Symphurus maculopinnis Munroe, Tyler & Tunnicliffe, 2011, new species

Field: Agricultural and Biological Sciences (Life Sciences)

Symphurus maculopinnis, new species Figures 1–7; Table 1 Symphurus species B. Tunnicliffe et al. 2010:4 (species recognition; bathymetric and ecological notes; genetic sequence data; distribution, abundance; color photographs). Holotype. USNM 398820, female, 84.4 mm SL, collected on Volcano–19 near Marker 40, Tonga Arc (24°48.439'S, 177°0.009'W), West Pacific Ocean, 561 m, collected with hand-held net (Sample Number R1048– 12) by ROV ROPOS directed by Anna Metaxas, 7 May 2007. Diagnosis. Symphurus maculopinnis is distinguished from all other species of Symphurus by the combination of a 1–2–2–2–1 ID pattern, 14 caudal-fin rays, 3+6 abdominal vertebrae, 49 total vertebrae, about 89 scales in a longitudinal row, 92 dorsal-fin rays, 77 anal-fin rays, a blunt squarish snout, blind-side lower jaw with thick lip with conspicuous plicae, and by conspicuous ocellated (sometimes partially) black spots on the posterior dorsal and anal fins. Description. Morphological description based entirely on holotype (adult female, 84.4 mm SL; Figs. 1–5). A medium-sized species of Symphurus measuring to at least 100 mm SL [based on photographed specimens in Tunnicliffe et al. (2010)]. ID pattern 1–2–2–2–1 (Figs. 3–4). Caudal-fin rays 14. Dorsal-fin rays 92. Anal-fin rays 76 (+1 fin ray missing). Pelvic-fin rays 4; posteriormost pelvic-ray connected to first anal-fin ray by delicate membrane. Total vertebrae 49; abdominal vertebrae 9 (3+6) (Fig. 4). Hypurals 5. Longitudinal scale rows about 89. Scale rows on head posterior to lower orbit 21. Transverse scale rows 45. Morphometrics (expressed as percentages of SL or HL; Table 1). Body moderately elongate (Fig. 2) with greatest body depth (29.6% SL) located in its anterior third (between anal-fin rays 10–25) and with gradual posterior taper. Preanal length slightly smaller than body depth. Head long, moderately wide, with squarish snout (Figs. 2 A, 5); head length (21.6% SL) less than head width (25.6% SL; HW/HL = 1.20). Lower head lobe (12.7% SL) narrower than upper head lobe (16.2% SL); lower head lobe width less than postorbital length. Snout relatively broad with squarish anterior profile; snout length 18.1% HL; snout slightly longer than eye diameter. Dermal papillae conspicuously present on both ocular and blind sides of snout and head, but more numerous on blind-side head (Figs. 5 A–B). Ocular-side snout and head with several short, vertical rows of dermal papillae as well as other dermal papillae not arranged in obvious rows; ocular-side anterior head region dorsal to eyes with five, short, vertical rows of dermal papillae; anterior head region posterior to eyes with single, longer, horizontal row of dermal papillae; a single, short, vertical row of dermal papillae ventral to mid-region of lower eye; cheek region (ventral to lower jaw) with five, short, vertical rows of dermal papillae (Fig. 5 A). Blind-side head and snout (Figs. 5 B) with numerous, conspicuous, vertical and horizontal rows, sometimes interconnected, of dermal papillae extending nearly to ventro-posterior margin of opercle. Ocular-side anterior naris tubular, elongate; just reaching anterior margin of lower eye when depressed posteriorly. Posterior ocular-side naris a short, wide, tubular opening located nearly at vertical through anterior margin of pupil of lower eye. Blind-side anterior naris a short, slender, unpigmented tube located anterior to vertical through mid-jaw and barely perceptible among dense patch of dermal papillae. Blind-side posterior naris a short, posteriorly-directed tube located at posterior margin of dense patch of dermal papillae dorsal to horizontal through base of anterior blind-side nostril. Posterior margin of ocular-side maxilla at vertical through anterior region of pupil of lower eye. Ocular-side lower jaw without fleshy ridge. Blindside lower jaw with thick lip with numerous plicae. Chin depth (20.3% HL) slightly greater than snout length (18.1% HL). Lower eye large (16.5% HL); eyes slightly subequal in position, anterior margin of lower eye at point between verticals through anterior margin of upper eye and anterior margin of pupil of upper eye. Eyes separated by narrow interorbital space about 1–2 scales wide; dorsal aspects of eyes with 3–4 small, ctenoid scales; also with several rows of small ctenoid scales in interorbital space anteriorly. Pupillary operculum absent. Dorsal-fin origin at vertical through anterior margin of pupil of upper eye; predorsal distance 21.9% HL. Postorbital length 13.5% SL. Lower lobe of opercle (40.1% HL) twice as wide as upper opercular lobe (18.7% HL) and with its posterior margin extending noticeably further posteriorly than margin of upper opercular lobe. Both sides of dorsal- and anal-fin rays without scales. Distal tips of most dorsal- and anal-fin rays free from interradial membranes. Caudal fin short (12.9% SL), pointed, with middle fin rays slightly longer than others; basal