Cymatognathus aureolateralis Kimura & Johnson & Peristiwady & Matsuura 2017, sp. nov.

Cymatognathus aureolateralis sp. nov.

New English name: Wavy Jaw Slopefish (Figure 1A; Table 1)

Holotype: MZB 19251 (formerly LBRC-F 2837), male, 181 mm SL, fish market at Tanjung Kodok, Bitung, North Sulawesi, Indonesia, hook and line, no depth data, 2 May 2012, collected by T. Peristiwady.

Figures in parentheses indicate counts on right side.

Paratypes: FRLM 54552 (formerly LBRC-F 2918), male, 178 mm SL, Girian Fish Market, Bitung, North Sulawesi, Indonesia, hook and line, no depth data, 13 July 2012; collected by T. Peristiwady (partly dissected to observe the cranium and suspensorium); LBRC-F 3374, male, 184 mm SL, Girian fish market, Bitung, North Sulawesi, Indonesia, hook and line, no depth data, 17 June 2013, collected by T. Peristiwady.

Diagnosis. See generic diagnosis.

Description. Characters given in the familial and generic diagnoses and generic description are not repeated except for counts. Counts and measurements are shown in Table 1. Body deepest at base of fifth dorsal-fin spine; body width slightly less than half of body depth; mouth oblique, forming an angle of about 50° to horizontal axis of body; palato-premaxillary ligament between anteriormost part and head of premaxilla thick and short, passes over head of maxilla (Figure 4 A); snout rounded and bulging at tip but concave dorsally just behind tip of snout; interorbital area broad, convex; scaly area on head anteriorly extending beyond level of anterior nostrils, reaching just behind tip of snout dorsally; narrow naked area on snout just below nostrils; tip of snout and throat with villiform papillae; second and third infraorbitals each with small, blunt retrorse spine posteroventrally; gill rakers long, longest ca. 1.2 times length of longest gill filament; cephalic sensory system developed: two pores on snout, four on infraorbitals, 19 in temporal region and five on lower jaw; dorsal-fin origin located just above tip of upper opercular spine; membranes between dorsal- and anal-fin spines deeply incised; first dorsal-fin spine short, the second more than half of the third, the fourth longest, the fourth to ninth (last) spines progressively shorter; length of last spine almost twice that of the first (including holotype) or more, about equal to that of the first soft ray; eighth dorsal-fin soft ray longest, first to eighth soft rays gradually increasing posteriorly in length; all dorsal-fin soft rays branched; length of first anal-fin spine about half or two-thirds (including holotype) that of the second, third spine longest, slightly longer than the second; all anal-fin soft rays branched; second (holotype), third or fourth soft ray longest; pectoral fin long, about equal to length of head but shorter than body depth, reaching to a vertical through base of first (including holotype) or second anal-fin soft ray, tip pointed, all but uppermost and lowermost rays branched, fourth ray longest, fifth to lowermost rays progressively shorter; all pelvic-fin soft rays branched, length of spine shorter than first soft ray; first soft ray longest, tip forming a filament, first to fifth soft rays progressively shorter; dorsal- and anal-fin bases covered by small scales forming scaly sheath; small scales on caudal fin extending almost to its posterior margin; small scales on proximal one-fifth of pectoral fin and one-third of pelvic fin; pelvic-fin axil with two lanceolate scales.

Color when fresh (Figure 1A). Head and body deep pink dorsally grading to paler ventrally; a large bright yellow blotch mid-laterally on body; several yellow blotches on snout, occiput, surroundings of orbit, and cheek; dorsal-fin spines and soft rays mostly pale pink; soft portion of dorsal fin yellowish distally; anal- and pelvic-fin rays pinkish, dorsal-, anal-, and pelvic-fin membranes whitish; pectoral and caudal fins pinkish orange, posterior margin of caudal fin whitish.

Color of preserved specimens. Head, body and fins pale brownish uniformly.

