Orectolobus halei Whitley 1940
Orectolobus halei Whitley, 1940 (Figs. 4-6, Table 1-2) Material examined Holotype. SAMA 2883 mm TL female (cast), type locality: St. Vincent Gulf, South Australia. Lost according to Eschmeyer (CD-Rom, 1998). Neotype (designated herein). AMS I 43628-002, 1700 mm TL, mature male, longline, type locali...
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Zenodo
2006
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Online Access: | https://dx.doi.org/10.5281/zenodo.6253842 https://zenodo.org/record/6253842 |
Summary: | Orectolobus halei Whitley, 1940 (Figs. 4-6, Table 1-2) Material examined Holotype. SAMA 2883 mm TL female (cast), type locality: St. Vincent Gulf, South Australia. Lost according to Eschmeyer (CD-Rom, 1998). Neotype (designated herein). AMS I 43628-002, 1700 mm TL, mature male, longline, type locality: the Hump, 3.3 nautical miles offshore between Garie Beach and Wollongong, 34° 14S, 151° 04E, 20-35 m, 9th June 2005, collector Charlie Huveneers and Jason Moyce. Other specimens examined. AMS I43628-001, 1285 mm TL, female; CSIRO H 6278- 01, 1775 mm TL, female; CSIRO H6278-02, 1869 mm TL, mature male; AMS I43628- 003, 1520 mm TL, immature male. All four specimens collected using longline at the Hump, 3.3 nautical miles offshore between Garie Beach and Wollongong, 34° 14S, 151° 04E, 20-35 m, 9th June 2005, collector Charlie Huveneers and Jason Moyce.AMS I43629- 001, 1140 mm TL, immature male, setline, Merimbula 50-100m from shore, 36° 54S, 149° 57E, 10-20 m, 24th April 2005, collector Charlie Huveneers, Shannon Corrigan and Shannon Fantham. Diagnosis A large species of Orectolobus with the following combination of characters: no warty tubercles on head or body; four groups of dermal lobes below and in front of eyes on each side of head; no dermal lobes on chin; nasal barbel closest to mouth branched; five to six lobes in second preorbital group (rarely four) with lobes at extremities usually longer and branched; broad branched postspiracular groups; two supraorbital knobs; base of anterior postspiracular lobe 3.28-3.69 in its distance from postorbital group, 1.36-2.36 in its distance from posterior postspiracular lobe; pelvic-fin insertion at first dorsal-fin midpoint; prepelvic length 2.40-3.13 times pelvic-anal space; pelvic-caudal space 1.04-1.25 times trunk width; teeth in upper jaw 25-28, those in medial row at symphysis rudimentary; spiral valve turns 29-32; precaudal vertebrae count 108-112. Light and dark brown coloration with nine darker brown, blotch-shaped saddles located dorsally; each saddle has conspicuous black edges. Description Body depressed anteriorly from snout to pelvic-fin origin, slightly firm dorsal musculature with relatively flaccid flanks; trunk depressed, broadest over midtrunk; body shape changing from depressed to compressed and tapering from pelvic-fin origin; dorsal musculature slightly elevated from flank musculature forming a small ridge from the fifth gill slit to pelvic-fin insertion, decreasing anteriorly to first dorsal-fin origin. Head broad, strongly depressed, somewhat oval in cross-section with truncate anterior when viewed from above, length 21.4 (21.0-21.8) % TL, 2.08 (2.08-2.76) times second dorsal-fin origin to anal-fin origin, height at gill level 8.5 (7.3-9.1) % TL, 1.74 (1.33-1.74) in pelvicfin midpoint to first dorsal-fin insertion; trunk width 21.7 (20.4-23.0) % TL; abdomen elongate, width 5.94 (5.26-6.34) % TL. Pectoral-pelvic space 19.3 (16.8-21.9) % TL, 0.90 (0.73-1.00) times head length; pelvic-anal space 2.10 (1.93-2.50) times anal-fin base; snout-vent length 0.99 (0.99-1.04) times vent-caudal length. Caudal peduncle absent, lower origin of caudal fin almost connected to anal-fin insertion, strongly compressed, oval in cross section at anal-caudal junction, caudal peduncle width 1.59 (1.33-1.64) in height. Snout short, narrowly rounded in lateral view, truncate in dorsoventral view, slightly rounded