Neomerinthe pallidimacula ( Fowler, 1938 )

Motomura, Hiroyuki, Causse, Romain & Béarez, Philippe, 2016, Validity of a poorly known western Pacific scorpionfish (Scorpaenidae), Neomerinthe pallidimacula (Fowler, 1938), Cybium 40 (2), pp. 109-113 : 110-112

Neomerinthe pallidimacula ( Fowler, 1938) [New English name: Three-striped Scorpionfish]

( Fig. 1 )

Material examined

MNHN 2001-2850 , 70.2 mm SL, west of Wallis and Futuna Islands , 14°19’04”S, 178°04’04”E, 245-400 m , RV Alis , 11 May 1992 ; USNM 98889 , holotype of Scorpaena pallidimacula , 76.0 mm SL, around Pujiada Bay , Uanivan Island, Philippines, 06°50’45”N, 126°14’38”E, 215 fathoms (ca. 393.5 m) , RV Albatross , 14 May 1908 .

Diagnosis

A species of Indo-Pacific Neomerinthe with the following combination of characters: lateral lacrimal spine absent; ventrally directed anterior lacrimal spine; 3 suborbital spines; indistinct median ridge on lateral surface of maxilla; posterior margin of maxilla reaching to vertical through posterior margin of orbit; well-developed symphysial knob; second preopercular spine absent; well-developed upper posttemporal spine; slit behind fourth gill arch; 18-20 pectoral-fin rays; pectoral-fin membranes between middle and lower rays deeply incised; 44-45 scale rows in longitudinal series; 3 slightly curved brownish white or white stripes on lateral surface of trunk in preserved specimens.

Description

Data for the holotype are presented first, followed by the second specimen data (if different) in parentheses. Dorsal-fin rays XII, 10 (9). Anal-fin rays III, 5. Pelvic-fin rays I, 5. Pectoral-fin rays 20 (18) on both sides. Longitudinal scale rows 44 (45). Pored lateral-line scales 22 (23). Scale rows between origin of sixth dorsal-fin spine and lateral line 5. Scale rows between origin of last dorsal-fin spine and lateral line 5. Scale rows above lateral line 5 (6), below lateral line 12. Gill rakers on upper limb 5 (6), lower limb 10 (13), including 2 (4) rakers on hypobranchial; total rakers 15 (20). Branchiostegal rays 7.

The following morphometrics are expressed as percentage of SL: Body depth 36.8 (40.7); body width 20.0 (22.9); head length 48.7 (53.6); snout length 11.2 (11.9); orbit diameter 15.5 (15.7); interorbital width at middle of eye 5.0 (6.0); interorbital width between preocular spine bases 6.2 (6.4); head width 15.9 (16.2); upper-jaw length 25.0 (24.6); maxillary depth 8.2 (7.8); suborbital space 2.2 (3.6); postorbital length 24.6 (26.5); distance between tips of opercular spines 8.3 (7.5); predorsal-fin length 43.8 (46.0); preanal-fin length 75.3 (74.2); prepelvic-fin length 38.8 (39.3); first dorsal-fin spine length 7.9 (10.0); second dorsal-fin spine length – (16.5); third dorsal-fin spine length – (19.1); fourth dorsal-fin spine length 19.9 (19.7); fifth dorsal-fin spine length – (19.1); eleventh dorsal-fin spine length 5.7 (8.5); twelfth dorsal-fin spine length – (15.1); first anal-fin spine length 6.1 (8.5); second anal-fin spine length 18.7 (24.4); third anal-fin spine length 15.5 (19.4); longest anal-fin soft ray length 19.2 (22.9); longest pectoral-fin ray length – (37.6); pelvic-fin spine length 16.4 (17.9); longest pelvic-fin soft ray length 23.3 (29.2); caudal-fin length – (28.8); caudal-peduncle length 15.5 (15.1); caudal-peduncle depth 11.3 (10.8).

Membrane of spinous portion of dorsal fin moderately notched; spine damaged in holotype (third dorsal-fin spine longest). Second anal-fin spine longest; all soft rays branched; first soft ray longest; posterior branch of last soft ray not joined by membrane to caudal peduncle. Tips of all pectoral-fin rays damaged in holotype (upper 3 and lower 9 rays unbranched, remaining rays branched; posterior margin of pectoral fin bilobed, twelfth ray longest, its length less than head length; all rays not thickened). All pelvic-fin soft rays branched; second soft ray longest, its length longer than longest anal-fin soft ray; last soft ray joined by membrane to abdomen for one-third of its length.

