Liopropoma lunulatum (Guichenot 1863)

Koeda, Keita, Senou, Hiroshi, Chang, Chih-Wei & Ho, Hsuan-Ching, 2019, Redescription of Liopropoma aragai (Teleostei: Serranidae), with two new confirmed records of species of Liopropoma from Taiwan, Zootaxa 4702 (1), pp. 60-72 : 60-72

Liopropoma lunulatum (Guichenot 1863)

Figure 5 ; Tables 2 , 3

Grystes lunulatum Guichenot 1863 :C-24 (type locality, Réunion).

Liopropoma lunulatum Guichenot 1863 : Randall & Taylor 1988:22, pl. 4E (Ryukyu Archipelago, Guam, Rarotonga Island, Tahiti, Kerala and Réunion); Shen & Wu 2011:385, unnumbered figure (drawing only, no voucher specimen indicated). Nair et al. 2013:1, fig. 2 (Kerala).

Material examined. NMMB-P 9718, 114.9 mm SL, southern Taiwan (purchased at Houbihu fishing port), 6 Sept. 2008, coll. C.-W. Chang.

Description. Counts and measurements of the specimen are given in Tables 2 , 3.

Body moderately elongate, compressed; caudal peduncle depth slightly less than half of body depth. Head pointed, dorsal profile nearly straight; snout length 3.7 in HL; orbit diameter 4.4 in HL; interorbital slightly convex, least bony width 6.4 in HL. Posterior margin of preopercle with slight irregular curve, not obviously serrate. Anterior nostril a thin membranous tube set directly in front of eye on edge of groove separating front of snout from upper lip; posterior nostril with a low fleshy rim, above center of eye. Mouth large, slightly oblique; lower jaw projecting; posterior margin of maxilla not reaching vertical drawn through posterior margin of orbit; upper jaw length 2.3 in HL. Villiform teeth bands on both jaws (up to 15 irregular rows anteriorly on upper jaw), vomer (ca. 6 rows in a broad V-shaped patch) and palatines (long narrow band, 4 or 5 rows wide at broadest point). Tongue slender, end broadly rounded; lips smooth.

Lateral line highly arched over pectoral fin from middle to tip; highest point below base of fifth dorsal-fin spine. Head fully scaled, except around nostrils and large pores on snout; small scales on basal one-third of second dorsal, anal and caudal fins.

Origin of dorsal fin above seventh pored lateral-line scale; first dorsal-fin spine slender, its base close to base of second spine; third spine of dorsal fin longest, its length 3.0 in HL; seventh spine clearly visible above middle of distinct scaly ridge between first and second dorsal fins; fifth soft ray of dorsal fin longest, its length 2.0 in HL. Origin of anal fin below base of third soft ray of dorsal fin; first spine of anal fin shorter than second and third spines, its length 3.7 in HL; second soft ray of anal fin longest, its length 2.0 in HL. Pectoral fins pointed, length 1.4 in HL; fifth ray longest, reaching vertical through base of first soft ray in dorsal fin. Origin of pelvic fin slightly anterior to upper base of pectoral fin; pelvic fin length 2.0 in HL. Caudal fin emarginate, lobes pointed.

Color when fresh. Dorsal one-third of body orange, ventral two-thirds yellow without lateral stripes. A yellow stripe from front of upper lip through eye to upper part of operculum. Posterodorsal edge of maxilla yellow; a patchy yellow stripe running from cheek to anterior of pectoral-fin base. Approximately 20 dark brown spots scattered on dorsal half of body. Dorsal fin red, a broad yellow band basally on spinous portion and anteriorly on soft-ray portion. Anal fin pink, a broad submarginal yellow band anteriorly. Caudal fin light red becoming pink distally on central portion; upper and lower lobes broadly yellow (yellow of lower lobe continuous with yellow stripe on lower part of caudal peduncle); pectoral fins light red; pelvic fins pink. Iris purple with yellow band laterally thorough pupil.

Color when preserved. Body and fins pale without dark stripes; dorsal half of body with ca. 20 dark spots, background a little darker due to slight dusky edges on scales.

Distribution. Liopropoma lunulatum has been recorded from Okinawa Island (Ryukyu Archipelago, Japan), Guam, Rarotonga Island ( Cook Islands), Tahiti, Kerala ( India), Réunion ( Randall & Taylor 1988; Senou 2013; Nair et al. 2013). The present specimen is the first record from southern Taiwan and the South China Sea.

Remarks. Most morphological characters of NMMB-P9718 agree well with the diagnosis of L. lunulatum given by Randall & Taylor (1988): dorsal fin continuous, all spines and rays connected above their bases by membranes; dorsal-fin soft rays 12; eighth dorsal-fin spine longer than sixth and seventh; anal-fin soft rays 8; pectoral-fin rays 15; lateral-line scales 46; gill rakers 6 (upper) + 13 (lower); caudal fin deeply emarginate; head fully scaled; scattered small dark spots on body, especially posteriorly.

Liopropoma lunulatum closely resembles L. aragai and L. lemniscatum , sharing many morphometric characters. However, L. lunulatum is easily distinguished by the small dark spots scattered laterally on the body (absent in the other two species). Although L. randalli Akhilesh, Bineesh & White 2012 has similar laterally-scattered spots, it also has a broad black stripe from behind the eye to the caudal peduncle (versus absent in L. lunulatum ) ( Akhilesh et al. 2012). Although the coloration of L. lunulatum is similar to that of L. aurora , endemic to the Hawaiian Islands, the latter has 13 dorsal-fin rays and 8 anal-fins rays.

Liopropoma lunulatum (as Chorististium lunulatum ) was first reported from Taiwan by Shen (1984), but the provided photograph was actually of Chelidoperca hirundinacea (Valenciennes 1831) . This seems to have been fol- lowed by Shen & Wu (2011), who included a drawing but no voucher specimen. Accordingly, the present specimen from southern Taiwan represents the first confirmed record of L. lunulatum in that region.

Figures

FIGURE 5. Specimen of Liopropoma lunulatum (NMMBA-P9718, 114.9 mm SL) from Taiwan. A: fresh specimen; B: preserved specimen.