Distribution. Currently known only from Bitung, North Sulawesi, Indonesia. No data on accurate depth is available, but according to a fisherman, the type specimens were collected as bycatch of hand-lining targeting Priacanthus Etelis, and Pristipomoides. These fishes are found at depths between 15 and 400 m (Anderson & Allen, 2001; Starnes, 1999). Recently the third author obtained a video clip that clearly shows C. aureolateralis sp. nov. in situ (a still image acquired from the video is shown in Figure 9). The video was taken off Lembeh Island, near Bitung, North Sulawesi, Indonesia, at a depth of 199 m on 12 November 2015, by an ROV as part of an ongoing survey of the Indonesian coelacanth.

Etymology. The specific name “ aureolateralis ” is derived from Latin aurum (gold) and lateralis (side) in reference to the bright yellow marking laterally on body.

Remarks. Although C. aureolateralis clearly differs from members of the genus Symphysanodon (except for S. octoactinus) in having a much deeper body than the latter (Anderson 1970, Anderson & Springer 2005; Figure 1), it shares the following characters with the latter, in addition to those indicated in the familial diagnosis: upper and lower corners of upper jaw rounded; upper lip posteriorly covered by maxilla; and caudal fin deeply forked with tips of both lobes filamentous (Figure 1). Hypurals 3 and 4 are fused in both Cymatognathus and all species of Symphysanodon, except S. octoactinus. Hypurals 1 and 2 are autogenous in Cymatognathus and in about half of the species of Symphysanodon. Of the shared characters listed in the familial diagnosis, the following characters are unique among basal percoids (sensu Johnson, 1984) and to both Symphysanodon and Cymatognathus, and are considered as synapomorphies of the family Symphysanodontidae: supraneural and dorsal-fin pterygiophore insertion pattern 0/0/0+2+1/1/ (S. octoactinus exceptional); T-shaped first supraneural; foreshortened base of penultimate ventral procurrent caudal-fin ray; palato-premaxillary ligament passing from anteriormost part of palatine, across head of maxilla, to ascending process of premaxilla; and well-developed outer tooth patches at tips of both jaws, those of the lower jaw received into spaces between those of the upper jaw. Cymatognathus aureolateralis is distinguishable from members of Symphysanodon by important characters described in the generic diagnosis, in particular the wavy contour of the lower jaw created by abrupt depression of posterior tip of the coronoid process of the dentary so that teeth on the anterior portion appear as an almost centrally-located elevated tooth patch, and the horizontally slit-like posterior nostril.

Cymatognathus aureolateralis superficially resembles Giganthias (Giganthiidae), comprising Giganthias immaculatus Katayama, 1954 and G. serratospinosus White & Dharmadi, 2012, in having tooth patches with robust conical teeth on the tip of lower jaw, and a deep compressed body with red and yellow coloration (Figure 10). However, Cymatognathus clearly differs from Giganthias in having an obviously “elevated” tooth patch posteriorly on the lower jaw (vs. no elevated tooth patch on lower jaw in Giganthias; Figure 10 C), smaller teeth on the jaws short and conical (vs. slender and curved inward; Figure 10 B, C), endopterygoids and ectopterygoids with small conical teeth (vs. edentate), upper lip posteriorly covered by maxilla (vs. not covered), lateral line gently curved anteriorly (vs. steeply curved), a single, un-notched dorsal fin with ten soft rays (vs. notched with 13–14 soft rays; Figure 10 A), anal fin with seven soft rays (vs. eight), tips of all dorsal- and pelvic-fin spines smooth (vs. tips of second, third and/or fourth dorsal- and pelvic-fin spines serrated), supraneural bones three, the first Tshaped, the third inserting together with the first two dorsal pterygiophores in the second interneural space (vs. two, the first not T-shaped and only the first dorsal-fin pterygiophore inserting in the second interneural space), hypurals 3 and 4 fused (vs. all hypurals autogenous), and the penultimate ventral procurrent caudal-fin ray with foreshortened base (vs. not foreshortened). Cymatognathus aureolateralis can be also distinguished from the Anthiadinae by the latter two characters and Callanthiidae by the last as well as having 25 vertebrae (vs. 26–28 in the Anthiadinae, and 24 in the Callanthiidae and Serranidae except for Anthiadinae) and opercle with two flat spines (vs. three). Accordingly, we establish Cymatognathus as a new genus in the family Symphysanodontidae.

