Pterygotrigla (Pterygotrigla) saumarez, Last, Peter R. & Richards, William J., 2012

Last, Peter R. & Richards, William J., 2012, Two new gurnards of the genus Pterygotrigla (Scorpaeniformes: Triglidae) from Australian seas, Zootaxa 3195, pp. 39-50 : 43-48

Pterygotrigla (Pterygotrigla) saumarez sp. nov.

Saumarez Gurnard

Figs 3–5 , Table 1

Holotype. CSIRO H 712–07, 186 mm SL, Australia, Queensland, south of Saumarez Reef, 22°10’S, 153°29’E, RV Soela SO 6/85/15, 303– 333 m, Nov. 1985.

Paratypes. 6 specimens. CSIRO H 646–04, 183 mm SL, Australia, Queensland, north of Saumarez Reef, 21°17’S, 153°31’E, RV Soela SO 6/85/ 18, 502 m, Nov. 1985; CSIRO H 709–03, 210 mm SL, Queensland, east of Saumarez Reef, 20°50’S, 153°58’E, RV Soela SO 6/85/17, 400– 403 m, Nov. 1985; CSIRO H 648–06, 269 mm SL, Australia, Queensland, off Townsville, 18°58’S, 149°23’E, RV Soela SO6/85/41, 452– 453 m, Nov. 1985; CSIRO H 712–08, 260 mm SL, taken with holotype; QM I 19294, 163 mm SL, Australia, Queensland, south of Swain Reefs, 23°59'S, 152°47'E, FV Craigmin, 293 m, Sep. 1980; QM I 19934, ~ 407 mm SL, Australia, Queensland, no data, FV Craigmin, Jun 2005.

Diagnosis. A species of the genus Pterygotrigla (reaching at least 407 mm SL) with the following combination of characters: snout short to moderately elongate, horizontal length about 2.3–2.7 in head length; orbit large, length 3.0– 3.9 in head; rostral spine very broad and becoming increasingly thickened almost to its tip, coarsely serrated at tip, length shorter than orbit length, about 5–10 in head; head well ossified (becoming increasingly hyperostotic in specimens exceeding 210 mm SL); interorbital depression strongly concave; parietal hyperostotic, forming a broadly elevated ridge above operculum; nuchal spine short, robust, broad based, not recurved, not extending past 2nd dorsal spine; cleithral spine very strong, not recurved, elongate, much longer than nuchal spine and extending beyond middle of first dorsal fin; opercular and preopercular spines weak; nasal and postocular spines absent; bucklers usually partly or fully embedded, predorsal buckler narrowly semicircular; dorsal-fin spines 2–4 substantially thickened, first spine shorter than next four spines; pectoral fin with 12 connected rays, very elongate, length 45–51% SL, extending beyond end of second dorsal-fin base in specimens less than 210 mm SL; vomerine tooth patch small; body scales small, cycloid; predorsal, prepectoral and interpelvic spaces, breast, and much of belly naked; pale without evidence of dark markings on body; pectoral-fin inner surface almost uniformly dark dorsally with anteriormost and posteriormost rays pale; posterior margin of caudal fin sometimes narrowly dark-edged; gill rakers 6–7, short; vertebrae 26.

Description. Dorsal rays VIII (VIII–IX), 12 (11); anal rays 12 (11–12); pectoral rays 12 + 3 (12 + 3); pelvic rays I, 5 (I, 5); principal caudal rays 11 (11–13); lateral-line pores to caudal base about 77 (64–78); gill rakers (excluding rudiments) 6 (6–7); vertebrae 26 (26).

