Opistognathus solorensis Bleeker

Smith-Vaniz, William F., 2016, Opistognathus ensiferus, a new species of jawfish (Opistognathidae) from the Gulf of Mannar, India, with redescription of O. solorensis Bleeker, Zootaxa 4196 (2), pp. 278-288 : 283-287

Opistognathus solorensis Bleeker

( Figures 2 A, 3A, 5–10; Tables 1‒4)

Opistognathus solorensis Bleeker, 1853:81 (original description, Lawajong, [= Solor Island, Indonesia]; Bleeker, 1874:471, pl.9, fig. 3 (description; Solor, Amboina, Goram ); Bleeker, 1983, pl. 421, color fig. 1; Allen and Adrim, 2003:34 (listed); Allen et al., 2003:298 unnumbered color photograph (Solor jawfish, brief description, habitat, distribution); Allen, 2009:62, unnumbered color photograph (same as preceding); Allen and Erdmann, 2012:355, unnumbered color photo (brief description, habitat, distribution).

Diagnosis. A species of Opistognathus with an elongate supramaxilla and maxilla with flexible lamina posteriorly, widest before end and sword-shaped in adult males; inner lining of upper jaw and adjacent membranes with two black stripes and area above and below esophageal opening darkly pigmented ( Fig. 3 A); spinous dorsal fin with 1 or 2 black spots or blotches anteriorly; dorsal fin XI, 13–15 (typically 14); anal fin III, 14; lateral-line terminus ends below dorsal-fin segmented rays 1–4.

Description. Dorsal fin XI (rarely X),13‒15 (typically 14). Anal fin III,14. Total pectoral-fin rays 37–40 (except 34 in single Taiwanese specimen). Caudal fin: procurrent rays 4–6+4‒5, segmented rays 8+8, middle 12– 14 (typically 14) branched, total elements 24–27; hypural 5 absent. Vertebrae: 10+18 (rarely 10+19); last rib on vertebra 10; epineurals 11–13. Supraneural bones 1. Gill rakers 9–13+17–20 = 27–33.

Scales absent on head, nape, area above lateral line, pectoral-fin base and breast; belly squamation varying from completely scaly or anterior 1/4 naked. Body oblique scale rows about 58–69 (except 53 in single specimen from Guimaras Island, Philippines). Lateral line ends below verticals between 1st to 4th segmented dorsal-fin rays. Lateral line pores numerous, arranged in multiple series above and below embedded lateral-line tubes. Cephalic sensory pores numerous ( Fig. 2 B), completely covering most of head, including all of predorsal area except a small area immediately adjacent to dorsal-fin origin; mandibular pore positions 1–2 with relatively large, single pores, 3rd position with 1 or 2 pores, 4th with 2–4 pores, and 5th with 2–12 pores. Pores more numerous in larger specimens.

Anterior nostril about mid-way between posterior nostril and dorsal margin of upper lip, consisting of a short tube with posterior rim longer that when depressed does not reach or just reaches margin of posterior nostril; height of tube shorter than to about equal maximum of diameter of posterior nostril. Dorsal fin moderately low anteriorly, with profile relatively uniform without any change in fin height at junction of spinous and segmented rays. Dorsalfin spines relatively slender and slightly curved distally, with flexible tips; all segmented dorsal- and anal-fin rays branched distally. Outermost segmented pelvic-fin ray not tightly bound to adjacent ray, interradial membrane incised distally. Posterior margin of preopercle indistinct without a free margin. No papillae on inner surface of lips. Fifth cranial nerve passes under A1β branch of adductor mandibulae.

Upper jaw sexually dimorphic (longer in adult males) and extending 1.1 to 2.4 eye diameters behind posterior margin of orbit; maxilla widest before end and scimitar-shaped, with flexible lamina posteriorly; supramaxilla moderately large, elongate and subterminally positioned. Jaws subequal, lower slightly included. Premaxilla with an outer row of moderately large, sharply pointed, conical teeth, those near posterior end of jaw noticeably smaller and more closely spaced; 2 or 3 irregular inner rows of much smaller conical teeth anteriorly, several slightly enlarged adjacent to premaxillary symphysis. Dentary with an outer row of conical teeth, those on posterior half of dentary largest and slightly hooked inward; anterior teeth blunter and with 2 or 3 inner rows of slightly smaller, conical teeth, those on innermost row canted backwards. Vomerine teeth absent. Infraorbital bones tubular with wide openings for sensory canals, 3rd infraorbital relatively robust with moderate suborbital shelf.

