Tubbia tasmanica Whitley

Last, Peter R., Daley, Ross K. & Duhamel, Guy, 2013, A review of the rudderfish genus Tubbia (Stromateoidei: Centrolophidae) with the description of a new species from the Southern Hemisphere, Zootaxa 3616 (5), pp. 461-477 : 471-476

Tubbia tasmanica Whitley

Tasmanian Rudderfish

Figs 1 B, 2B, 4, 5B, 6; Tables 1 – 3

Tubbia tasmanica Whitley, 1943: 179 , Fig. 9. Holotype: AMS IB.1148, off Tasmania, Australia. Schedophilus huttoni (not Waite): Haedrich, 1967, 62 (misidentification).

Holotype. AMS IB 1148, 73 mm SL, off Maria Island, Tasmania, 42º42′ S, 148º34′ E, 50 m, 22 Jan 1941.

Other material. 52 specimens. AMS I 45431 –001, 276 mm SL, Pedra Branca seamount, Tasmania, 44º56′ S, 147º16′ E, 525–650 m, 28 Nov 1992; AMS I 45441 –002, 350 mm SL, south Tasman Sea, Tasman Sea, 40º58′ S, 164º24′ E, 590–763 m, 19 Jun 2009; CSIRO H 495, 390 mm SL, South Tasman Rise, Tasmania, 46º58′ S, 148º09′ E, 1020–1070 m, 2 Apr 1986; CSIRO H 1600–03, 354 mm SL, South Tasman Rise, Tasmania, 47º40′ S, 148º02′ E, 1200 m, 22 Mar 1986; CSIRO H 1603–01, 276 mm SL, South Tasman Rise, Tasmania, 47º05′ S, 148º27′ E, 1060–1090 m, 2 Apr 1986; CSIRO H 1615–02, 364 mm SL, off Cape Sorell, Tasmania, 42º23′ S, 144º38′ E, 1380–1400 m, 18 May 1986; CSIRO H 2667–01, 311 mm SL, off Studland Bay, Tasmania, 40º49′ S, 143º37′ E, 845–890 m, 8 Mar 1989; CSIRO H 2667–02, 323 mm SL, off Studland Bay, Tasmania, 40º49′ S, 143º37′ E, 845–890 m, 8 Mar 1989; CSIRO H 2812–03, 325 mm SL, South Tasman Rise, Tasman Sea, 47º34′ S, 148º38′ E, 1115–1150 m, 16 Jan 1992; CSIRO H 2815–01, 277 mm SL, South Tasman Rise, Tasman Sea, 47º23′ S, 148º52′ E, 1110–1180 m, 1 Feb 1992 CSIRO H 2830–01, 288 mm SL, South Tasman Rise, Tasman Sea, 47º23′ S, 148º50′ E, 1120–1145 m, 3 Feb 1992; CSIRO H 2831–01, 269 mm SL, South Tasman Rise, Tasman Sea, 47º37′ S, 148º13′ E, 1155–1164 m, 11 Feb 1992; CSIRO H 3272–01, 268 mm SL, off Maria Island, Tasmania, 42º45′ S, 148º16′ E, 85–96 m, 5 Jun 1992; CSIRO H 3273–01, 265 mm SL, off Tasmania, 43º19′ S, 139º40′ E, 16 Jul 1992; CSIRO H 3274–01, 269 mm SL, off Tasmania, 44º42′ S, 142º27′ E, 14 Dec 1992; CSIRO H 3563–01, 321 mm SL, Pedra Branca seamount, Tasmania, 44º46′ S, 147º08′ E, 660–785 m, 28 Nov 1992; CSIRO H 3563–02, 302 mm SL, Pedra Branca seamount, Tasmania, 44º46′ S, 147º08′ E, 660–785 m, 28 Nov 1992; CSIRO H 3584–01, 231 mm SL, Tasman Plateau, off Tasmania, 45º00′ S, 142º30′ E, 20 Nov 1993; CSIRO H 3585–01, 209 mm SL, Tasman Plateau, off Tasmania, 45º04′ S, 142º44′ E, 20 Nov 1993; CSIRO H 3967–01, 392 mm SL, Pedra Branca seamount, Tasmania, 44º12′ S, 147º18 E, 650–775 m, 12 Nov 1992; CSIRO H 3967–03, 392 mm SL, Pedra Branca seamount, Tasmania, 44º12′ S, 147º18′ E, 650–775 m, 12 Nov 1992; CSIRO H 3967–04, 362 mm SL, Pedra Branca seamount, Tasmania, 44º12′ S, 147º18′ E, 650–775 m, 12 Nov 1992; CSIRO H 3968–02, 402 mm SL, Pedra Branca seamount, Tasmania, 44º20′ S, 147º22 E, 705–725 m, 24 Nov 1992; CSIRO H 