Body moderately compressed anteriorly, progressively more compressed posteriorly. Nape and anterior body moderately arched. Body depth relatively deep, but less than head length. Supraocular tentacle damaged in holotype (its length subequal to orbit diameter, its tip reaching to nuchal spine when laid back). Posterior lacrimal spine associated with slender, fleshy tentacle, its length subequal to pupil diameter; posterior lacrimal spine tentacle linked posteriorly to head by skin. Short, branched tentacle on posterior edge of low membranous tube associated with anterior nostril; the tentacle extending beyond posterior margin of posterior nostril when laid back. Pectoral-fin axil without skin flaps.

Well-exposed ctenoid scales covering surface of body; body scales not extending onto rays or membranes of fins, except bases of pectoral and caudal fins. Cycloid scales covering pectoral-fin base and anteroventral body. Exposed scales on cheek, behind orbit, opercle, and occiput. Lateral line complete, extending onto base of caudal fin; lateral line sloping slightly downward above posterior tip of opercle. Underside of dentary with three well-developed sensory pores on each side, first pore below origin of anterior lacrimal spine, second pore below posterior lacrimal spine, third pore located on posterior margin of dentary. A pair of small pores behind symphysial knob of lower jaw in ventral view. Gill rakers relatively long with spinous tips, length of longest raker on first gill arch longer than that of gill filaments around angle of gill arch; slit behind fourth gill arch.

Mouth large, oblique, forming an angle of about 20 (15) degrees to horizontal axis of head and body. Posterior margin of maxilla just reaching to vertical through posterior margin of orbit. Indistinct longitudinal median ridge on lateral surface of maxilla. Lower jaw with well-developed symphysial knob. Villiform teeth on upper and lower jaw; tooth band narrowing posteriorly. Villiform teeth on vomer and palatines; width of vomer less than palatine length. Underside of lower jaw without ridges.

Dorsal profile of snout steep, forming an angle of about 70 degrees to horizontal axis of head and body. Nasal spine simple, directed dorsally. Ascending process of premaxilla not intruding into interorbital space. Median interorbital ridge absent. Interorbital ridges poorly developed, separated by relatively shallow channel, beginning posterior to nasal spines and ending at bases of tympanic spines; ridges not conjoined to each other. Interorbital space relatively shallow, about one-tenth of orbit extending above dorsal profile of head. Preocular spine simple, directed dorsally; flattened anteriorly and posteriorly; anterior surface of spine without distinct ridges. Supraocular spine simple, not strongly canted laterally; its length subequal to that of postocular spines. Postocular spine simple, not canted laterally. Tympanic spine simple, not canted laterally, located behind postocular spine. Interorbital, coronal, and pretympanic spines absent. Occipital pit absent, occipital region nearly flat, without distinct transverse ridges in front or rear of occiput. Occiput surrounded laterally only by bases of tympanic and parietal spines. Parietal spine simple. Nuchal spine simple; nuchal and parietal spines joined at base. Postorbital and sphenotic with several tiny spines. Indistinct ridge between tympanic and sphenotic spines. Pterotic spine simple, its base length less than that of parietal spine base. Upper posttemporal spine present. Lower posttemporal spine simple, its base length slightly greater than that of pterotic spine base. Supracleithral spine simple. Cleithral spine flattened, pointed.

Lateral lacrimal spine absent. Anterior tip of anteriorly directed lacrimal ridge embedded. Anterior lacrimal spine simple, directed ventrally, its tip just reaching to (extending slightly beyond) dorsal margin of upper lip. Posterior lacrimal spine simple, directed posteroventrally; posterior lacrimal spines larger than anterior lacrimal spine. Suborbital ridge with three spines; first spine below posterior margin 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 a supplemental preopercular spine on its base; second spine absent; 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.

