Chaunax russatus, Ho, Hsuan-Ching, Roberts, Clive D. & Stewart, Andrew L., 2013

Ho, Hsuan-Ching, Roberts, Clive D. & Stewart, Andrew L., 2013, A review of the anglerfish genus Chaunax (Lophiiformes: Chaunacidae) from New Zealand and adjacent waters, with descriptions of four new species, Zootaxa 3620 (1), pp. 89-111 : 105-109

Chaunax russatus sp. nov.

New English Name: Red Coffinfish ( Figures 6 B, 11A–B, 12A–B, Table 2 )

Holotype. NMNZ P.038059 (170 mm), Kaikoura Canyon, 43º0.09'S, 173º53.85'E, F/V San Tongariro, stn. OBS 1451/032, 821–1030 m, bottom trawl, 29 Jan. 2001, coll. A. Sealey and S. Mulgrew.

Paratypes. 24 specimens, 115–233 mm SL. New Zealand: CSIRO H 7374–01, 140 mm (ex NMNZ P. 041743) Ritchie Banks off Napier, Hawke Bay, 39°42.1'S, 178°13'E, 900–1150 m, 8 Jun 2005, D. Prendergast & J. Plowmen. NMMB–P10461 (ex NMNZ P.014899, 146 mm, Uruti High, off Cape Palliser, 41º15.5'S, 176º31'E, 1200 m, trawl, 13 Dec. 1983, coll. A. Adie. NMV A.30941–001, 172 mm SL (ex NMNZ P.038060), taken with holotype, Kaikoura Canyon. NMNZ P.009647, 163 mm, NE of Chatham Islands, 42º52.2'S, 176º0.8'W, R/V Wesermunde, stn. WES 8001/052, 889–907 m, 23 Jul. 1980. NMNZ P. 010502, 170 mm, N Chatham Rise, 42º52'S, 175º48.3'W, R/V Wesermunde, stn. WES 8001/018, 945 m, 14 Jul. 1980. NMNZ P. 011445, 140 mm, F/V Kalinovo, stn. K8101/015, 35º14.4'S, 175º19.55'E, E of Poor Knights Islands, 875–900 m, bottom trawl, 22 Nov. 1981. NMNZ P. 012846, 198 mm, F/V Kaltan, stn. KTN 8201/006, 42º47.6'S, 177º12.6'W, N Chatham Rise, 980 m, 3 Aug. 1982. NMNZ P. 012871, 180 mm, F/V Kaltan, stn. KTN 8201/045, 42º57.45'S, 175º35.6'W, N Chatham Rise, 860 m, 10 Aug. 1982. NMNZ P.014899, 145 mm, 41º15.5'S, 176º31'E, Uruti High, off Cape Palliser, 1200 m, trawl, 13 Dec. 1983, coll. A. Adie. NMNZ P.015453, 143 mm, 41º17.4'S, 176º33.7'E, Uruti Depression, S Hikurangi Trench, R/V James Cook, stn. JCO 8406/026, 780–840 m, bottom trawl, 5 Apr. 1984. NMNZ P. 031012, 233 mm, R/V Wesermunde, stn. WES 8001/005, 42º48.8'S, 176º35.8'W, E Chatham Rise, 930–950 m, 10 Jul. 1980. NMNZ P.036063, 193 mm, 42º41.5'S, 177º11'E, NE Chatham Rise, F/V San