4157–03, 332 mm SL, Pedra Branca seamount, Tasmania, 44º11′ S, 147º13′ E, 715–900 m, 13 Nov 1992; CSIRO H 6853–12, 306 mm SL, south Tasman Sea, Tasman Sea, 40º31′ S, 158º16′ E, 591–768m, 18 Jun 2008; CSIRO H 6969–04, 292 mm SL, south Tasman Sea, Tasman Sea, 40º57′ S, 164º25′ E, 763–912 m, 19 Jun 2009; CSIRO H 6978–05, 363 mm SL, south Tasman Sea, Tasman Sea, 40º58′ S, 164º24′ E, 590–763 m, 19 Jun 2009; CSIRO H 6978–06, 351 mm SL, south Tasman Sea, Tasman Sea, 40º58′ S, 164º24′ E, 590–763 m, 19 Jun 2009; CSIRO H 6979–02, 343 mm SL, south Tasman Sea, Tasman Sea, 40º55′ S, 166º53′ E, 610–800 m, 18 Jun 2009; CSIRO H 6979–03, 314 mm SL, south Tasman Sea, Tasman Sea, 40º55′ S, 166º53′ E, 610–800 m, 18 Jun 2009; CSIRO H 6979–04, 324 mm SL, south Tasman Sea, Tasman Sea, 40º55′ S, 166º53′ E, 610–800 m, 18 Jun 2009; CSIRO H 6979–05, 323 mm SL, south Tasman Sea, Tasman Sea, 40º55′ S, 166º53 E, 610–800 m, 18 Jun 2009; CSIRO H 7130–01, 282 mm SL, Pedra Branca seamount, Tasmania, 44º11′ S, 147º21′ E, 525–650 m, 13 Nov 1992; CSIRO T 33, 378 mm SL, off King Island, Tasmania, Oct 1983; CSIRO T 45, 355 mm SL, off King Island, Tasmania, 40º26′ S, 143º19′ E, 920–940 m, 12 Oct 1983; CSIRO T 1865–01, 378 mm SL, off Trial Harbour, Tasmania, 41º53′ S, 144º29′ E, 923–977 m, 5 Jul 1983; CSIRO T 1892–01, 222 mm SL, South Tasman Rise, Tasmania, 47º10′ S, 147º52 E, 15–200 m, 2 Jan 1980; MNHN 1998–0465, 407 mm SL, St Paul and Amsterdam Islands, Indian Ocean, 38º 0 6′ S, 77º 45′ E, 754–809 m, 7 Jul 1996; NMNZ P. 0 0 7613, 110 mm SL, Puysegur Bank, New Zealand, 46º 21′ S, 165º 31′ E, 167 m, 16 Jan 1976; NMNZ P. 0 14554, 365 mm SL, Challenger Plateau, New Zealand, 40º 11′ S, 168º 50′ E, 855–857 m, 28 Aug 1983; NMNZ P. 0 14734, 403 mm SL, Challenger Plateau, New Zealand, 40º 18′ S, 169º 0 8′ E, 862–864 m, 18 Oct 1983; NMNZ P. 0 15814, 386 mm SL, off Canterbury Bight, New Zealand, 44º 37′ S, 173º 26′ E, 772–790 m, 11 Jun 1984; NMNZ P. 0 15932, 310 mm SL, Challenger Plateau, New Zealand, 40º 0 0′ S, 167º 42′ E, 1064–1082 m, 8 Jul 1984; NMNZ P. 0 18859, 84 mm SL, off Dunedin, New Zealand, 45º 59′ S, 170º 33′ E, 48 m, 15 Jan 1982; NMNZ P. 0 25990, 172 mm SL, Campbell Plateau, New Zealand, 51º 43′ S, 174º 0 6′ E, 779–789 m, 17 Aug 1990; NMNZ P. 0 27112, 194 mm SL, Chatham Rise, New Zealand, 44º 23′ S, 179º 40′ W, 910–1000 m, 10 Nov 1990; NMNZ P. 0 27973, 334 mm SL, Campbell Plateau, New Zealand, 48º 32′ S, 169º 11′ E, 699–712 m, 18 Dec 1991; NMNZ P. 0 29664, 302– 357 mm SL, Snares Shelf, New Zealand, 48º 51′ S, 166º 26′ E, 540–560 m, 23 Oct 1992; NMNZ P. 0 36059, 143 mm SL, Puysegur Trench, New Zealand, 45º 44′ S, 165º 33′ E, 100 m, 12 May 1998; NMNZ P. 0 41938, 69 mm SL, off Timaru, New Zealand, 44º 16′ S, 171º 30′ E, 20–23 m, 5 Jun 1999; NMV A 26359–001, 269 mm SL, Pedra Branca seamount, Tasmania, 44º56′ S, 147º16′ E, 650– 525 m, 28 Nov 1992; NMV A 26360–001, 323 mm SL, south Tasman Sea, Tasman Sea, 40º58′ S, 164º24′ E, 763– 590 m, 19 Jun 2009.

