Urolophus kapalensis, Gordon K. Yearsley & Peter R. Last, 2006

Gordon K. Yearsley & Peter R. Last, 2006, Urolophus kapalensis sp. nov., a new stingaree (Myliobatiformes: Urolophidae) off eastern Australia., Zootaxa 1176, pp. 41-52 : 42-51

Urolophus kapalensis sp. nov.

Kapala Stingaree

(Figs. 1-5)

Urolophus sp. A : Last & Stevens 1994, 428, fig.

Trygonoptera testacea (non Müller & Henle): Kuiter 1996, p. 20, fig.

Urolophus sp.: Edgar 1997, p. 400, fig.

Holotype. CSIRO H 999-02, 345 mm TL, mature male, Jervis Bay, N.S.W. (35°02’S, 150°45’E), Tasman Sea, southwestern Pacific Ocean, 18-22 m depth, coll. by FRV Kapala, 14 Nov. 1984.

Paratypes. 9 specimens. All from the Tasman Sea, southwestern Pacific Ocean. CSIRO H 74-03, 361 mm TL, female , CSIRO H 74-05, 403 mm TL, female , CSIRO H 74- 09, 440 mm TL, female, Jervis Bay, N.S.W. (35°05’S, 150°44’E), 20-30 m depth, coll. by FRV Kapala, 4 Apr. 1984 ; CSIRO H 999-09, 429 mm TL, female , CSIRO H 999-11, 343 mm TL, mature male , CSIRO H 999-13, 365 mm TL, mature male , CSIRO H 1002-05, 276 mm TL, female, same data as holotype ; NMV A 25097-001, 220 mm TL, male, Disaster Bay, N.S.W. (37°16’S, 149°58’E), 22-31 m depth, coll. by FRV Southern Surveyor, 3 Aug. 1993 ; NMV A 25098-001, 250 mm TL, female, east of Lake Macquarie, N.S.W. (33°05’S, 151°42’E), 27-33 m depth, coll. by FRV Kapala, 30 Mar. 1993 .

Other material. All from the southwestern Pacific Ocean. CSIRO C 2850, 144 mm TL, immature male, Botany Bay, N.S.W. (approximately 33°59’S, 151°11’E), depth unknown, coll. by FV Jaybee, 27 May 1953 ; CSIRO H 74-04, 370 mm TL, female, Jervis Bay, N.S.W. (35°05’S, 150°44’E), 20-30 m depth, coll. by FRV Kapala, 4 Apr. 1984 ; CSIRO H 874-01, 327 mm TL, mature male, east of Yamba, N.S.W. (29°28’S, 153°30’E), 50-54 m depth, coll. by FRV Kapala, 26 May 1986 ; CSIRO H 875-07, 387 mm TL, mature male, east of Crowdy Head, N.S.W. (31°50’S, 152°51’E), 76 m depth, coll. by FRV Kapala, 23 Jul. 1986 ; CSIRO H 908-01, 360 mm TL, female , CSIRO H 908-04, 399 mm TL, mature male, east of Sydney, N.S.W. (33°58’S, 151°17’E), 47-64 m depth, coll. by FRV Kapala, 25 Mar. 1987 ; CSIRO H 916-05, 357 mm TL, mature male, east of Port Stephens, N.S.W. (32°41’S, 152°16’E), 45-63 m depth, coll. by FRV Kapala, 11 Apr. 1985 ; CSIRO H 930-04, 326 mm TL, mature male, north of North Solitary Island, N.S.W. (29°49’S, 153°24’E), 36-54 m depth, coll. by FRV Kapala, 24 Mar. 1985 ; CSIRO H 1002-04, 309 mm TL, mature male, same data as holotype ; CSIRO H 3540-02, 433 mm TL, mature male , CSIRO H 3540-03, 521 mm TL, female, east of Bermagui, N.S.W. (36°21’S, 150°07’E), 27-28 m depth, coll. by FRV Southern Surveyor, 14 Aug. 1993 ; CSIRO H 6153-01, 341 mm TL, mature male , CSIRO H 6153-02, 212 mm TL, immature male , CSIRO H 6153-03, 213 mm TL, female, off Cape Moreton, Qld (about 27°02’S, 153°29’E), 79 m depth, coll. by FV Billy Joe, 7 Feb. 2004 ; NMV A 28034-001 346 mm TL, mature male , NMV A 28034-002, 250 mm TL, female , NMV A 28034-003, 167 mm TL, immature male, Sydney Harbour, N.S.W. (33°49’S, 152°17’E), 9-15 m depth, coll. by FRV Kapala, 9 Sep. 1981 .