Based on specimens 183–269 mm SL: Body moderately elongate, tapering strongly posteriorly; trunk deepest anteriorly, maximum depth 4.9 (4.1–4.4) in SL, 1.1 (1.2–1.3) times width across pectoral-fin base; caudal peduncle narrow, subrectangular in cross-section, length 2.8 (2.8–3.5) in caudal-fin length. Head well expanded, robust; surface granular, not pitted or covered with rugose striae; its length 2.9 (2.9–3.1) in SL; snout short to moderately elongate, deeply concave before orbit in lateral view, its length 2.4 (2.3–2.7) in head length. Rostral spine short, very broad, depressed in holotype, becoming bulbous in largest paratypes (well ossified), not recurved distally; apices bluntly rounded with multiple spinelets or serrations; length 1.9 (2.5–2.9) in snout length; length 1.6 (0.9–1.3) times its width; spines subparallel to each other, directed anteriorly, interspace between their bases less than their length. Nuchal spine broad based, short, strongly tapered, pungent; not recurved distally; extending to below 1st to 2nd dorsal-fin spines, 1.2 (1.0–1.2) times predorsal space; much shorter than cleithral spine, length 1.9 (2.0–2.4) in length of cleithral spine; longer than opercular spine in holotype but subequal in paratypes, length 1.3 (0.9–1.1) times length of opercular spine; parietal strongly ossified, forming a broadly elevated ridge above operculum; postorbital groove absent. Opercular spine short, slender, extending only slightly beyond margin of operculum, length 1.5 (1.2–1.3) in postorbital head length. Preopercular spine single, very slender, at posteriormost angle of preoperculum; similar in shape to opercular spine; very short, its length 1.5 (1.2–2.1) in length of opercular spine; spine absent at posteroventral angle of preoperculum; angles separated by a weakly concave margin. Nasal and postocular spines absent. Cleithral spine very broad based; tapering strongly from base, pungent; strongly depressed with its lateral edge forming an angular keel-like ridge; very elongate, reaching beyond middle of spinous dorsal fin, length 3.6 (2.7–4.6) times length of preopercular spine, 1.9 (1.8–2.1) in head length. Orbit lateral, large, length 3.1 (3.0–3.9) in head length, 1.3 (1.3–1.7) in snout length, 1.0 (1.0–1.2) in postorbital head length; margin of supraorbital rim elevated, prominent, not indented mid-dorsally. Interorbit deeply concave, width 1.2 (0.9–1.2) in orbit. Cheek relatively deep, height 0.8 (0.8–1.1) times orbital length; its bony portion 95% (92–96%) of its height. Mouth large with bands of fine villiform teeth on premaxilla and dentary; head of vomer with small oval to subcircular patch of fine villiform teeth; maxilla barely reaching anterior margin of orbit; length of upper jaw 2.4 (2.2– 2.4) in head length. Dorsal fins closely adjacent, spines alternating and partly depressible into a deep groove; predorsal buckler narrowly semicircular, obvious, its surface coarsely granular; about 8–9 subdorsal bucklers, all fully or partially embedded in epithelium; 3rd and 4th spines reaching anterior rays of second dorsal fin when depressed (not reaching fin in largest paratypes); longest dorsal-fin rays subequal in length to 5th spine; dorsal-fin spines mainly smooth, anterior margins of 1st and 2nd spines somewhat granular, but not serrate; spines 2–4 showing weak evidence of hyperostosis. Anal-fin origin more or less over second dorsal-fin origin but inserted slightly more posteriorly; longest ray subequal in length to longest dorsal-fin ray; its base slightly longer than base of second dorsal fin, length 1.3 (1.2–1.3) times length of base of second dorsal-fin. Pectoral fin very elongate, length 2.0 (1.9–2.2) in SL, reaching almost to end of anal-fin base; 1st free pectoral-fin ray moderately elongate, reaching to anus or just beyond, its length 1.9 (1.8–2.1) in length of pectoral fin. Pelvic fin elongate, length 3.8 (3.9–4.2) in SL, slightly longer than longest free pectoral-fin ray; reaching beyond origin of anal fin in holotype and smallest paratype, to anus in larger paratypes. Caudal fin lunate, tips of lobes narrowly pointed, length 3.6 (3.4–3.9) in SL. Body scales small, cycloid, longitudinally elongate, not fully embedded; scales absent from nape, base of cleithrum, breast, prepectoral and interpelvic areas, and anterior belly.

Ontogenetic changes. The largest paratype (QM I 19934, ~ 407 mm SL) is almost 140 mm longer and more than 3 times heavier than the largest described paratype. While not suitable for full morphometric analysis because it is twisted, this specimen differs from all other types in several characters that probably reflect ontogenetic changes (see Fig. 5 ). These differences include a more robust head with a much deeper suborbit (height about 1.4 times orbital length), more strongly defined striae on the head, shorter and more bulbous rostral spines with less well-defined apical serrations (interspace between their bases subequal to their length), nuchal spines relatively shorter and not reaching dorsal-fin origin, opercular and preopercular spines relatively more robust, dorsal fins more widely separated, and pectoral fins terminating well short of anal-fin insertion. The dentition and gill rakers were not examined.