Diagnosis. A species of Tubbia with the following combination of characters: head of adult moderately compressed with a strongly arched interorbit (its width 6.4–7.9% SL in specimens exceeding 300 mm SL); nostrils small, width of posterior nostril 14–26 times in postorbital head length in adults (exceeding 300 mm SL); eye small in adults (diameter 5.2–6.3% SL) and well removed from dorsal margin of head (closest horizontal distance 1.5–1.9 times in diameter of orbit); jaws relatively small, head length 2.5–2.8 times length of lower jaw; head pores dense; caudal peduncle relatively broad at insertion of anal fin, width 3.5–4.7% SL in juveniles (less than 110 mm SL), 5.3–6.1% SL in adults (exceeding 300 mm SL); vertebral centra 40–43.

Size. Reaches at least 407 mm SL based on material form this study; recorded to 371 mm SL by McDowall (1979).

Distribution. Widely distributed in the temperate mesopelagic zone of the Southern Hemisphere, off Australia, New Zealand, and St Paul Island (southwestern Indian Ocean), but probably more widespread; occurs over continental slopes as well as offshore seamounts and plateaus ( Fig. 7 ). A record of T. tasmanica from Natal (southwestern Indian Ocean) may be of T. stewarti and warrants further investigation. Most juveniles (68–268 mm SL) were taken in the epipelagic zone at 15–200 m; larger individuals (172–402 mm SL) for which depth data exist were caught by midwater and demersal trawl gear at 52–1400 m.

Remarks. The two species of Tubbia are very similar to each other and it is not surprising that past authors failed to identify a second species. Features used in the literature to define T. tasmanica equally define T. stewarti , and no apomorphic character (with the possible exception of vertebral counts) has been identified to diagnose either species. As a consequence, T. tasmanica was not redescribed herein. Rather, a composite of characters distinguishing the two species are given in the diagnoses and these were discussed in the Comparisons section of T. stewarti . In summary, T. tasmanica has a more compressed head, less slender body, more convex interorbit, shorter jaws, fewer dense head pores, relatively smaller eyes and nostrils, a broader caudal peduncle and fewer vertebral centra, than T. stewarti .