Torshavn, stn. OBS 1172/024, 950–970 m, bottom trawl, 2 Dec. 1998, coll. G. Marks & L. Summerfield. NMNZ P.037188, 180 mm, 37º4.6'S, 176º41.2'E, Mayor Channel, Raukumara Plain, F/V Ocean Fresh, stn. OBS 1337/011, 1049–1071 m, bottom trawl, 27 Mar. 2000, coll. D. Wrightson. NMNZ P.037200, 115 mm, 38º0.0'S, 174º00.0'E, off Manakau, Auckland, F/V San Rakaia, 900 m bottom trawl, B. Adams, 26 Jun. 2000. NMNZ P.038060, 172 mm, 43º0.09'S, 173º53.85'E, Kaikoura Canyons, F/V San Tongariro, stn. OBS 1451/032, 821–1030 m, bottom trawl, 29 Jan. 2001, coll. A. Sealey & S. Mulgrew. NMNZ P. 040706, 155 mm, 37º41'S, 179º21'E, off East Cape, F/V San Rakaia, bottom trawl, 29 May 2004. NMNZ P. 041328, 163 mm, 37º13.65'S, 177º15.215'E, Whakatane Seamount, SW of Kermadec Ridge, R/V Tangaroa , stn. TAN 0413/062, 788–807 m, beam trawl, 11 Nov. 2004. NMNZ P. 041743, 140 mm, 39º42.1'S, 178º13'E, Ritchie Banks off Napier, 900–1150 m, 8 Jun. 2005. NMNZ P. 042410, 187 mm, 43º2.3'S, 174º54.55'W, E Chatham Rise, F/V San Waitaki, stn. OBS 2247/022, 920–938 m, bottom trawl, 3 May 2006, coll. R. Cropp & R. Fraser. NMNZ P. 042411, 168 mm, 43º2'S, 175º6'W, E Chatham Rise, F/V San Waitaki, stn. OBS 2247/024, 915–917 m, bottom trawl, 4 May 2006, R. Cropp & R. Fraser. NMNZ P.046333, 143 mm, 34º1.45'S, 168º7.6'E, seamount at middle of West Norfolk Ridge, stn. OBS 2170/054, 808–954 m, bottom trawl, 17 Oct. 2005, coll. T. Turton. USNM 406854, 168 mm SL, (ex NMNZ P. 042411), east Chatham Rise, 43°2.0'S, 175°6.0'W, F/V San Waitaki, stn. OBS 2247/024, 915–917 m, bottom trawl, 4 May 2006, R. Cropp & R. Fraser. Outside NZ EEZ: NMNZ P. 020312, 2, 175– 179 mm, 37º28.3'S, 167º33.4'E, NW Challenger Plateau, Lord Howe Rise, F/V Albert Sanford, stn. OBS 0033/023, 700–888 m, bottom trawl, 28 Sep. 1986, coll. R. Stewart. NMNZ P.023482, 2, 185– 196 mm, 39º30.25'S, 167º47.55'E, W Challenger Plateau, F/V Oyang 7, stn. OBS 0284/002, 814–868 m, bottom trawl, 1 Sep. 1988, coll. P. Sharples. NMNZ P. 041711, 165 mm, 35º51'S, 165º1.2'E, S Lord Howe Rise, F/ V Korvet 358, stn. OBS 1357/006, 948–949 m, bottom trawl, 14 May 2000, G. Anderson & S. Beatson.

