Neomerinthe ornithoptera, Matsumoto & Motomura, 2024

Matsumoto, Tatsuya & Motomura, Hiroyuki, 2024, Neomerinthe ornithoptera, a new species of scorpionfish (Teleostei: Scorpaenidae) from the southwestern Pacific Ocean, with a reassessment of the diagnosis for N. pallidimacula (Fowler 1938), Zootaxa 5428 (1), pp. 135-145 : 137-141

Neomerinthe ornithoptera n. sp.

[New English name: Bird Wing Scorpionfish]

Figures 1 , 2 , 3 ; Table 1

Neomerinthe sp. 2 : Motomura et al. 2011: 62 ( Wallis and Futuna Islands).

Neomerinthe pallidimacula (not of Fowler, 1938): Motomura et al. 2016: 111, fig. 1B ( Wallis and Futuna Islands).

Holotype. BPBM 40086 , 68.3 mm SL, outside Suva Harbor , Suva, Viti Levu Island, Fiji, 18°09′36.6″S, 178°23′57.6″E, 340– 360 feet (ca. 103–109 m), R. L. Pyle, J. L. Earle & J. Dituri, 4 Feb. 2002.

Paratypes. 2 specimens. KAUM-I. 190376, 67.0 mm SL, data same as holotype; MNHN 2001–2850 , 70.2 mm SL, west of Futuna Island , Wallis and Futuna Islands, 14°19′04″S, 178°04′04″E, 245–400 m, RV Alis, 11 May 1992 .

Diagnosis. A species of Neomerinthe with the following combination of characters: dorsal-fin rays 9; pectoral-fin rays 18; scale rows in longitudinal series 44 or 45; pored lateral-line scales 23; scale rows above lateral line 6 or 7, below lateral line 12; scale rows between sixth dorsal-fin spine base and lateral line 5; scale rows between last dorsal-fin spine base and lateral line 5; upper gill rakers 6, lower gill rakers 13 [9 or 10 and 3 or 4 on ceratohyal and hypobranchial, respectively], total gill rakers 19; longitudinal ridge on lateral surface of maxilla absent; lateral lacrimal spine absent; suborbital spines 3; second preopercular spine absent; minute slit behind last gill arch; many small cycloid scales on base of pectoral fin and ventral surface of body between isthmus and posterior to pelvic fin; several lower pectoral-fin rays markedly elongated; pectoral-fin ray length 37.6–40.0% of SL; first anal-fin spine length 6.9–8.5% SL; second anal-fin spine length 23.3–25.5% SL; third anal-fin spine length 22.7–23.1% SL; pelvic-fin spine length 17.9–18.1% SL; longest pelvic-fin soft ray length 26.6–29.2% SL; preserved specimens with pale yellowish body and pectoral fins, and indistinct blotches on body above lateral line.

Description. Meristics and morphometrics of N. ornithoptera sp. nov. given in Table 1 . Data for holotype presented first, followed by other specimen data (if different) in parentheses.

Dorsal fin with 12 spines. Origin of first dorsal-fin spine just above lower posttemporal spine tip. Fourth dorsal-fin spine longest, fourth to eleventh spines progressively shorter; membrane of spinous portion moderately incised; all soft rays branched; third soft ray longest; posterior margin of soft-rayed portion of dorsal fin rounded; posterior branch of last soft ray strongly joined by membrane to caudal peduncle. Anal fin with 3 spines and 5 soft rays. Origin of first anal-fin spine posterior to origin of first dorsal-fin ray; first anal-fin spine shortest, second spine longest; all soft rays branched; second soft ray longest; posterior branch of last soft ray not joined by membrane to caudal peduncle; origin of last soft ray slightly anterior to origin of eighth dorsal-fin soft ray. Pectoral fin with 3 (or 2) uppermost and 8 (9 or 10) lowermost rays unbranched, remaining 5 (6 or 8) rays branched; twelfth (or thirteenth) ray longest; lower unbranched rays not thickened; posterior margin of pectoral fin bilobed. Pelvic fin with 1 spine and 5 soft rays. Origin of pelvic-fin spine slightly anterior to and below level of first dorsal-fin spine base; all soft rays branched; second soft ray longest; last soft ray joined by membrane to abdomen for less than half its length. Gill rakers relatively short, spinous; length of longest raker on first gill arch shorter than that of gill filaments around angle of gill arch.