angles; preoral length 0.8 (0.8-1.2) % TL, 12.50 (8.33-12.50) in mouth width; prenarial length negligible. Eyes dorsal on head, small, slit-like, length 1.7 (1.5-1.8) % TL, 12.35 (12.35-12.99) in head length; supraorbital crest elevated over and behind eye; two knobs on supraorbital crest, posterior knob longer; weak supraorbital ridge extending above spiracle; subocular pocket 2.26-2.70 times eye length; interorbit weakly concave. Spiracles slit-like, oblique to horizontal axis, longer than eye, 1.99 (1.91-2.29) times eye length; anterior margin convex well elevated above weakly convex posterior margin; small eye spiracle space 0.4 (0.3-0.6) % TL; fold above spiracle anterior margin. Gill slits lateral on head, first three of similar length (2.2-3.0 % TL), fourth gill slit smaller, 0.94 (0.82-1.01) times third gill slit, last gill slit longest 1.17 (1.00-1.27) times first; last gill slit anterior to pectoral-fin midbase; pectoral-fin origin between second and third gill slit. Mouth subterminal, large 3.1 (2.9-3.3) % TL, horizontally expanded, broadly arched, width 10.7 (9.6-10.7) % TL, 3.47 (2.96-3.47) times its length, 4.76 (4.76- 5.26) in vent to caudal length; 0.96 (0.83-1.09) times dorsal-fin midpoint to pelvic-fin origin; upper labial furrows 4.3 (4.1-4.9) % TL, originating at ventral margin of nostrils; lower labial furrows longer 5.4 (4.6- 5.5) % TL, almost connected near symphysis of lower jaw. Nostrils small, widely separated, internarial space 5.4 (4.5-5.4) % TL, adjacent upper lip of mouth. Nasal barbel terminal on head, medial to nostrils, proboscis-like, rounded basally, tapering distally, length less than upper labial furrows; short flattened branched lobe at basal third of posterior margin; lateral nasal lobe broad, well elevated, subcircular, most expanded posteriorly. Fang-like teeth relatively large, long and pointed, not exposed when mouth closed. Upper jaw with rudimentary symphysial tooth recessible into upper lip and flanked distally by one larger symphysial on either side. Lower jaw with three rows of enlarged symphysials, their cusps subequal in length to each other and to those at symphysis in upper jaw; tooth cusps distal to symphysis decreasing sequentially in size; tooth shape varies distally from symphysis, first two to three teeth lack cusplets, one to two cusplets from the third or fourth parasymphysial on either side of the cusp on about four to seven teeth, distal cusplets more pronounced than medial ones, three to five most distal teeth generally lack cusplets on either side of cusp; teeth formula (n = 14): upper jaw (11-12) +1 + 1 + 1 + (11-12) = (25-27); lower jaw (8-11) + 3 + (8-10) = (19-24). Dermal lobes well developed; anterior preorbital group with three to four simple lobes, posterior lobe longest; posterior preorbital group with five to six lobes, longest lobes at extremities, anterior and second most posterior lobe longer and branched; combined distance across preorbital groups 8.3 (7.0-9.8) % TL; anterior and posterior postspiracular group with short, broader, branched single lobe, base width of anterior postspiracular lobe 1.6 (0.9-1.7) % TL, base width of posterior postspiracular lobe 1.7 (0.8-1.7) % TL; distance between prorbital group and anterior postspiracular lobe 3.5 (3.2-4) % TL, between postspiracular lobes 1.9 (1.9-2.5) % TL. Dermal denticles small, non-imbricated, crown shield-like, weakly tricuspidate at anterior end, weak ridge on all cusps at anterior end, rounded posterior end. Clasper elongate, extending well beyond tip of pelvic fins, inner length 17.8 (16.0-17.8) % TL, 6.40 (6.40-6.55) times width at base, tip bluntly pointed; four terminal cartilages: ventral terminal, accessory terminal cartilage (or spur), dorsal terminal 2 and dorsal terminal, approximate one-to-one ratio with all terminal cartilages, end-style of axial cartilage slightly calcified and fused with dorsal terminal. When terminal cartilages of clasper are open, spear-like