Non-types. 31 specimens, 61–195 mm SL. NMNZ P.008426, 110 mm, 42º50'S, 176º36'W, Chatham Rise, R/V Wesermunde, stn. WES 7903/055, 902–930 m, 5 Jun. 1979. NMNZ P.008452, 238 mm, 42º50.5'S, 176º46.5'W, Chatham Rise, R/V Wesermunde, stn. WES 7903/041, 855–879 m, 2 Jun. 1979. NMNZ P.009646, 245 mm, 42º53.5'S, 176º 12.4'W, N. of Chatham Island, R/V Wesermunde, stn. WES 8001/049, 880–890 m, 22 Jul. 1979. NMNZ P.009832, 72 mm, 37º10.85'S, 177º38.35'E, W. of White Island, R/V Tangaroa , stn. NZOI BS844/O590, 685– 705 m, beam trawl, 23 Jan. 1981. NMNZ P.009862, 95 mm, 38º11.45'S, 170º22.15'E, NE Challenger Plateau, R/V James Cook, stn. JCO 8102/041, 851 m, bottom trawl, 29 Jan. 1981, NMNZ P. 010128, 115 mm, 37º42.1'S, 173º53.6'E, SE of Aotea Seamount, off Raglan, R/V James Cook, stn. JCO 8106/064, 841–848 m, trawl, 25 Apr. 1981. NMNZ P. 010512, 2, 110– 160 mm, 42º51.95'S, 179º46.4'W, NW of Chatham Islands, R/V James Cook, stn. JCO 8101/004, 802–816 m, trawl, 10 Jan. 1981. NMNZ P. 012876, 170 mm, 42º54.65'S, 175º53.75'W, N Chatham Rise, F/V Kaltan, stn. KTN 8201/032, 840– 840 m, bottom trawl, 8 Aug. 1982. NMNZ P. 012973, 195 mm, 43º12.65'S, 174º20.55'W, NE Chatham Rise, F/V Kaltan, stn. KTN 8201/070, 970 m, bottom trawl, 14 Aug. 1982. NMNZ P.014022, 82 mm, 35º55'S, 174º20'E, 22 miles N of Cape Brett, 731–732 m, 22 Nov. 1962. NMNZ P.014157, 140 mm, 39º33.1'S, 170º58.95'E, Central Challenger Plateau, R/V James Cook, stn. JCO 8307/031, 837–841 m, bottom trawl, 6 Jul. 1983. NMNZ P.015766, 100 mm, 37º26.9'S, 173º58.8'E, SW of Manukau Harbour, R/V James Cook, stn. JCO 8409/017, 720–800 m, bottom trawl, 28 May 1984. NMNZ P. 031132, 156 mm, 40º45'S, 174º45'E, off D'Urville Island, depth unknown setline, Jun. 1994. NMNZ P. 031355, 160 mm, Challenger Plateau, F/V San Manukau, 39º54'S, 168º07'E, 850– 865 m. NMNZ P.037235, 80 mm, 36º29.98'S, 176º30.155'E, E of Alderman Islands, R/V Kaharoa, stn. KAH 9907/053, 990–1100 m, bottom trawl, 5 Jun. 1999. NMNZ P.037968, 143 mm, 42º48.2'S, 179º11.05'E, N central Chatham Rise, F/V Kap Farvel, stn. OBS 1571/081, 1070–1100 m, bottom trawl, 26 Oct. 2001, coll. D. Wrightson. NMNZ P.038417, 61 mm, 41º30.5'S, 170º33.45'E, Challenger Plateau, NW of Cape Foulwind, F/V Sureste 709, stn. OBS 1656/010,512– 592 m, midwater trawl, 24 Jun. 2002, coll. C. Loveridge & T. Brunning. NMNZ P.038418, 65 mm, 41º32.3'S, 170º25.2'E, Challenger Plateau, NW of Cape Foulwind, F/V Sureste 709, stn. OBS 1656/031, 617–650 m, midwater trawl, 2 Jul. 2002. NMNZ P.038765, 77 mm, Cameron Rattray and Geoff Dolan, F/V Sureste 700, stn. OBS 1662/019, 42º01'S, 170º13.25'E, Challenger Plateau, SW of Cape Foulwind, 721–787 m, bottom trawl, 13 Jul. 2002, coll. C. Loveridge & T. Brunning. NMNZ P. 041264, 85 mm, 42º5.7'S, 170º18.3'E, SE Challenger Plateau, SW of Cape Foulwind, F/V Melilla 203, stn. OBS 1969/082, 643–680 m, bottom trawl, 11 Sep. 2004, coll. L. Dalton & S. Thickpenny. NMNZ P. 041456, 105 mm, 43º26.95'S, 173º56.025'W, NE of Chatham Islands, R/V Tangaroa , stn. TAN 0408/043, 1199–1200 m, bottom trawl, 22 Jul. 2004. NMNZ P. 041841, 2, 69– 90 mm, 37º13.65'S, 177º15.215'E, Whakatane Seamount, SW Kermadec Ridge, R/V Tangaroa , stn. TAN 0413/062, 788–807 m, beam trawl, 11 Nov. 2004. Outside NZ EEZ: NMNZ P.009863, 100 mm, 37º50.9'S, 167º20.75'E, W Challenger Plateau, R/V James Cook, stn. JCO 8102/017, 866–878 m, trawl, 25 Jan. 1981. NMNZ P.014552, 100 mm, 37º28.9'S, 167º45.95'E, NW Challenger Plateau, F/V Arrow, stn. ARR 8301/061, 878–887 m, 9 Sep. 1983. NMNZ P.025723, 3, 112– 156 mm, 36º18.55'S, 164º51.6'E, S Lord Howe Rise, F/V Tampen, stn. OBS 0429/030, 937–943 m, bottom trawl, 15 Jul. 1990, coll M. Nedd. NMNZ P. 032501, damaged, 40º52'S, 165º02'W, Valerie Guyot, Louisville Ridge, 670–850 m, 12 Jul. 1995, coll. M. Marinovich. NMNZ P.037204, 155 mm, 37º22.35'S, 167º39.65'E, S Lord Howe Rise, F/V Baldur, stn. OBS 1281/017, 950–951 m, bottom trawl, 19 Oct. 1999, coll. N. Mitchell.