The following measurements are based on 15 males, 34.3–74.5 mm SL, and 15 females (in parentheses), 36.2– 61.2 SL, as percent of SL: predorsal length 27.8–32.0 (28.5–34.2); preanal length 49.8–55.2 (52.3–62.7); dorsal-fin base 66.2–72.5 (66.0–77.4); anal-fin base 37.1–41.0 (33.8–40.3); pelvic fin length 20.0–25.2 (18.8–26.7); caudal fin length 19.2–22.4 (19.0–24.8); depth at anal-fin origin 15.0–18.5 (15.2–19.2); head length 29.4–34.5 (31.2– 38.7); postorbital-head length 19.9–23.8 (19.7–27.0); upper jaw length 21.1–29.4 (20.9–25.5); postorbital-jaw length 11.2–19.1 (9.4–15.2); orbit diameter 7.4–10.2 (8.2–9.8). As percent of head length: postorbital-head length 60.7–79.0 (60.9–69.9); upper jaw length 67.3–90.5 (64.1–70.3); postorbital-jaw length 36.7–60.0 (28.7–40.6); orbit diameter 23.1–30.9 (23.3–30.0).

Color pattern in alcohol ( Figs. 5‒7 ): Complex pattern of brown stripes and bands, and white spots or blotches; dorsal fin with series brown and white spots arranged in rows, and with one or two pale edged black spots anteriorly, the first between spines 1–4 or 2–5; dorsal and anal fins with series of small brown and white spots; dorsal fin usually with a series of 6–8 dark basal blotches and anal fin with a submarginal narrow dark stripe. Inner lining of upper jaw and adjacent membranes with two black stripes; area above and below esophageal opening darkly pigmented and continuous between innermost pair of upper pharyngeal tooth plates.

In life, color pattern as in preserved specimens, except pale inner areas of maxilla yellow. Occasional specimens almost entirely yellow ( Figs. 8‒9 ); Opistognathus variabilis is the only other species that is known to rarely have a yellow morph. Bleeker's original color drawing of Opistognathus solorensis ( Fig. 10 ) agrees reasonably well with the above description of typical specimens. Bleeker reported the number of blackish blotches in the spinous dorsal fin as 1–3. None of the specimens listed below have more than two blotches in the spinous dorsal fin, suggesting that Bleeker's count of three was erroneous. There is usually only a single blotch in the spinous dorsal fin but specimens from the Molucca Islands and Great Tobea Island, Sulawesi, have two dark blotches, the first between spines 2–4 or 2–5 and another slightly smaller blotch centered on the next posterior spine.

Distribution. Indo-West Pacific. Known from Taiwan, Brunei, Philippines, Indonesia, Timor Leste, Paupa New Guinea and Palau ( Fig. 4 ), in 0.5– 30 m.

Etymology. Named for the type locality, Solor, a small island off the southeast end of Flores Island (8°45'S, 123°30'E), Indonesia.

Type material. No specimens are available from the Lawajong (= Solor) type locality, and the eight specimens subsequently cited by Bleeker (1874:472), including the holotype, are not extant. In the 1879 auction catalogue of Bleeker's collections (see Hubrecht, 1973:16), O. solorensis (Groupe III, no. 129) is marked with an asterisk indicating that these specimens were then in a bad state of preservation. According to M.J.P. van Oijen (in litt., 10 Jan. 1991), current curator of fishes at the RMNH in Leiden, neither he or former curator M. Boeseman were able to locate any Bleeker specimens of O. solorensis . A copy of the catalogue of Dr. C.M.L. Popta (curator from 1898– 1928) includes a notation that the specimens were lost. In order to stabilize the nomenclatural application of the name Opistognathus solorensis Bleeker, I herein designate as the neotype RMNH 31660 (formerly USNM 210929), 62.3 mm SL, male, Indonesia, Banda Sea, Saparua, tidepool at Kulur (Kolor), V.G. Springer, 20 January 1973.