Origin of first dorsal-fin spine above second (first) pored lateral-line scale. Pectoral fin damaged in holotype (posterior tip of fin reaching to vertical through base of first anal-fin soft ray). Origin of pelvic-fin spine slightly anterior to vertical through origin of first pectoral-fin ray. Posterior tip of depressed pelvic fin extending beyond anus. Origin of first anal-fin spine slightly posterior to vertical through base of last dorsal-fin spine.

Colour of preserved specimens. – Body brown (brownish white) with three slightly curved brownish white (white) stripes on trunk. No black blotches on body or fins.

Remarks

Neomerinthe pallidimacula has been known only from the holotype. Examination of the second specimen of the species from the Wallis and Futuna Islands together with the holotype revealed that N. pallidimacula is a valid species having the following unique characters among the Indo-Pacific species of Neomerinthe : a well-developed symphysial knob (vs. poorly or moderately developed in the latter group of species) and three slightly curved brownish white or white stripes on the lateral surface of the trunk in preserved specimens (vs. stripes usually absent, rarely one or two indistinct stripes present).

In addition, N. pallidimacula has the unique combination of two characters, i.e., absence of the lateral lacrimal and second preopercular spines, whereas other Indo-Pacific congeners exhibit the following three patterns: presence of lateral lacrimal spine but absence of second preopercular spine, absence of lateral lacrimal spine but presence of second preopercular spine, or presence of both lateral lacrimal and second preopercular spines ( Motomura et al., 2011, 2015; this study).

The pectoral-fin membranes between the middle and lower rays of N. pallidimacula are deeply incised, a character also found in Neomerinthe bauchotae Poss & Duhamel, 1991 . However, in addition to the above mentioned unique characters, N. pallidimacula further differs from N. bauchotae in having a slit behind the fourth gill arch (vs. slit absent in the latter), 18-20 pectoral-fin rays (vs. 16-17), well-developed upper posttemporal spine (vs. spine absent), the posterior margin of the maxilla reaching to a vertical through the posterior margin of the orbit (vs. not reaching), and an indistinct median ridge on the lateral surface of the maxilla (ridge absent).

Fowler (1938: fig. 25) illustrated the holotype of Scorpaena pallidimacula showing a large dark blotch on the spinous portion of the dorsal fin and the rounded pectoral fin. However, there was no trace of the blotch on the membrane of the dorsal fin in the holotype and the posterior half of the pectoral fin in the holotype was missing ( Fig. 1A ). The second specimen of N. pallidimacula has a unique shape of the pectoral fin, suggesting that Fowler (1938) illustration of the holotype pectoral fin is probably an error. In addition, Fowler illustration shows two stripes on the trunk although the holotype has three stripes as mentioned above.

The holotype and the second specimen were collected from the Philippines at a depth of around 400 m and the Wallis and Futuna Islands at 245-400 m respectively. This indicates that N. pallidimacula is likely to be widely distributed in deepwater in the western Pacific Ocean .

Acknowledgements. – We are especially grateful to J. Williams, L. Palmer, S. Raredon, and K. Murphy (USNM) for opportunities to examine material and P. Pruvost, Z. Gabsi, and C. Ferrara (MNHN) for their kind help during the first author visits to Paris in 2010-2015, that were supported by the Muséum national d’Histoire naturelle. We greatly appreciated comments on the manuscript by G. Yearsley ( Australia). This study was supported in part by Grants-in-Aid for Scientific Research (A: 26241027, B: 24370041 and C: 23580259 and 26450265) from the Japan Society for the Promotion of Science, Tokyo, Japan (JSPS); the JSPS Asian Core Program, “Establishment of Research and Education Network on Coastal Marine Science in Southeast Asia”; the “Coastal Area Capability Enhancement in Southeast Asia Project” of the Research Institute for Humanity and Nature, Kyoto, Japan; “Establishment of Research and Education Network on Biodiversity and Its Conservation in the Satsunan Islands” project of Kagoshima University adopted by the Ministry of Education, Culture, Sports, Science and Technology, Japan; and the “Biological Properties of Biodiversity Hotspots in Japan ” project of the National Museum of Nature and Science, Tsukuba, Japan.

Figures

Figure 1. - Preserved specimens of Neomerinthe pallidimacula. A: USNM 98889, holotype of Scorpaena pallidimacula, 76.0 mm SL; B: MNHN 2001- 2850, 70.2 mm SL.