Coloration. Fresh (from photograph of paratype CSIRO H 648–06), body and vertical fins mostly pale, whitish or pinkish; head darker pink (probably through damage); dorsum with large yellowish spots; eye yellow. In preservative, most of body and fins pale without evidence of dark markings. Pectoral-fin inner surface almost uniformly dark dorsally; some evidence of slightly darker, elongate proximal markings with 3–4 ventralmost rays and their membranes white; upper 1–2 rays paler than those adjacent but with dark connecting membranes; anterior half of outer surface of fin dusky, becoming darker posteriorly, surrounded dorsally and ventrally by paler rays and membranes. Caudal fin with very narrow, dark posterior margin.

Size. Attains at least 407 mm SL and 1.2 kg; smallest specimen examined 163 mm SL.

Distribution. Known from a small collection of specimens taken from the eastern Australian upper continental slope, and near the Swain and Saumarez Reefs (off central Queensland), at 293–502 m depth ( Fig. 6 ). Probably endemic to the Coral Sea, with its distribution centred in Australia’s northeastern deepwater biogeographic province ( Last et al., 2005).

Etymology. The epithet saumarez is used as a noun in apposition and refers to the general collection locality of most of the type specimens, the offshore plateau associated with the Saumarez Reef in the Coral Sea.

Comparisons. Pterygotrigla saumarez differs in many ways from the other new species described herein, P. gomoni . In P. saumarez the head is more strongly ossified and robust, some dorsal-fin spines are more thickened, the anteriorly directed rostral spines have a broadly serrated tip (rather than being narrowly pointed and diverging anterolaterally), the bucklers are better developed with the predorsal bucker narrowly semicircular (vs. all bucklers absent or fully embedded in P. gomoni ), the head lacks a postorbital groove, and the scales are less well embedded. The species also differ in many morphometric details (see Table 1 ). Pterygotrigla saumarez has a longer snout, pectoral fin, cleithral and opercular spines, a broader interorbit, and longer and broader rostral spines. The bony part of the cheek is more substantial as the upper suborbit is covered with a broad membranous area in P. gomoni . Pterygotrigla saumarez also has a much smaller nuchal spine, and a slightly smaller orbit and shorter postorbital head length. It is also unusual within the genus Pterygotrigla in having 26 vertebrae rather than 27 (see Richards & Jones, 2002). Of other described members of the subgenus Pterygotrigla , only P. guezei Fourmanoir in Fourmanoir & Guézé 1963 has a broad-based rostral spine that can be weakly serrate apically, but this species has a much longer eye to snout ratio, and a relatively shorter pectoral fin and longer nuchal spine than P. saumarez .

Comparative material examined. Pterygotrigla andertoni CSIRO H 3690–06, CSIRO H 3690–07; P. pauli CSIRO H 2463–04, CSIRO H 5002–01, CSIRO H 6057–04; P. polyommata CSIRO H 2597–04, CSIRO H 3676– 0 1, CSIRO H 3677–01, CSIRO H 3679–01, CSIRO H 3764–01; P. guezei SAIAB 61418.

P. gomoni P. saumarez

Holotype Paratypes Holotype Paratypes n=2 n=4

Material for this project would not have been obtained without the efforts of scientific and technical staff aboard former CSIRO research vessels Courageous and Soela, as well as crew on the FV Craigmin. In particular, we wish to thank S. Morrison ( WAM) and J. Johnson (QM) for making type material available at short notice. Curators of several ichthyological institutions in the region have generally made comparative triglid material available for our research: A. Stewart, C. Roberts and C. Struthers ( NMNZ), M. McGrouther (AMS), D. Bray and M. Gomon ( NMV). J. Pogonoski prepared radiographs of material held at CSIRO and compiled meristic data. We also thank J. Javech for his excellent drawings and L. Massey for file formatting assistance. Alastair Graham ( CSIRO) helped facilitate loans of material for much of this research and W. White prepared the map figure. We thank Martin Gomon for his comments on the manuscript.