extension near lateral side of axial 21.1 (18.5-24.7) % clasper shaft length. Dorsal fins similar in size and shape, triangular; anterior margins oblique; apices broadly rounded, first dorsal-fin apex slightly more rounded than second dorsal-fin apex; posterior margins vertical, very slightly convex to straight; inner margin parallel originating at level of pelvic-fin rear tip; second dorsal-fin height 8.4 (7.6-9.3) % TL, 0.99 (0.69-0.99) times pelvic-fin midpoint to second dorsal-fin origin; pre-first dorsal-fin length 48.9 (48.1-50.1) % TL, pre-second dorsal-fin length 61.2 (61.2-64.7) % TL; first dorsal-fin origin forward of pelvic-fin insertion (3.5 % TL); second dorsal-fin insertion anterior to anal-fin origin (0.7-0.8 % TL). Pectoral fin large, length 15.7 (13.4-15.7) % TL, 2.81 (2.81-3.01) times pelvic-fin inner margin length; base fleshy, anterior margin slightly convex; apex broadly rounded; posterior margin slightly convex; inner margin straight, free rear tip very broadly rounded; prepectoral length 16.2 (16.2-19.5) % TL; pectoral-pelvic space 19.3 (16.8-21.9) % TL. Pelvic fins moderately large, length 14.9 (12.0-14.9) % TL; anterior margin straight; apex very broadly rounded; posterior margin convex; inner margin straight, free rear tip broadly rounded; origin slightly anterior to first dorsal-fin origin, insertion first dorsal-fin midpoint; prepelvic length 44.1 (44.1-46.4) % TL, 2.51 (2.40-2.68) times pelvic-anal space; pelvic-anal space 17.6 (17.1-18.7) % TL, pelvic-caudal space 22.8 (21.9-26.57) % TL, 1.05 (1.03-1.26) times trunk width. Anal fin elongate, lobe-like, well developed, base 8.5 (7.5-8.9) % TL, 2.09 (1.55-2.20) times interdorsal space; anterior and inner margins almost parallel, anterior margin first slightly concave then slightly convex; apex very broadly rounded; posterior margin straight, much smaller than anterior margin; inner margin straight, free rear tip slightly rounded; origin slightly posterior to second dorsal-fin insertion, insertion slightly posterior to caudal-fin origin; anal-fin height 1.61 (1.45-1.85) in base length; second dorsal-fin origin to anal-fin origin 10.3 (8.2-10.3) % TL, second dorsal-fin insertion to anal-fin insertion 1.36 (1.11-1.48) times terminal caudal margin. Caudal fin long, strongly compressed; dorsal caudal margin length 21.0 (19.1-21.6) % TL, its origin slightly anterior to anal-fin insertion; upper lobe originating as a very low ridge, slightly distinguishable; anterior margin with a deep inflexion near its origin; outer rim straight and oblique; rounded apices; terminal caudal lobe fan-like; terminal caudal margin 6.2 (5.5-6.2) % TL. Vertebral counts (n = 7): pre-first dorsal count 54-55; pre-second dorsal count 78-80; precaudal count 108-112. Spiral valve whorl count: 29-32 (n = 32, based on discarded specimens). Coloration Body light and dark brown coloration with nine darker brown blotch-shaped saddles located dorsally; each saddle has conspicuous black edges followed by grayish coloration, light brown and gray freckle-like blotches between saddles; first saddle weakly visible, posterior to spiracle, anterior to second gill slit; second saddle at pectoral-fin base level, broader than long; posterior end of third saddle at pelvic-fin origin level, length similar to width, lighter brown saddle extending laterally; fourth saddle small, anterior to first dorsal -fin origin, overlapping with inflexion of first dorsal-fin; fifth saddle from first dorsal-fin midbase to slightly anterior to second dorsal-fin origin, extending laterally and ventrally below mid body, nearly connecting at ventral midline; sixth saddle from second dorsal-fin midbase to slightly anterior of caudal-fin origin, extending laterally and ventrally below mid body, nearly connecting at ventral midline; seventh saddle at origin of caudal fin, anterior to anal-fin insertion, longer than broad, extending laterally, not extending on lower lobe of caudal fin; eighth saddle on