Parapercis imamurai, Johnson & Wilmer, 2018

Johnson, Jeffrey W. & Wilmer, Jessica Worthington, 2018, Three new species of Parapercis (Perciformes: Pinguipedidae) and first records of P. muronis (Tanaka, 1918) and P. rubromaculata Ho, Chang & Shao, 2012 from Australia, Zootaxa 4388 (2), pp. 151-181 : 163-168

Parapercis imamurai sp. nov.

New English name: Imamura’s Sandperch Figures 1 , 3A–C , 8 ; Tables 1–3

Parapercis sp. 2: Last et al., 2014: appendix 1 (listed in table).

Holotype. CSIRO H. 630-16, 156 mm, south of Saumarez Reef , Qld, Australia, 22°35.3’S 153°46.7’E to 22°36.3’S 153°50’E, 345–350 m, lobster trawl, CSIRO on FRV Soela, 17 Nov 1985 .

Paratypes. (n = 5) AMS I.33436-005, 95.7 mm, off Coffs Harbour , NSW, Australia, 30°18’S 153°27’E, 256 m, trawl, T. Nyssen, 7 Sept 1992 ; CSIRO H.630-06, 2: 76.9–113 mm, same data as holotype ; CSIRO H. 720-26, 146 mm, south of Saumarez Reef , Qld, Australia, 23°12.6’S 153°37.8’E to 23°12.1’S 153°33.4’E, 399–405 m, lobster trawl , CSIRO on FRV Soela, 18 Nov 1985; CSIRO H. 720-27, 208 mm, same data as previous .

Diagnosis. A species of Parapercis with dorsal-fin rays V, 21; anal-fin rays I, 17; pectoral-fin rays 19–20 (usually 19); lateral-line scales 55–58 (modally 57); gill rakers 5–7 + 11–12 = 16–18 (modally 17); predorsal scales 10–12, ctenoid, extending forward to or just anterior to vertical from upper corner of preopercle; scales on cheek ctenoid, except for some small cycloid scales anteriorly near lower margin of suborbital region, extending forward to tip of maxilla in adults, slightly further forward in juveniles; fifth dorsal-fin spine longest; 10 canine teeth in outer row at front of lower jaw; vomer with 3 rows of robust conical teeth in adults (2 rows in some juveniles); palatines edentate; hind margin of preopercle usually entire, angle with 2–4 low blunt serrations in adults, with more robust pointed spines in some juveniles; angle of subopercle with single broad, flattened spine; 10 abdominal and 19 caudal vertebrae; pelvic fins reaching vent in adults, slightly beyond vent in juveniles; and colouration pale brownish pink, with broad diffuse dusky bar from lower margin of eye across suborbital region, three broad diffuse dusky bands across the body and caudal-fin base, first on soft dorsal fin below base of dorsal-fin rays 6–11, second below base of dorsal-fin rays 15–19, third from posterior portion of caudal peduncle extending onto caudal-fin base; bands distinct in juveniles, becoming more faint with growth; juveniles with large black blotch in lower half of soft dorsal fin between rays 6–9 and 16–18 and anal fin black, the pigmentation on fins reducing with growth, faint or absent in large specimens.

Description. Morphometrics and meristics are presented in Table 3. Dorsal-fin rays V, 21; anal-fin rays I, 17; all dorsal- and anal-fin rays branched, last to base; pectoral-fin rays 19 (19–20, usually 19, asymmetrically 19 on one side and 20 on opposite in one paratype), upper ray unbranched, others including lowermost branched; pelvicfin rays I, 5; branched caudal-fin rays 15; lateral-line scales 57 (55–58), plus 4 (3–4) smaller pored scales on caudal-fin base; scales above lateral line to origin of dorsal fin 5, to base of anterior soft rays of dorsal fin 3 ½; scales below lateral line to origin of anal fin 13 (13–14); circumpeduncular scales 22; predorsal scales 11 (10–12), extending to (to or just beyond) vertical from upper corner of preoperculum; horizontal row of scales from preorbital across cheek to edge of preopercle about 18, vertical rows below middle of eye 11; gill rakers on first arch 7 + 11 = 18 (5–7 + 11–12 = 16–18); branchiostegal rays 6; vertebrae 10 + 19 = 29.