Dorsal profile of snout gentle, forming angle of ca. 50 degrees to horizontal axis of head and body. Body moderately compressed anteriorly, progressively more compressed posteriorly. Body relatively deep, deepest at pelvic-fin base. Posterior margin of opercular membrane reaching vertical through fourth dorsal-fin spine base. Short, broad tentacle, with several short branches distally, on posterior edge of low membranous tube associated with anterior nostril. Tentacles on preocular, supraocular, parietal, anterior lacrimal, posterior lacrimal and some preopercular spines; those on supraocular and posterior lacrimal spines large, others minute. Posterior lacrimal spine tentacle linked posteriorly to head by skin. Tentacles absent on eye membrane, anterior margin of lower snout in anterior view, cheek, maxilla, lips, underside of lower jaw, opercle, mid-interorbital space, occiput, and all fin surfaces. Pectoral-fin axil without skin flaps. Well-exposed ctenoid scales covering posterior half of lateral surface of head, including cheek, behind eye, opercle, and an area surrounded by parietal, nuchal, pterotic and lower posttemporal spines. Well-exposed ctenoid scales on lateral surface of trunk. Exposed ctenoid scales covering entire occiput. Body scales not extending onto rays or membranes of fins, except basally on pectoral and caudal fins. Lateral line sloping steeply downward above anterior half of pectoral fin. Underside of lower jaw with 3 large, well-developed sensory pores on each side, first pore below anterior lacrimal ridge, second pore below tip of anterior lacrimal spine, third pore on posterior margin of dentary; pores larger than anterior nostril diameter. A pair of small pores behind lower jaw symphysial knob in ventral view.

Mouth large, slightly oblique, forming angle of ca. 25 (15–25) degrees to horizontal axis of head and body. Posterior margin of maxilla beyond vertical through posterior margin of pupil, not reaching posterior margin of orbit. longitudinal ridge on lateral surface of maxilla absent. Lower jaw with large (somewhat smaller) symphysial knob. Width of symphysial gap separating premaxillary tooth bands slightly greater than width of each band. Upper jaw with band of short, conical teeth; teeth tips pointed. Tooth band of upper jaw slightly narrower than that of lower jaw. Lower jaw with band of villiform teeth; most teeth shorter than those on upper jaw. Small teeth on vomer and palatines. Underside of lower jaw without ridges.

Nasal spine simple, sharp, conical, directed dorsally, its length shorter than anterior nostril diameter. Ascending process of premaxilla not intruding into interorbital space, its posterior margin extending beyond level of anterior margin of posterior nostril in dorsal view, not extending beyond posterior margin of posterior nostril. Median interorbital ridge absent. Interorbital ridges well developed, separated by moderately deep channel, beginning posterior to nasal spines and ending near tympanic spine base; narrowest distance between ridges directly above anterior margin of pupil. About one-tenth of orbit extending above dorsal profile of head. Preocular spine simple, directed dorsally; tip of spine beyond level with upper margin of pupil in lateral view, flattened anteriorly and posteriorly, anterior surface without median vertical ridge. Supraocular spine simple, its length slightly less than that of postocular spines. Postocular spine simple, not strongly canted laterally; base wider than tympanic spine base, not joined to interorbital ridge or tympanic spine base. Tympanic spine simple, strongly pointed, directed dorsoposteriorly, with narrow base; base not joined to interorbital ridge or parietal spine base. Coronal spine absent. Occiput nearly flat, slightly convex centrally, lacking transverse ridge anteriorly or posteriorly to occiput. Occiput surrounded laterally by postocular, tympanic and parietal spines; no ridges on lateral aspects of occiput in dorsal view. Parietal spine simple, its base length greater than length of lower posttemporal spine base. Nuchal spine simple, well developed; its tip strongly pointed; nuchal and parietal spines joined at base. Sphenotic with several small spines. Postorbital without spines. Pterotic spine simple, located below parietal spine. No distinct ridge on area surrounded by parietal, nuchal, pterotic and lower posttemporal spines. Upper posttemporal spine simple, pointed, small, directed dorsoposteriorly, its length much less than that of lower posttemporal spine. Lower posttemporal spine simple. Supracleithral spine simple, strongly pointed. Cleithral spine flattened, pointed, without median ridge.

Anterior lacrimal spine simple, directed ventrally, its tip just reaching (extending slightly beyond) dorsal margin of upper lip. Posterior lacrimal spine simple, directed posteroventrally, larger than anterior lacrimal spine. Suborbital ridge with 3 spines; first spine below middle of pupil; second spine below posterior margin of orbit; third spine behind orbit at end of ridge. Space between ventral margin of eye and suborbital ridge relatively narrow. Suborbital pit absent. Preopercle with four spines; uppermost spine largest, with one supplemental preopercular spine on base; third to fifth spines triangular. Preopercle (between uppermost preopercular spine and upper end of preopercle) without serrae or spines. Upper opercular spine simple, without distinct median ridge. Lower opercular spine simple, with distinct median ridge. Space between upper and lower opercular spines without ridges. Posterior tips of upper and lower opercular spines not reaching opercular margin.

Color in preserved specimens ( Fig. 1 ). Body and head uniformly pale yellowish with indistinct blackish blotches dorsally ( Fig. 1 ). All fins semi-translucent whitish, without blotches ( Fig. 1 ).

Etymology. The specific name ornithoptera is a combination of the Greek words “ornith” (meaning bird) and “ptera” (wing), given in reference to the pectoral fin shape, reminiscent of a bird’s wing.