There are also important molecular differences between the two species (see Fig. 8 ). A neighbour joining tree, including Tubbia species and their close relatives, identified individuals into their six respective taxa with good bootstrap support (>70%): i.e. Tubbia tasmanica , T. stewarti , Schedophilus huttoni , S. maculatus , S. velaini and S. labyrinthicus . Intragroup variation within five of the groups was low and Bootstrap values exceeded 85% supporting morphological evidence that these groups represent single species. Some variability was found in the S. labyrinthicus group which comprises two genetically distinct sympatric forms in New Zealand waters.

Most importantly, the molecular analysis distinguished the two species of Tubbia supporting findings from an earlier muscle protein analysis (Daley et al., 1997). Our analysis is not fully reliable from a phylogenetic aspect as it uses only a single molecular marker, but the clustering of S. huttoni with Tubbia away from the 3–4 other ‘firmbodied’ Schedophilus species, supports earlier suggestions that the genus Schedophilus is polyphyletic (McDowall, 1979; Bolch et al., 1994). Also, conspecificity of Schedophilus velaini and S. labyrinthicus has been proposed (Andrew et al., 1995; Eschmeyer & Fricke, 2012) but these taxa appear to be distinct at the species level.

Key to species of the genus Tubbia

1. Head of adult robust with a relatively broad and moderately arched interorbit; nostrils large, width of posterior nostril 10–12 times in postorbital head length in adults (exceeding 300 mm SL); eye large in adults and close to dorsal margin of head (closest horizontal distance 2.0–3.2 times in diameter of orbit); jaws large, head length 2.2–2.5 times length of lower jaw; caudal peduncle narrow at insertion of anal fin, width 2.4–3.0% SL in juveniles (less than 110 mm SL), 3.3–5.2% SL in adults (exceeding 300 mm SL); vertebral centra 44–45................... Tubbia stewarti sp. nov. ( Australia and New Zealand)

- Head of adult moderately compressed with a strongly arched; nostrils small, width of posterior nostril 14–26 times in postorbital head length in adults (exceeding 300 mm SL); eye small in adults and well removed from dorsal margin of head (closest horizontal distance 1.5–1.9 times in diameter of orbit); jaws small, head length 2.5–2.8 times length of lower jaw; caudal peduncle broad at insertion of anal fin, width 3.5–4.7% SL in juveniles (less than 110 mm SL), 5.3–6.1% SL in adults (exceeding 300 mm SL); vertebral centra 40–43..... Tubbia tasmanica Whitley, 1943 ( Australia, New Zealand, and St Paul Island) Acknowledgments

This research was facilitated by a grant from the New Zealand Foundation for Research, Science and Technology (Biosystematics of NZ EEZ Fishes programme, FRST contract MNZX0203; project leader Dr C. Roberts), as well as the CSIRO Wealth from Oceans Flagship. Collection staff at various museums, in particular Patrice Provost (NMHN), Mark McGrouther (AMS), and Andrew Stewart and Clive Roberts (NMNZ), kindly made valuable loan material available for this study; Carl Struthers (NMNZ) produced X-rays of NMNZ material and figures 1A, 3C, 4B & C and 6, and Jeremy Barker (NMNZ) created the map. Alastair Graham (ANFC) assisted with materials sections and John Pogonoski (ANFC) compiled meristic details from CSIRO radiographs. Sharon Appleyard (CSIRO) provided invaluable assistance with the molecular analysis. Carlie Devine (ANFC) prepared digital images of material used in the figures. The authors wish to thank the journal editor and reviewers of the manuscript for their useful comments.

Figures

FIGURE 1. Lateral views of adult: A, Tubbia stewarti sp. nov., holotype NMNZ P. 0 33110, 434 mm SL (fresh); B, T.

FIGURE 7. Map of the Australasian region showing the distributions of Tubbia stewarti (encircled diamonds) and T. tasmanica (triangles); holotypes of Tubbia stewarti (encircled cross) and T. tasmanica (encircled star).

FIGURE 8. Neighbour-joining tree of nucleotide sequence divergence at the barcoding region of the COI gene for species of Tubbia and Schedophilus (Centrolophidae) from the Southern Hemisphere. Scale bar represents 1 % K 2 P following 10000 bootstraps. Tissue sample numbers relate to those present in the Barcode of Life Database (www. barcodinglife. org).