halves on both sides of caudal fin with several rows of small, ctenoid scales. Ocular-side dentary and maxilla with few teeth on their anterior regions. Blind-side dentary with 2–3 rows of well-developed teeth anteriorly expanding to several rows posteriorly; blind-side premaxilla with 2 rows of welldeveloped teeth curving slightly inwards. Scales moderately large; ctenoid on both sides of body. Live color (Figs. 1; 6–7; based on the holotype and other specimens photographed or videographed in situ at ~ 433–561 m on Volcano–19 from the ROV ROPOS; video edited by Jonathan Rose). Ocular-side head and body grayish-green to light brown and overlain with numerous, irregular, dark-brown blotches of various sizes; also with several incomplete, wide (5–7 scale rows), darker crossbands in midbody region and one complete crossband on caudal 1/4th of body; also with several smaller (2–4 scales wide), irregular white markings scattered over body surface, the largest of which overlies the dorsoanterior abdomen; and with two darker patches– one dorsal to pelvic fin on dorsoanterior abdomen and another situated at ventroposterior margin of abdomen. Dorsal and anal fins each with a conspicuous, intense, ocellated (sometimes partially) black spot on their posteriormost rays (about the posteriormost 6–7 rays based on preserved specimen). Sometimes, black spots completely ocellated by white ring; otherwise, black spot only partially surrounded by one or two much smaller, irregular, white spots situated around its outer periphery. White pigment of dorsal-fin ocellus frequently not completely surrounding black spot near body nor as intense as ocellated ring and spots surrounding dark spot on anal fin. Dorsal and anal fins also with alternating series of lighter and darker blotches (about 4–6 fin-rays wide) throughout nearly entire length of fins. Dorsal-fin rays in anteriormost part of fin with distal thirds bright white and proximal two-thirds darker. Dorsal-fin rays in remainder of fin, and especially in more posterior blotches, more darkly pigmented over entire length of fin rays and also on fin membrane compared with those in blotches on anterior region of fin. Anal fin also with alternating series of lighter (some bright white) and darker blotches (about 4– 6 rays in each series) throughout length of fin to just before black spot on posteriormost fin rays. Anal-fin rays throughout entire fin pigmented over most of their lengths. Anteriormost anal-fin rays nearly entirely white, contrasting sharply to more heavily pigmented darker rays in remainder of fin. Anal-fin membrane in anterior region of fin pigmented only on its basal half, membrane in remainder of anal fin, especially that in dark blotches in posterior third of fin, more heavily pigmented nearly to its distal margin. Caudal fin dusky with several rays partially streaked with white and with several small whitish spots also on caudal-fin base. Pelvic-fin rays white throughout their lengths, in stark contrast to body color, especially contrasting against dark blotch on nearby abdomen. Color in alcohol (Figs. 2, 5; based only on holotype). Ocular-side background pigmentation uniformly medium dark brown with several diffuse, irregular, darker areas; region overlying abdomen dark, brownish-black (Fig. 2 A). Ocular-side head and body scales with posterior halves of exposed region more darkly pigmented than anterior halves of exposed portions. Head coloration similar to that on body, except posterior margin of opercle outlined in black (Fig. 5 A). Snout nearly to distal tip with similar pigment as that on rest of head; distalmost snout region lighter than more posterior regions. Ocular-side lips dark black, except posteriormost parts of upper and lower lips lighter brown. Ocular-side anterior nostril black for most of its length; distalmost tip whitish. Ocular-side inner opercular lining white, ventral half with several faint melanophores; inner lining of blind-side opercle white. Isthmus on both sides with small melanophores, more concentrated on ocular-side isthmus than on blind-side counterpart. Blind-side background coloration of head and body uniformly whitish except for dark, bluish-black abdomen (Figs. 2 B, 5B). Dorsal and ventral margins of blind-side head (Fig. 5 B) also with numerous, small, darkly-pigmented melanophores on several rows of scales (similar in color to scales on ocular-side head); central portion of posterior region of blind-side head with irregular patch of numerous, faint, small melanophores (visible under magnification). Two nearly parallel, zig-zagging rows of clusters of faintly-pigmented melanophores extending posteriorly from posterior margin of head nearly to caudal-fin base (Fig. 2 B); dorsal row located about 1/4th body width from dorsal-fin base, ventral row located medially just ventral to body mid-point. Single row of faint melanophores evident internally in dermis about at medial ends of proximal pterygiophores in both posterior 3/4ths of dorsal fin and for nearly entire length of anal fin. V