Diagnosis. A medium-sized Urolophus , a genus that lacks broad lobes on posterolateral border of nostrils, with the following combination of characters: subcircular to weakly rhomboidal disc, width less than 62% TL; bell-shaped internasal flap; tail with well-developed lateral cutaneous folds; stinging spine long, 12-15% TL; dorsal fin low but prominent, free-rear tip over spine origin; total vertebrae 156-170; pre-spine vertebrae 86-95; dorsal surface of disc greenish, paler laterally; usually with dark suborbital blotch and V- shaped interorbital bar.

Description. Disc subcircular (subcircular to weakly rhomboidal in paratypes), not especially broad, wider than long; width 1.1 times length, 5.0 (4.6-5.0) times distance between first gill slits; broadest about 1.5 (about 1-2) eye diameters behind level of spiracles; anterior profile obtuse; anterior disc margins almost straight (very weakly concave to weakly convex); pectoral apices broadly rounded; posterior disc margins convex (Fig. 1). Snout fleshy, tip angular, barely extended; preoral snout length 3.1 (2.7-3.2) times internarial distance, 1.1 (0.9-1.0) times distance between first gill slits; direct preorbital snout length 3.2 (2.6-3.8) times interorbital distance; snout to maximum disc width 2.5 (2.7-2.8) times in DW; interorbital space broad, almost flat (sometimes slightly concave); orbital region barely distinguishable from head (sometimes elevated well above interorbit, elevation also evident from underwater photographs of non-types), orbit diameter 0.8 (0.8-1.0) in spiracle length; eye of moderate size (small to moderate), lateral, 24% (22-29%) preocular snout length, 12% (10-13%) ventral head length, diameter 1.1 (1.1-1.4) in spiracle length; lower half of eye separated from spiracle by thick, fleshy curtain consisting of several irregular longitudinal skin folds (when eyes raised, curtain wholly below eye); curtain originating just in advance of mid-eye, inserted near posterior margin of orbit; inter-eye distance 2.5 (2.5-3.1) times eye diameter. Spiracles narrowly tear-shaped and recurved medially, greatly enlarged, opening dorsally (dorsolaterally in paratypes with raised eyes), slightly smaller than orbit, posterior margin bluntly rounded (bluntly rounded to slightly angular), interspiracular distance 1.8 (1.8-2.2) times interorbit distance. Mouth small, slightly convex (slightly convex, occasionally almost straight), width 2.5 (2.1-2.7) in snout tip to lower jaw; in dissected paratypes CSIRO H 999-09 and CSIRO H 999-11, 7 oral papillae on floor, not arranged in a single series, scattered on a ’W-shaped’ line; single mesial papilla bifid; 3 lateral pairs located distally to mesial papilla, more-or-less equidistant, first closer to mesial papilla than to second papilla; those near angle of jaw about half height of other papillae; external patch of papillae below symphysis of lower jaw welldeveloped, appearing as ridges or short longitudinal folds. Internasal flap small, distinctly bell-shaped, distinctly broader distally than anteriorly (Fig. 2A), width 1.9 (1.7-2.0) times length, 1.6 (1.3-1.7) times internasal distance; anterolateral margin convex, elevated slightly, forming a low cutaneous ridge; posterior lateral lobe apex extended, narrow, pronounced, depressible into a deep oronasal groove; distal fringe well developed, its margin irregular, separated from anterior portion of flap by weak groove, connected directly to posterior lateral lobe. Nostril slightly oblique, slightly shorter than internasal flap, with approximately 38 nasal lamellae in holotype; posterolateral margin entire, concave, forming a weak cutaneous knob just in advance of its posterior margin; no broad, flattened fleshy lobe. Jaws strongly asymmetric; upper jaw subrectangular, labial margin almost straight, directed posterolaterally near angle, without exposed tooth rows (Fig. 3A); lower jaw subtriangular, labial margin near symphysis straight, consisting of 9 (6-8 in dissected CSIRO H 999-09 and CSIRO H 999-11) outer exposed tooth rows (Fig. 3B). Teeth quincuncial; in female (CSIRO H 999-09), rhomboidal labially in lower jaw; labial margin of cusp less angular than lingual margin; lingual teeth larger than labial teeth, not abutting those adjacent; cusps of teeth towards middle of jaw more pronounced than those distally; teeth in upper jaw similar in size and shape to labial teeth of lower jaw; in male (CSIRO H 999-11), labial upper-jaw teeth weakly rhomboidal, labial margins blunt or weakly concave, much less angular than lingual margin, 5 inner series of lower jaw with prominent posteriorly directed cusps, most pronounced towards lingual margin of tooth band; in upper jaw, teeth near labial margin similar to those of lower jaw, series 4 and further lingually with prominent cusps.