Johnson (1981) described a posteroventral projection of the metapterygoid overlapping the symplectic in S. berryi Anderson, 1970 as a diagnostic feature of Symphysanodon. Our observations indicate that it is not present in all species of Symphysanodon (e.g., present in S. andersoni, but not in S. katayamai, Figure 8 B, C) and is therefore not diagnostic for the genus. It is also absent in Cymatognathus (Figure 8 A).

The dentition is better developed in males than females of S. berryi and S. disii Anderson, Baranes & Goren, 2011 (Anderson et al., 2011). The outer tooth patches of a male S. andersoni (USNM 435866) are also much larger than those of the female (USNM 440280). However, sexual dimorphism in C. aureolateralis is unknown because no female specimens of the genus have been collected. The teeth in the jaws and on the palatines and pterygoids are more developed in Cymatognathus than even in male Symphysanodon (Figures 2, 3, 7, 8).

Comparative materials. Symphysanodontidae — Symphysanodon andersoni: USNM 435866, male, 200 mm SL, Salalah, Dhofar, Oman; USNM 440280, female, 168 mm SL, Somalia. Symphysanodon berryi: USNM 204086, holotype, 113 mm SL, Great Inagua Island, Bahamas. Symphysanodon katayamai: FRLM 11738 *, male, 155 mm SL, Shima, Mie, Japan; FRLM 25765, 90.4 mm SL, Bitung, North Sulawesi, Indonesia; KAUM-I. 5 6003, male, 159 mm SL, Iloio, Panay, Philippines. Symphysanodon maunaloae Anderson, 1970: USNM 204389, holotype, 67.5 mm SL, Hawaii. Symphysanodon mona Anderson & Springer, 2005: USNM 371386, holotype, 86.6 mm SL, Mona Passage, off western Puerto Rico. Symphysanodon octoactinus: USNM 204084, holotype, 79.7 mm SL, Grand Bahama Island, Bahamas. Symphysanodon parini Anderson & Springer, 2005: USNM 372776, holotype, 114 mm SL, Sala y Gomez Ridge, southeastern Pacific. Symphysanodon typus Bleeker, 1877: FRLM 25766 *, 103 mm SL, Bitung, North Sulawesi, Indonesia; NSMT-P 63382, 63383, 83.1–98.6 mm SL, Bitung, North Sulawesi, Indonesia. Symphysanodon xanthopterygion Anderson & Bineesh, 2011: USNM 400886: holotype, 141 mm SL, Quilon, Kerala, India. Callanthiidae — Callanthias japonicus Franz 1910: FRLM 32588, 44915 *, 153–160 mm SL, Shima, Mie, Japan. Grammatonotus surugaensis Katayama, Yamakawa & Suzuki, 1980: FRLM 45675: 87.0 mm SL, Minamiise, Mie, Japan. Giganthiidae — Giganthias immaculatus: FRLM 3665: 206 mm SL, Shima, Mie, Japan; FRLM 50837: 257 mm SL, Torishima I., Ogasawara Is., Japan; FRLM 52792 *, 52793: 218–245 mm SL, Naha, Okinawa, Japan; LBRC-F 1380, 205 mm SL, Bitung, North Sulawesi, Indonesia; NSMT-P 18654, holotype, 252 mm SL, off Izu- Oshima, Tokyo, Japan; URM-P 0 3764, 39792, 240– 268 mm SL, Naha, Okinawa, Japan. Anthiadinae (Serranidae) — Caprodon schlegelii Günther, 1859: FRLM 