upper caudal lobe, longer than broad, extending laterally, not extending on lower lobe of caudal fin; ninth saddle slightly anterior to caudal -fin tip, extending laterally, not extending on lower lobe of caudal fin. Gray bluish blotches sometimes with black edges on saddles decreasing in number and size from fourth saddle. V-shaped pattern anterior to interorbit; white spot on posterior tip of spiracle. Underneath of head, trunk, abdomen and snout uniformly pale yellow, mouth and labial furrows with dark brown spots extending between posterior dermal lobe preorbital groups. Tail with three darker brown stripes on the flanks. Pectoral fins green brown with blotches, underneath yellow at base, increasing brown color towards posterior margins, slight light brown blotches and white freckles; pelvic fins brown gray with blotches, underneath yellow at base, increasing brown color towards posterior margins, slight light brown blotches and white freckles; anal fin green brown, similar to tail coloration; dorsal fins brown, darker brown where saddles occur, green gray blotches/spots; caudal fin green brown, darker brown where saddles occur. Remarks Orectolobus halei was previously synonymized with O. ornatus due to the similarity in morphology and color pattern. Whitley (1940) first mentioned this species as a subspecies of O. ornatus and only described it as differing from O. ornatus “in color pattern and the form of the tentacles around the head”. The holotype, lodged at the South Australian Museum, Adelaide (SAMA), has been missing since at least 1997. The designation of a neotype is required due to the following. First, the previous description was so incomplete as to make it impossible to reliably distinguish O. ornatus from O. halei. Secondly, there currently is a significant problem of misidentification between those two species within the targeted fishery for wobbegong sharks. Lastly, declining catches of wobbegong sharks strongly argue for a reliable means of identifying the target species. Orectolobus halei can be distinguished from O. ornatus by several measurements (Table 1) and the two species also differ in 11 specific ratios (Table 2). Orectolobus halei, which is regionally sympatric with S. tentaculatus, O. maculatus, O. wardi, O. hutchinsi, and two undescribed species of Orectolobus off WA, can be distinguished from these species by the combination of the number of dermal lobes, color pattern and the absence of tubercles. Orectolobus hutchinsi has slender unbranched postspiracular lobes (broad and branched in O. halei and O. maculatus) and a distinctive yellowish brown upper body coloration with well-defined, darker brown saddles containing paler markings that lacks whitish rings and blotches (unlike O. ornatus and O. maculatus) (Last et al., 2006). Sutorectus tentaculatus has large rounded tubercles on both the head and body, not present in the adults of other members of the family Orectolobidae. Orectolobus maculatus has six to ten dermal lobes, O. wardi has unbranched nasal barbels, whereas O. halei has five dermal lobes and branched nasal barbels. Orectolobus wardi has a simple color pattern with fewer dark spots, while O. maculatus and O. halei have a more elaborate pattern of variegated spots and saddles. Orectolobus maculatus has white O- shaped spots and white blotches that are absent in O. halei. Size To at least 2060 mm TL; males mature at 1684-1819 mm TL, females mature at 1605- 1871 mm TL (Huveneers unpublished data). Distribution Temperate Australia, from Southport (27° 06S, 153° 26E), Qld, to Norwegian Bay (22° 54S, 113° 59E), WA. Southern records to Flinders Island (40° 19S, 147° 48E), Bass Strait. : Published as part of Charlie Huveneers, 2006, Redescription of two species of wobbegongs (Chondrichthyes: Orectolobidae) with elevation of Orectolobus halei Whitley 1940 to species level., pp. 29-51 in Zootaxa 1284 on pages 32-43 |
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