Gill openings moderately S-shaped, non-fringed, margin membraneous; length of first gill slit 1.6 (1.4-2.1) times length of fifth gill slit, 3.2 (2.5-2.9) times in mouth width; distance between first gill slits 2.8 (2.7-3.2) times internasal distance, 0.4 (0.4-0.5) times ventral head length; distance between fifth gill slits 1.9 (1.8-2.3) times internasal distance, 0.3 times ventral head length.

Body entirely smooth, sensory pores indistinct dorsally; subcutaneous canal system evident ventrally.

Tail rather elongate, postcloacal length 87% (82-90%) disc length; very depressed anteriorly, tapering strongly near pelvic-fin insertions, less strongly tapered near caudal fin; subcircular above anterior part of hypocaudal lobe of caudal fin, compressed below epicaudal lobe; flattened beneath stinging spine; lateral cutaneous tail folds well developed, terminating abruptly near posterior base of stinging spine (Fig. 4). Dorsal fin low, base relatively long, height slightly less than half eye diameter, apex broadly rounded, free rear tip short, over spine origin. Pelvic fins semicircular, moderate (small to moderate), length 1.5 (1.4-1.7) in greatest width across both fins, outer margin very broadly rounded, anterior and posterior margins strongly convex, free rear tip weakly angular. Caudal fin usually narrowly lanceolate (broader in some paratypes), epicaudal-lobe length 3.2 (2.8- 3.5) times fin height; hypocaudal lobe 5.3 (3.7-6.0) times fin height. Clasper robust, short, subconical, slightly depressed, weakly tapering, bluntly pointed distally.

Stinging spine very elongate, length 0.9 (0.9-1.1) times in epicaudal lobe length, serrated for about posterior half, point pungent; holotype with 16 recurved serrations on lefthand side of spine.

Tooth rows (in paratypes CSIRO H 999-09 and CSIRO H 999-11) 25 in upper jaw, 31-32 in lower jaw. Pectoral-fin radials 93-94 (93-105) in total, 47-48 (43-50) propterygial, 10-11 (9-13) mesopterygial, 35-36 (36-47) metapterygial. Total pelvic-fin radials 20 (22-23 in males; 22-26 in females). Postsynarcual vertebral centra 170 (156-169) in total, 86 (86-95) in pre-spine total, 30 (30-33) monospondylous, 56 (56-63) pre-spine diplospondylous, 84 (68-83) post-spine tail vertebrae.

Color when fresh (based on all material available). Dorsal surface of central disc and tail greenish (live coloration shown in Fig. 5); outer margin of disc posterior to eye paler yellowish or brownish; pelvic fins similar to posterior disc margin; whitish where skin removed. Variable dark pattern usually present on upper surface; dark subtriangular blotch adjacent eye, its length slightly exceeding combined orbit and spiracle length (blotch usually pronounced but sometimes faint); thin, dark V-shaped bar extending across interorbit, its apex directed posteriorly, variable in intensity and width; sometimes with dark mid-pectoral blotch and stripe from interorbit to tail base, absent in holotype; dark, irregular blotch at base of pelvic fin, indistinct in holotype, often prominent and extending anteriorly onto pectoral-fin base; clasper base pale, dark mid-dorsally. Ventral surface whitish with darker, broad marginal band on pectoral-fin; marginal band yellowish or dusky, extending from anterior disc forward of mouth to pectoral-fin insertion, maximum width (near pectoral-fin apex) subequal to prenasal length; similar marginal band on pelvic fin. Tail mainly whitish dorsally, with darkish, variable, mid-dorsal stripe; mainly whitish on and below lateral fold; ventral tail darker posterior to fold, sometimes with scattered darker blotches, usually dusky or brownish beside hypocaudal lobe. Dorsal fin greenish brown; caudal fin dark greyish brown, darker in juveniles. Clasper pale. Stinging spine yellowish or whitish.

Color of preserved specimens. Upper surface uniformly brownish, without evidence of green coloration; dark patches on suborbit persisting and, to a lesser extent on interorbit and pelvic-fin bases (dark patches more or less evident in paratypes). Ventral surface generally pale, yellowish; marginal band distinct, often faint; oronasal region, teeth and buccal cavity uniformly pale; dark markings on tail persistent.

Size. Largest specimen examined was a female of 521 mm TL and 312 mm DW (CSIRO H 3540-03). The largest male examined was 433 mm TL (CSIRO H 3540-02). The smallest mature male examined was 309 mm TL (CSIRO H 1002-04). The smallest specimen examined, lacking an umbilical scar and presumably postnatal, was a 144 mm TL juvenile male (CSIRO C 2850).

Distribution and habitat. Known only from the continental shelf off eastern Australia, mostly in the northern Tasman Sea. Based on material listed above, and additional material held at CSIRO, the species ranges from Cape Moreton, Qld (about 27°02’S, 153°29’E), south to Disaster Bay, N.S.W. (about 37°15’S, 149°58’E), in depths of 9-79 m.