33363, 129 mm SL, Shima, Mie, Japan. Odontanthias borbonius (Valenciennes in Cuvier & Valenciennes, 1828): FRLM 25767, 34847, 84.9–91.9 mm SL, Bitung, North Sulawesi, Indonesia. Odontanthias chrysostictus (Günther, 1872): FRLM 34846, 40182, 129– 132 mm SL, Bitung, North Sulawesi, Indonesia. Odontanthias unimaculatus (Tanaka,1917): FRLM 40181, 101 mm SL, Bitung, North Sulawesi, Indonesia; FRLM 45676, 126 mm SL, Minamiise, Mie, Japan. Plectranthias japonicus (Steindachner in Steindachner & Döderlein, 1883): FRLM 47681, 47682, 90.4–91.5 mm SL, Nha Trang, Vietnam. Plectranthias kelloggi azumanus (Jordan & Richardson, 1910): FRLM 50692, 52306, 98.8–91.4 mm SL, Shima, Mie, Japan. Plectranthias sagamiensis (Katayama, 1964): FRLM 7048, 7831, 58.0–53.0 mm SL, Shima, Mie, Japan. Plectranthias yamakawai Yoshino, 1972: FRLM 42846, 42847, 131– 151 mm SL, Yoron I., Kagoshima, Japan. Pseudanthias elongatus (Franz, 1910): FRLM 6617, 6956 *, 11736, 119– 132 mm SL, Shima, Mie, Japan. Pseudanthias pascalus (Jordan & Tanaka, 1927): FRLM 10746, 10747, 119– 111 mm SL, Naha, Okinawa, Japan. Pseudanthias squamipinnis (Peters, 1855): FRLM 45827, 45828, 64.3–71.7, Kumano, Mie, Japan. Sacura margaritacea (Hilgendorf 1879): FRLM 44937, 44938, 49210*, 109–112 mm SL, Shima, Mie, Japan. Selenanthias analis Tanaka, 1918: FRLM 0 6929, 44911, 104 mm SL, Shima, Mie, Japan. Serraninae (Serranidae) — Chelidoperca hirundinacea (Valenciennes in Cuvier & Valenciennes 1831): FRLM 7818, 139 mm SL, Mie, Japan; FRLM 47416, 137 mm SL, Tosa Bay, Mimase, Kochi, Japan. Chelidoperca pleurospila (Günther, 1880): FRLM 34624, 41021, 115– 122 mm SL, Shima, Mie, Japan. Epinephelinae (Serranidae) — Epinephelus areolatus (Forsskål 1775): FRLM 45823 *, 187 mm SL, Kumano, Mie, Japan. Grammistes sexlineatus (Thunberg 1792): FRLM 34732, 76.0 mm SL, Yaku I., Kagoshima., Japan; FRLM 39892, 87.2 mm SL, Kushimoto, Wakayama, Japan. Liopropoma japonicum (Doderlein in Steindachner & Döderlein, 1883): FRLM 10293, 46470, 169– 188 mm SL, Shima, Mie, Japan. Liopropoma latifasciatum (Tanaka, 1922): FRLM 34845 *, 34890, 125– 129 mm SL, Bitung, North Sulawesi, Indonesia. Lutjanidae — Aphareus rutilans Cuvier in Cuvier & Valenciennes, 1830: FRLM 35534 *, 183.0 mm SL, Owase, Mie, Japan. Lutjanus bengalensis (Bloch 1790): FRLM 33773, 33801, 22836, 118– 123 mm SL, Owase, Mie, Japan. Lutjanus fulvus (Forster in Bloch & Schneider, 1801), FRLM 28898 *, 149.0 mm SL, Iriomote I., Okinawa, Japan. Lutjanus kasmira (Forsskål, 1775): FRLM 28484, 156.0 mm SL, Hahajima I., Ogasawara Is., Japan; FRLM 33016, 160 mm SL, Iriomote I., Okinawa, Japan. Asterisks indicate the specimens for observation of cranium. Dinopercidae — Dinoperca petersi (Day, 1875): FRLM 27648, 271 mm SL, Durban, South Africa.