basal region with two rounded snow white marks. Caudal fin entirely pinkish orange. No any black blotch on caudal fin base.

Description

Body proportion in Table 1 View TABLE 1 . Body moderately elongated, slightly compressed posteriorly.Head slightly depressed anteriorly. Mouth oblique, maxilla extending posteriorly to midline vertical of orbit. Lower jaw protruding slightly beyond tip upper jaw. Anterior nasal with a short tapering tube reaching anteriorly to above anterior margin of upper lip, posterior one as opening pore. Eyes large, dorsolateral. Interorbital rather narrow, with shallow trench and postorbital trench with slightly groove. Cheek slightly fleshy. Gill-opening on each side large, extending anteroventrally to vertical drawn through posterior edge of mid-pupil. VC =26.

Fins.—D1 VI, D2 I/7, A I/7, V I/5, P 17. First dorsal fin with no filamentous rays, all spinous rays about equal except sixth spinous ray shorter and rather distance from others, its rear tip extending to origin of second dorsal fin when depressed. 1 st segmented ray of second dorsal-fin usually unbranched, remaining rays branched, most posterior element with two rays. 1 st segmented ray of anal-fin usually unbranched, 2 nd segmented ray branched except in two specimens, remaining rays all branched, most posterior element with two rays. Rear margins of second dorsal fin and anal fin not reaching the procurrent rays of caudal fin when depressed. Pectoral fin rays not branched. Pelvic fin united with frenum and basal membrane, forming an oblong sucking disc. Caudal fin distal margin truncate.

Scales.—LR 29–30, TR 9, SDP 9, PreD 7. No scales on cheek but covered scales on operculum. Predorsal scale extension to full covered on nape, then terminating just behind eye.

Head lateral-line system.— ( Figure 2 View FIGURE 2 )

Canals: No canal pore on head.

Sensory papillae: Sensory papillae or free neuromast distributed as follows,: row a long, extending to beyond midline of orbit; rows b and d short;; row c present longitudinally; single cp papilla; rows ot and o i well separated.