Schismatogobius tuimanua, Keith & Lord & Larson, 2017

Keith, Philippe, Lord, Clara & Larson, Helen K., 2017, Review of Schismatogobius (Gobiidae) from Papua New Guinea to Samoa, with description of seven new species, Cybium 41 (1), pp. 45-66 : 49-50

Schismatogobius tuimanua , new species

( Figs 1 , 2A , 3 , 4 ; Tabs I-III)

snout rather pointed. Mouth oblique. Lower jaw tip anteriormost, reaching a vertical at the middle of the eye; jaw length 32-33% of HL. Eyes high on head, close together with interorbital width about third to half of eye diameter. Anterior nostril short and tube-like.

Dorsal fins VI-I,9, membrane in first dorsal fin posterior to spine 6 not connected at base of spine in second dorsal fin. D1 with all spines about equal in length. Anal fin I,9, origin slightly behind or approximately below second dorsal fin origin. Caudal fin with 11-12 branched rays, posterior margin rounded. Pectoral fins oblong with posterior margin pointed and 13(1)-14(2) rays ( Tab. I), only ventralmost ray unbranched. Pelvic fins always I,5 with both fins joined together for their entire length between rays 5 to form a strong cup-like disc; between spines a well developed frenum, slightly lobed; fins not extending beyond anus. Morphomeristic data are given in table III.

Tongue (anterior tip) bilobed. Teeth in upper jaw (12-15) in two or three rows, teeth conical on sides and only slightly recurved across front. Teeth in lower jaw (10-14) usually in two rows of teeth anteriorly and single row laterally, all teeth very small, conical, with outer row teeth only slightly enlarged and somewhat recurved.

Cephalic sensory pore system always with pores B, D, F, K, L, N and O, pore D singular with all other pores paired; oculoscapular canal absent between pores F and K. Anterior rior oculoscapular canal terminating laterally on each side of head at pore F, just behind posterior edge of eye. Posterior oculoscapular canal with 2

terminal pores, K and L; preopercular canal with

2 pores, N and O. Cutaneous sensory papillae not well developed and inconspicuous due to preservation.

Sexual dimorphism unknown. Urogenital papilla of female broadly oval in ventral view.

Colour in preservation ( Fig. 3B )

Female: usually with three vertical black bands in dorsal view; first band below the first dorsal fin, second band below middle to posterior part of second dorsal fin and third band, the small-

er one, at base of caudal fin. Ventral part of body mostly cream coloured, tan to grey and brownish dorsally; belly whitish; lateral body colour markings mottled. Head dusky; ventral surface of head and isthmus dusky ( Fig. 2A ). First dorsal fin with three longitudinal black bands or rows of black spots; basal band wider. Second dorsal fin mostly cream to tan with black spots in rows on membrane and rays. Caudal fin cream to tan with large black blotch on basal part of fin, blotch extending back toward two oval white patches on upper and lower mid-part of fin; blackish spots and mottling above and below black blotch; patterns on proxi-

mal half of fin usually with bolder markings than those on distal half. Anal fin mostly cream with dusky pigmentation at base. Pelvic disc banded with two to three rows of black spots, membrane between fifth rays clear, frenum mostly without markings, sometimes with a middle black blotch,

distal margin of disc mostly clear. Pectoral fins tan, striped anteriorly with about 4-5 irregular blackish bars; dark spot visible on posterior upper part. The general aspect of the female in preservation is mottled (grey, white and cream), with a cream belly; rows of black spots clearly visible on pectoral fins and clear pattern of the caudal fin.

Colour in life ( Fig. 3A )

Three vertical black bands in dorsal and lateral view. First black band under first dorsal fin,

second black band under second half, and extending posteriorly, of second dorsal, third black band at base of caudal fin. Lateral and dorsal parts of body between the three vertical black bands on the body reddish: interspaces between black bands whitish to cream coloured, finely mottled with orange reticulation and spotting, becoming more dense and less reticulate on head and nape. Belly Figure 2. – B, C : 14-15 pectoral rays.

Figures

Figure 1. – Bayesian phylogenetic reconstruction, based on the partial COI barcode region (636 bp). The posterior probability values are given at each node. Following each species name is the country the specimen comes from; the numbers following the species are the numbers given on the field.

Figure 2. – A-F: Schematic drawings of the ventral surface of head of Schis- matogobius species from Papua New Guinea to Samoa. A: 13-14 pectoral rays.

Figure 3. – A: Schismatogobius tuimanua n. sp., female, 18.9 mm SL (Photo P. Gerbeaux). B: Schismatogobius tuimanua, holotype, MNHN 2016-0263, female, 20.8 mm SL (Photo P. Keith).

Figure 4. – Distribution area of Schismatogobius species from Papua New Guinea to Samoa.