Body depth 4.9 (4.9–5.5) in SL; body subcylindrical, greatest width 0.9 (0.9–1.0) in body depth; head length 3.4 (3.4–3.6) in SL; snout bluntly pointed, its length 3.8 (3.7–3.9) in HL; orbital diameter 2.7 (2.7–2.9) in HL; eyes directed more laterally than dorsally, bony interorbital space narrow, 17.5 (11.1–21.7) in HL; caudal-peduncle depth 3.1 (2.9–3.3) in HL; caudal-peduncle length 3.7 (3.3–3.7) in HL.

Mouth oblique, jaws terminal (terminal, or upper lip slightly protruding beyond tip of lower jaw); curved canine teeth at front of lower jaw slightly projecting, but not visible when mouth closed; upper jaw extending to vertical from anterior margin of eye (anterior margin of eye to anterior third of eye), no fleshy flap extending posteriorly from tip of maxilla, upper-jaw length 2.7 (2.6–2.8) in HL; upper jaw with 22 (20–22) outer curved canines on each side, middle teeth largest, those following gradually reducing in size posteriorly, broad inner band of small villiform teeth anteriorly, narrowing gradually to form only two rows at rear of jaw; front of lower jaw on each side with 5 enlarged curved canines in distinctly separate outer row (one paratype with 5+4 and one with 6+5, but usually 5 teeth on each side when undamaged), pair at symphysis slightly larger than others, outer row then consisting of additional 19–20 (18–20) slightly smaller teeth, of which 9th (9th–10th) is slightly enlarged; broad inner band of villiform teeth extending posteriorly from symphysis to side of jaw just posterior to largest tooth in outer row, remaining teeth subequal, of moderate length, in single row. Vomer with 3 (2–3, 2 rows only in two smallest paratypes) irregular crescentic rows of teeth, 8 (5–7) robust conical teeth in anterior row, medial teeth largest, second row shorter, comprised of 7 (4–5) slightly smaller teeth, third row with 5 (0–5) small, more scattered teeth; palatines edentate. Tongue spatulate with broadly rounded tip, dorsal surface covered with numerous small papillae.

Gill membranes united with broad free fold, not attached to isthmus. Gill rakers short, longest about 3 (3–4) in length of longest gill filament on first gill arch. Anterior nostril small, situated anterior to mid-eye, just short of half distance from anterior margin of eye to snout tip, with membranous tube bearing distinct flap posteriorly, flap taller than remaining height of tube. Posterior nostril slightly more than half distance from anterior margin of eye to anterior nostril, dorsoposterior to, and about 1.5 times width of anterior nostril, its opening round (round to ovalshaped), with slightly raised rim; internarial distance about 1.5 (1.5–2.0) times width of posterior nostril.

Opercle with distinctly exposed, flattened, blade-like spine; angle of subopercle with single broad flattened spine (distinctly pointed in one paratype); hind and lower margins of preopercle entire (two paratypes with 2 small serrations on hind margin), angle with 3 (2–4, usually 3) low blunt (blunt to sharply pointed) serrations.

Lateral line continuous, ascending smoothly from opercle to below second (first or second) soft dorsal-fin ray, then approximately following contour of back; scales ctenoid, except for few cycloid scales on midline of belly (largest paratype with all belly scales ctenoid), and several lowermost scales on subopercle (larger paratype with all scales on suborbital ctenoid); scales on middle of sides with up to about 52 cteni; scales on cheek extending forward to vertical from anterior margin of orbit (anterior margin of orbit in larger paratypes to anterior margin of pupil in juveniles); no scales on dorsal, anal or pelvic fins; small ctenoid scales followed by few elongate cycloid scales on basal quarter of pectoral-fin rays; elongate ctenoid scales densely arranged on proximal two-thirds of caudal fin.