In N.S.W. waters, it is common in the southern part of its range in depths less than 50 m, and is relatively rarely caught north of Clarence River (about 29°29’S 152°40’E) (K. Graham pers. comm.). However, in a series of south-east Qld surveys, in which the new species was the subject of a biological study, it was locally common, and the majority of specimens (86%) were found at depths greater than 62 m (P. Kyne, pers. comm.).

Etymology. This new species was discovered among specimens collected by the FRV Kapala (formerly of the N.S.W. Fisheries Research Institute, Australia). The species is named kapalensis to honour the extremely valuable fish collections made by the vessel over almost three decades.

Remarks. In addition to dorsal coloration, a combination of the presence of lateral cutaneous tail folds, a dorsal fin, and a bell-shaped internasal flap distinguish Urolophus kapalensis from all other known Urolophus species. The presence or absence of lateral cutaneous tail folds in U. javanicus (Martens) and U. kaianus Guenther is unknown, but these non-Australian species differ from U. kapalensis in having a skirt-shaped internasal flap; U. kaianus also lacks a dorsal fin. Of the species where the condition of the lateral cutaneous tail folds is known, U. aurantiacus Mueller & Henle , U. circularis McKay , U. cruciatus ( Lacepede) , U. deforgesi Seret & Last , U. gigas Scott , U. orarius Last & Gomon and U. sufflavus Whitley all lack tail folds, whereas U. kapalensis has well-developed folds. The other remaining species have variably developed tail folds (sometimes intraspecifically present or absent) but, of these, U. armatus Mueller & Henle , U. expansus McCulloch , U. lobatus McKay , U. mitosis Last & Gomon , U. neocaledoniensis Seret & Last , U. paucimaculatus and U. viridis McCulloch lack a dorsal fin, which is present in U. kapalensis . In U. westraliensis Last & Gomon , the dorsal fin is variably present but, along with U. bucculentus Macleay , U. flavomosaicus Last & Gomon , U. papilio Seret & Last and U. piperatus , the internasal flap is skirt shaped (see example in Fig. 2B), compared with bell shaped (Fig. 2A) in U. kapalensis . In fact, U. kapalensis is one of only two known Urolophus species with a bell-shaped internasal flap. The other species, U. paucimaculatus , occurs sympatrically with U. kapalensis off central and southern N.S.W., but its distribution extends further south, around Tasmania and west across the Great Australian Bight to about Perth, Western Australia. Urolophus kapalensis is distinguished from U. paucimaculatus by the presence of a dorsal fin (lacking in U. paucimaculatus ), a narrower disc (disc width 4.6-5.0 vs about 5.1 times distance between first gill slits; see Table 1), a longer stinging spine (11.8-14.9 vs 9.3-11.5% TL), a shorter spiracle (0.8-1.0 vs 1.1-1.2 times orbit length), more pre-spine vertebrae (86-95 vs 79-88), and by a dark, V-shaped band across the interorbit, usually accompanied by dark blotches adjacent to each eye (absent) and dark blotches at the base of the pelvic fins (absent).

The dorsal colour pattern of this species is considerably variable within a discrete range of tones. In some material, the dark interorbital bar was absent, the mid-interorbital region sometimes being paler than adjacent surfaces. There was also evidence of a weak, dusky marking between the spiracles. The blotch beside the eye was often weak or absent, and no other obvious blotches or bands were evident. Two other specimens also displayed unusual coloration. CSIRO H 74-04 differed from 8 typical forms of the species collected at the same station in having a more rounded disc, a shorter caudal fin, and a mottled colour pattern on the dorsal surface and on the ventral marginal bands. CSIRO H 6153-03 was almost black dorsally, and the ventral marginal band and the caudal fin very dark; black areas were also present ventrally on the tail. These atypical specimens, which could constitute another species, were excluded from the type series.

However, a concurrent study that aims to genetically barcode Australia’s fish species (Ward et al. 2005) failed to differentiate between the ‘normal’ colour form of the types and those with the atypical barred coloration discussed above (B. Innes & R. Ward pers. comm.). In the study, cytochrome oxidase subunit 1 (CO1) sequence divergences of U. kapalensis specimens (n = 13) were calculated using Kimura’s (1980) two-parameter model (MEGA version 3; Kumar et al. 2004) and found to be just 0.2-0.3% (B. Innes & R. Ward pers. comm.), well within acceptable intraspecific variation levels. The atypical specimens need further investigation.

The same genetic study distinguished the two Urolophus species possessing a bellshaped internasal flap ( U. kapalensis and U. paucimaculatus ), with a divergence of 9% (B. Innes & R. Ward pers. comm.).