Diagnosis. A member of the C. abei -species group with a broad illicial trough that is wider than the eye pupil diameter, and a uniformly deep red body. It can be further distinguished from other congeners in having modally one spine on each side of lateral-line neuromast; modally 12 pectoral-fin rays; wide and stout caudal peduncle; short and stout illicium; large esca with numerous bright red cirri; and a greyish gill chamber and gill arches. Gill rakers: GRi = 17–18 (3–4+13–15); GRii = 14–15; GRiii = 14–15; GRiv = 12. Lateral-line neuromast counts: AB = 11–12 (modally 12); AC = 8; BB' = 4–5 (4); BD = 2–3 (2); CD = 6–7 (7); EF = 4–5 (4); FG = 4–5 (4); GH = 11–14 (13); BI = 32–39.

Description. Morphometric and meristic data are given in Table 2 . Head length 2.4 (2.3–2.9) in SL; head width 5.4 (5.1–5.7) in SL, 2.3 (2.0–2.3) in HL; predorsal length 2.1 (2.0–2.3) in SL; pre-gill opening length 1.5 (1.5–1.7); pre-preopercular length 3.5 (3.3–4.0) in SL, 1.5 (1.4–1.5) in HL; upper jaw 5.0 (4.4–5.2) in SL, 2.1 (1.8–2.2) in HL; illicial length 8.1 (7.8–11.2) in HL; illicial trough length 5.1 (4.7–6.7) in HL; eye diameter 4.8 (4.5–5.5) in HL; post-dorsal fin length 4.9 (4.5–5.6) in SL, 1.9 (1.7–2.3) in HL; post-anus length 2.6 (2.4–3.6) in SL, 1.1 (1.0–1.4) in HL; post-anal fin length 5.6 (5.4–6.9) in SL, 2.3 (2.0–2.9) in HL; caudal peduncle depth 5.0 (4.2–5.5) in HL; caudal fin length 3.6 (3.2–3.8) in SL, 1.5 (1.2–1.5) in HL.

Head globular, skull slightly elevated posteriorly; trunk cylindrical, slightly compressed, tapering posteriorly; skin thin, loose and flaccid; interorbital space broad; caudal peduncle short and stout, rather depressed, tapering posteriorly. Eyes rounded, directed dorsolaterally, covered by dermal membrane broadly connected to adjoining skin, forming clear “window”.