Origin of dorsal fin slightly posterior (distinctly posterior in juveniles) to vertical from axil of pectoral fin, predorsal length 3.2 (3.1–3.3) in SL; dorsal-fin spines progressively longer, first 6.2 (5.1–6.1) in HL; fifth spine longest, 3.5 (2.7–3.5) in HL; membrane from fifth spine to first soft ray attached near tip of fifth spine and barely incised; 18th (17th to 20th) soft dorsal-fin ray longest, 1.9 (1.6–1.8) in HL. Origin of anal fin below base of fifth soft dorsal-fin ray, preanal length 1.9 (1.9–2.0) in SL; anal-fin spine slender, closely attached to first soft ray, 6.1 (4.3– 5.1) in HL; 15th (15th or 16th) soft anal-fin ray longest, length 2.2 (2.0–2.3) in HL. Caudal fin slightly rounded (truncate to slightly rounded), length 5.1 (4.4–5.1) in SL. Pectoral fins rounded, 11th (10th or 11th) ray longest, 3.6 (3.5–3.6) in SL, longer than pelvic fins. Origin of pelvic fins in advance of upper base of pectoral fins, on vertical just posterior to upper corner of opercular opening, prepelvic length 3.2 (3.2–4.0) in SL; pelvic-fin spine closely attached to first soft ray, its termination not protruding, reaching about three fourths distance to tip of first ray; fourth soft pelvic-fin ray longest, reaching vent (to vent in largest paratype, slightly anterior to base of anal-fin spine in smallest paratype), length 4.8 (4.0–4.8) in SL.

Colour when fresh. Based on photograph (fig. 3A, upper specimen), holotype pale brownish pink; upper half of body and head infused with slightly darker brown than lower half; broad diffuse dusky bar from lower margin of eye, across suborbital to about posterior fifth of upper jaw, extending posteriorly just beyond tip of maxilla; body with two large dusky saddles and darker blotch on posterior portion of caudal peduncle, latter extending onto anterior fourth of caudal fin. First saddle on body below soft dorsal-fin rays 6–11, not quite reaching anal-fin base, second below base of soft dorsal-fin rays 15–19, reaching lateral line. Dorsal, anal and caudal fins pale yellow, anal fin with posterior tip black. Pelvic fins whitish, at least along outer edge.

Fresh colouration of juvenile, based on photograph of paratype CSIRO H.630-06, 76.9 mm SL (fig, 3A, lower specimen), similar to holotype, except dark bar on suborbital region, saddles on body and blotch on caudal-fin base darker and more extensive; suborbital bar jet black, covering entire suborbital region and extending onto lower portion of preopercle and interopercle; saddles on body and blotch on caudal-fin base traversing entire side of body, the latter jet black; two large jet black blotches present on lower half of soft dorsal-fin, blotches between soft dorsal-fin rays 6–9 and 16–18, one above each dusky saddle on body.

Colour in alcohol. Head and body of holotype (fig. 3B) pale creamy brown; faint broad dusky bar from lower margin of eye, across suborbital to about posterior fifth of upper jaw, extending posteriorly to just beyond tip of maxilla; body with two dark brown saddles and dark brown blotch on centre of posterior portion of caudal peduncle, latter extending onto anterior fourth of caudal fin. First saddle on body below soft dorsal-fin rays 6–11, reaching about four-fifths distance to anal-fin base, second below base of soft dorsal-fin rays 15–19, barely reaching lateral line. Dorsal, anal and caudal fins semitranslucent; posterior tip of anal fin faintly dusky. Outer pelvic-fin rays pale, inner half faintly dusky.