Distribution. Currently known from the Wallis and Futuna Islands and Fiji, southwestern Pacific Ocean.

Remarks. The new species can be readily distinguished from all other Indo-Pacific congeners, except N. pallidimacula (currently known only from the holotype from the Philippines), by the lack of lateral lacrimal and second preopercular spines [Note: Neomerinthe kaufmani ( Herre 1952) and Neomerinthe megalepis ( Fowler 1938) , both lacking a second preopercle spine, rarely lack the lateral lacrimal spine ( Matsumoto & Motomura 2023), and a specimen of Neomerinthe bucephalus ( Alcock 1896) (SIO 80-223, paratype, 99.4 mm SL) was confirmed here as lacking both a lateral lacrimal and second preopercular spines]. Because of their similarity in these characters, N. ornithoptera has been previously reported as N. pallidimacula (see Motomura et al. 2016), but the former, having 18 pectoral-fin rays, differs from N. pallidimacula (20 pectoral-fin rays) ( Table 1 ). In fact, the number of pectoral-fin rays shows little intraspecific variation in Indo-Pacific species of Neomerinthe , usually being within one either side of the modal number in each [e.g., none of 14, 57, 90, 27, and 29 specimens of Neomerinthe bauchotae Poss & Duhamel 1991 , Neomerinthe erostris ( Alcock 1896) , Neomerinthe ignea Matsumoto, Muto & Motomura 2023 , Neomerinthe naevosa Motomura, Béarez & Causse 2011 , and Neomerinthe rufescens ( Gilbert 1905) , respectively, varied by more than one ray from the modal number ( Poss & Duhamel 1991; Motomura et al. 2011; Matsumoto et al. 2023; this study), and only 2 of 177 specimens of Neomerinthe amplisquamiceps ( Fowler 1938) , N. bucephalus , Neomerinthe harenartis Matsumoto & Motomura 2023 , N. kaufmani and N. megalepis varied by two rays from the modal number ( Matsumoto & Motomura 2023)]. In addition, the new species differs from N. pallidimacula in having 23 pored lateral line scales (vs. 22 in N. pallidimacula ), 6 or 7 scale rows above the lateral line (vs. 5), 6 upper gill rakers (vs. 5), 13 lower gill rakers (vs. 10), first anal-fin spine length 6.9–8.5% of SL (vs. 6.1% of SL), second anal-fin spine length 23.3–25.5% of SL (vs. 18.7% of SL), third anal-fin spine length 17.6–19.4% of SL (vs. 15.5% of SL), pelvic-fin spine length 17.9–18.1% of SL(vs. 16.4% of SL), and longest pelvic-fin soft ray length 26.6–29.2% of SL (vs. 23.3% of SL).

The new species is also characterized by significantly extended lower pectoral-fin rays ( Fig. 3A ), which distinguishes it from all Indo-Pacific species, except N. pallidimacula so far as is known (damage to the pectoral fins of the holotype of N. pallidimacula prevented an assessment of that character). The posterior margins of the pectoral fins in N. amplisquamiceps , N. bucephalus , N. erostris , N. harenartis , N. ignea , N. kaufmani , and N. megalepis are all rounded, with the lower rays not extended ( Fig. 3B ), providing further discrimination of the new species from individuals of N. bucephalus , N. kaufmani , and N. megalepis lacking lateral lacrimal and second preopercular spines. Although other valid Indo-Pacific species, N. bauchotae , N. naevosa , and N. rufescens , have slightly extended lower pectoral-fin rays ( Poss & Duhamel 1991; Motomura et al. 2011; this study), the condition in N. ornithoptera is more strongly developed [longest pectoral-fin ray length 37.6–40.0% of SL in N. ornithoptera (3 specimens, 67.0– 70.2 mm SL), vs. 29–37% of SL in N. bauchotae (14 specimens, 26.9–79.8 mm SL; data from Poss & Duhamel 1991), 29.5–35.0% of SL in N. naevosa (27 specimens, 18.4–67.8 mm SL; data from Motomura et al. 2011), and 27.9– 34.9% of SL in N. rufescens (29 specimens, 28.2–82.7 mm SL; this study)].

Figures

FIGURE 1. Preserved specimens of Neomerinthe ornithoptera sp. nov. from Fiji. A BPBM 40086, holotype, 68.3 mm SL; B KAUM-I. 190376, paratype, 67.0 mm SL.

FIGURE 2. Lateral view of head of Neomerinthe ornithoptera sp. nov. BPBM 40086, holotype, 68.3 mm SL. Shaded area indicates area covered with exposed scales.

FIGURE 3. Pectoral fin shape in species of Neomerinthe. A, several lower pectoral-fin rays markedly elongated (Neomerinthe ornithoptera sp. nov., BPBM 40086, holotype, 68.3 mm SL); B, lower pectoral-fin rays not elongated (Neomerinthe bucephalus, NMMB 8641, 132.8 mm SL).