Other material examined. 102 specimens, 14–74.5 mm SL. Taiwan: SAIAB 27653 (1, 64), W. coast of Kenting National Park, off Wanlitong, 10– 12 m . Brunei: WAM P.33117–001 (4, 24–48) , Brunei Patches, 5°0.69'N, 114°42.147'E, 12 m ; WAM P.33035–002 (4, 31–47), Abana Rock , 5°06'N, 115°04'E, 12– 14 m . Philippines: BPBM 26559 (1, 47), Luzon , Batanagas, Caban Island, 13°40'45"N, 120°50'30"E 30 m ; USNM 339205 (1, 43), Luzon , Pangasinan Prov., off Bolinao, Balingasay Reef, 16°20'N, 119°52'E, 12–33.5 m ; USNM 339208 (2, 42–47), same locality as preceding, 21–24m ; FMNH 118282 (1, 33), Palawan Prov., Tara Island, off NE coast of Busuanga , 12°18.90'N, 120°20.92'E, 22–25 m ; USNM 396244 (16, 14–45), Palawan Prov., NW coast of Busuanga , near Illultuk Bay, off W side Elet Island, 12°15.16'N, 119°51.01'E ; USNM 339206 , (1, 45), Panay , Iloilo Prov., Sicogon Is., 11°25'20"N, 123°14'45"E, 12–14.5 m ; FMNH 118285 (11, 24–41), Palawan Prov., off western Busuanga , West Nalaut Islnad, 12°2.7'N, 119°47.58'E, 10–15 m ; FMNH 118284 (4, 27–41), Palawan Prov., SW of Saddle Rock off SW Culion Island, 11°45.95'N, 119°53.22'E, 15–35 m ; FMNH 118283 (1, 36), Palawan Prov., Culion Island, 11°40.55'N, 119°58.48'E, 24–26 m ; USNM 396238 (2, 36–45), Palawan Prov., SE tip of Galoc Island, 11°56.33'N, 119°49.78'E, 10–20 m ; WAM P. 32884–005 (1, 36), Palawan Prov., Bacuit Bay , Pangulasian Island, 11°7.036'N, 119°19.86'E, 18 m ; USNM 339207 (1, 39), Guimaras Island, 10°28'25"N, 122°28'E, 14–20 m ; ANSP 142960 (20, 25–51.5), Palawan Prov., Bararin Isand (Cuyo Is.), 10°52'42"N, 120°56'44"E, 0– 17 m . Indonesia: WAM P.31558– 0 0 4 (1, 65), Raja Ampat Is., Kri Island , 0°33'S, 130°41'E, 0.5 m ; USNM 122419 (1, 43), Sulawesi, Great Tobea Is., 4°33'S, 122°42'E, tide pool; AMS I.18469–086 (1, 68), Banda Sea, Ceram, Marsegoe Bay ; USNM 210929 (8, 35– 74.5), Saparua Island, Kulur ; USNM 216404 (1, 60), Great Banda Island ; USNM 210949 , (1, 73), Nusa Laut Island, 3°40'S, 128°47'E ; USNM 220948 (2, 57–61), presumably Banda Sea (several specimens of blenniids from this lot are referable to W. H. Longley notes made on Banda specimens) ; WAM P.33896–001 (1, 20), Komodo Is., Rinca I., 8°37.693'S, 119°42.499'E, 14– 15 m. Timor Leste : WAM P.33753–001 (10, 40.9–67.6), Timor Leste, Manatuto, 8°30.826'S, 126°4.157'E, 0.3–1.0 m . Papua new Guinea: WAM P.30623–006 (1, 53.5) , Madang, 5°9'S, 145°50'E . Palau: ROM 77505 (5, 32–49), Ngeruketabel Island , 7°15'52"N, 134°28'17.3"E, 24–26.5 m .

Figures

FIGURE 2. Cephalic sensory pores in two species of Opistognathus: A, O. ensiferus n. sp., holotype and B, O. solorensis, WAM P. 33117 – 001, male, 48 mm SL, Brunei.

FIGURE 3. Diagrammatic illustrations of oral pigmentation in two species of Opistognathus: A, O. solorensis and B, O. verecundus.

FIGURE 4. Distribution of Opistognathus solorensis species group. Collections from closely adjacent localities are represented by single symbols.

FIGURE 5. Opistognathus solorensis, USNM 210949, male, 72.9 mm SL, Nusa Laut Island, Molucca Islands. Drawn by Jack R. Schroeder.

FIGURE 6. Opistognathus solorensis, WAM P. 33753 – 001, male 57.3 mm SL, Timor Leste. Photograph by Sandra J. Raredon.

FIGURE 7. Opistognathus solorensis, WAM P. 33753 – 001, female 54.5 mm SL, Timor Leste. Photograph by Sandra J. Raredon.

FIGURE 8. Opistognathus solorensis, Lembeh Strait, Sulawesi. Photograph by Ned DeLoach.

FIGURE 9. Opistognathus solorensis, showing variation in coloration, ROM 77505, Ngeruketabel Island, Palau: (A) 31.9 mm SL, male, (B) 48.8 mm SL, female, (C) 42.2 mm female. Photographs by R. Winterbottom.

FIGURE 10. Opistognathus solorensis Bleeker original illustration (after Bleeker, 1983, pl. 421, fig. 1).