Juvenile paratypes, CSIRO H.630-06, 76.9–112.8 mm and AMS I.33436-005, 95.7 mm, with broader dusky bar on suborbital region, covering entire suborbital region and extending onto lower portion of preopercle and interopercle. Dusky saddles on body and dusky blotch from caudal peduncle to anterior fourth of caudal-fin base broader, traversing entire side of body and fin. Two black blotches present on lower half of soft dorsal-fin, one above each dusky saddle on body, blotches situated between soft dorsal-fin rays 6–9 and 16–18 in smallest paratype, between soft dorsal-fin rays 7–9 and 15–18 in 95.7 mm paratype. Smallest paratype with anal fin entirely black, except for pale tips on rays 1–6; 95.7 mm paratype with basal four-fifths of fin black and distal one-fifth pale on rays 1–13, remaining posterior rays entirely black; 112.8 mm paratype with first seven rays pale, following fin tips then black, with dark pigmentation progressively descending obliquely to the base on rays 8–16, last ray entirely black.

Molecular results. No genetic samples were available for P. imamurai , so no genetic analysis was possible.

Etymology. Named for Dr. Hisashi Imamura, Japan, in honour of his valuable contributions to the taxonomy of pinguipedid fishes.

Distribution and abundance. Collected from soft to rubbly bottom by demersal trawl from south of Saumarez Reef, Qld (22°35.3’S 153°46.7’E) to off Coffs Harbour, NSW (30°18’S 153°27’E), Australia, at depths of 256–405 m (fig. 8).

The species appears relatively rare, with only six specimens collected by trawl from three sites, however collecting efforts in the known depth range of the species have been sparse in large areas off the north-east coast of Australia.

Discussion. Parapercis imamurai (fig. 3A–C) is readily distinguished by its distinctive colouration, including a large dark bar on the suborbital, two dark saddles across the posterior half of the body and a dark blotch spanning the caudal-fin base. Among congeners, only Parapercis allporti ( Günther, 1876) and Parapercis gilliesii ( Hutton, 1879) share the same combination of fin-ray and gill raker counts, similar lateral-line scale counts and have the fifth dorsal spine longest. However, both species have more numerous and narrower dark transverse bars or other markings spread throughout the length of the body and lack a dark bar below the eye. In addition to colouration, both may be distinguished from P. imamurai in having fewer teeth in the outer row of the lower jaw (8, versus 10 in P. imamurai ). Furthermore, P. allporti has a much longer first dorsal-fin spine (subequal to fifth spine, versus about half length of fifth spine in P. imamurai ) and P. gilliesii has fewer vomerine teeth in only two rows (teeth 3–5 + 1– 2, versus 3 rows in adults and 2 in juveniles, 5–8 + 3–7 + 0–5 in P. imamurai ) and usually more lateral-line scales, predorsal scales and scales above the lateral line to the base of the first dorsal-fin spine (58–64, 12–14 and 7 respectively, versus 55–58, 10–12 and 5 in P. imamurai ).

Figures

FIGURE 1. Maximum clade credibility Bayesian tree of species of Parapercis and outgroup taxa. Clade support is indicated by posterior probabilities ± 0.95 above the branch and bootstrap values ± 70 representing a topologically identical best maximum likelihood tree are below the branch.New Australian records of P. muronis and P.rubromaculata are indicated with an asterix *. Scale represents average number of substitutions per site.

FIGURE 3. Type specimens of Parapercis imamurai sp. nov. A. Holotype, CSIRO H.630-16, 156 mm SL (upper) and paratype, CSIRO H.630-06 mm, 76.9 mm SL (lower), south of Saumarez Reef, Qld, Australia, fresh (Photo: CSIRO); B. Holotype, preserved; C. Paratype, CSIRO H.630-06, 76.9 mm SL, same data as holotype, preserved.

FIGURE 8. Collection localities for three new species and two new records of Parapercis, based on material examined (P. algrahami = red spheres, P. imamurai = black stars, P. pogonoskii = black spheres, P. rubromaculata = red stars, P. muronis = red squares (Map courtesy of CartoGIS Services, College of Asia and the Pacific, Australian National University).