Figures

FIGURE 3. Illustrations of the holotype of Pterygotrigla saumarez sp. nov. (CSIRO H 712 – 07, 186 mm TL): A, lateral view; B, dorsal view of head. A patch of scales shown below the first dorsal fin is representative of other scaled areas.

FIGURE 4. Pterygotrigla saumarez sp. nov.: A, lateral view of a paratype (CSIRO H 648 – 06, 269 mm TL, when fresh); B, view of partially expanded inner surface of right pectoral fin (reversed) of holotype (CSIRO H 712 – 07, 186 mm TL, preserved) showing markings.

FIGURE 5. Head morphology of largest Pterygotrigla saumarez sp. nov. paratype (QM I 19934, ~ 407 mm SL, preserved): A, lateral view; B, dorsal view.

FIGURE 6. Map of the Australian region showing the distributions of Pterygotrigla gomoni (blue dot) and P. saumarez (red dots).

Tables

TABLE 1. Morphometric data for the holotypes of Pterygotrigla gomoni sp. nov. (WAM P 26270 - 004) and P. s a u m a re z sp. nov. (CSIRO H 712 - 07), and ranges for the paratypes of these species. Data are expressed as percentages of SL (given in mm); an asterisk is used to flag data where information is missing for a specimen due to damage.

Standard length (mm) 156 Body depth 20.4	156–174 21.2–22.3	186 20.6	183–269 22.9–24.5
Head length 33.5 Postorbital head length 11.4 Snout length 11.0 Rostral spine length 4.2	32.4–33.6 11.2–11.9 11.1–11.4 4.7–4.7	33.9 11.3 14.2 7.6	32.0–34.8 10.7–10.8 13.9–15.1 4.9–5.7
Rostral spine width 2.2 Orbital length 11.6	2.6–2.8 10.5–10.7	4.8 11.0	4.4–5.2 8.9–10.9
Interorbital width 7.9 Cheek height (maximum) 8.1 Cheek height (bony portion) 6.2 Gill raker length 1.2	6.6–7.9 8.1–8.6 6.5–6.6 1.5–1.6	9.2 8.6 8.2 1.8	8.7–9.6 9.2–10.2 8.6–9.8 1.0–1.8
Premaxilla length 15.1 Opercular spine length 7.0	14.1–14.1 7.2–7.4	14.3 7.6	13.3–15.6 8.0–8.7
Preopercular spine length 4.5 Nuchal spine length 11.1 Cleithral spine length 8.8 Predorsal space 9.3 Dorsal-fin spine 1 length damaged Dorsal-fin spine 2 length 12.1	4.2–4.3 10.0–10.7 8.8–9.5 8.5–8.8 8.3–9.4 15.4–15.8	5.1 9.5 18.1 8.1 7.5 15.1	3.9–6.9 7.4–9.3 16.8–18.8 7.1–9.1 7.1–10.8 13.9–16.8
Dorsal-fin spine 3 length 15.5 Dorsal-fin ray length (longest) 13.2 Second dorsal-fin base length 25.2 Anal-fin ray length (longest) 10.9 Anal-fin base length 29.6 Caudal peduncle length 8.7	18.6–18.6* 11.9–13.7 22.8–24.3 10.8–11.6 27.6–28.8 9.4–9.9	17.9 12.9 22.7 12.6 28.8 9.8	16.8–18.4* 12.2–13.4 23.2–23.9 11.0–12.7 28.0–29.6 8.1–9.9
Caudal-fin length 28.0 Pectoral-fin length 31.1 Pectoral free ray 1 length 26.5 Pectoral free ray 2 length 22.8 Pectoral free ray 3 length 17.9 Width across pectoral-fin base 17.6	26–26.7 28.8–34.1 25.6–26.6 21.8–22.8 17.8–18.8 20.0–20.2	27.6 51.2 26.6 22.1 17.9 18.2	25.9–29.4 45.0–51.4 24.4–25.1 20.4–22.1 16.0–18.1 19.2–20.3
Pelvic-fin length 27.0 Width across pelvic-fin base (minimum) 6.1	25.4–26.4 5.9–6.6	26.3 4.4	23.8–25.9 5.8–7.9
Acknowledgments