Illicium short and stout; esca large, with large central tongue bearing many stout whitish and pinkish cirri ( Fig. 6 B); second dorsal-fin spine close to illicium, embedded under skin; third dorsal-fin spine situated at about midpoint of pre-dorsal distance, embedded under skin. Illicial trough very wide, rounded in outline, relatively flattened, its width greater than diameter of eye pupil.

Two nostrils anterior to each eye, anterior nostril surrounded by flesh membrane, posterior part higher than anterior part, posterior nostril a simple round hole; mouth wide, terminal, its opening nearly vertical; lower jaw slightly protruding in front of upper jaw; maxilla tapering above, broad below; blunt symphyseal spine on lower jaw.

A broad transparent membrane on first gill arch; first ceratobranchial broadly connected to opercular wall; gill filaments present on second to fourth gill arches, two row of gill filaments (holobranch) on second and third gill arches, one single row of gill filaments (hemibranch) on fourth gill arch; those on inner row of third arch and fourth gill arch about one–third length of those of other; inner surface of fourth gill arch completely connected to body. A single row of 17–18 rakers on first gill arch, 3–4 on upper limb and 13–15 on lower limb, 14–15 paired rakers on2nd arch, 14–15 paired rakers on 3rd arch and a single row of 12 rakers on 4th arch.

Interspaces of lateral-line neuromast complex slightly longer than its width; 1–3 (modally 1) pairs of slender spines bridging each neuromast ( Figs. 1 B, 12A).

Skin thin, tips of pectoral-fin rays and pelvic-fin rays free from membrane, dermal spinules long and slender, simple ( Fig. 12 B), covering entire body, except eye window, outer half of pectoral fins, entire anal fin and membranes between rays of fins. Large naked area in front of illicial trough with scattered spinules in some.

Teeth in both jaws slender, fang-like; 5–8 irregular rows in upper jaw, their length gradually in creasing from outer to inner row, those in inner row slightly longer than those of outer rows; 5–8 irregular rows in lower jaw, their length gradually increasing from outer to inner row, those of inner row longest. Teeth on vomer small, forming two wide bands, in about 3 rows, distinctly separated by a small intermediate space; those on palatine small, forming elongate patch, close to outer end of vomerine teeth.

Dorsal-fin rays III, 12; first ray shortest, about half length of second ray; last two rays branched. Pectoral fin fan-shaped, with 11–13 rays (mainly 12), 4th or 5th ray longest, rays gradually shorter from 6th to last ray. Anal fin with 6–7 rays, first ray shortest, first and second simple, 3rd or 4th to last branched. Caudal fin truncate, with 9 rays, lowermost shortest, close to ray above, second to seventh rays branched, remaining 3 simple.

Colouration. Fresh ( Fig. 11 A–B): bright red with scattered patches of darker pigment; lateral cirri bright red. Preserved: uniformly creamy white with some fuzzy patches of dark pigment usually present; inner part of mouth cavity and gill chamber including gill arches blackish.

Distribution. Widely distributed on the continental slopes of the North Island and the northern South Island of New Zealand north of the subtropical convergence, from the southern Lord Howe Rise, West Norfolk Ridge, southern Kermadec Ridge, along the northern slope of the Chatham Rise to east of the Chatham Islands, and the Louisville Ridge ( Fig. 8 ). Bathymetric range 512–1200 m.

Etymology. From the Latin “ russatus ” – clothed in red, in reference to the uniform bright red colour of the body and fins.

Remarks. Chaunax russatus sp. nov. is most similar to C. mulleus when preserved. They have similar lateralline neuromast counts and squamation, and their proportions overlap. Chaunax russatus sp. nov. differs from C. mulleus in having a very large illicial trough ( Fig. 6 B), usually wider than the diameter of the eye pupil (vs. narrower), a uniformly deep red colour (vs. pinkish with red tips of the pectoral and pelvic fins) and a naked area in front of the illicial trough (vs. a narrow band of dermal spinules).

Figures

FIGURE 1. Micrographs of lateral-line neuromast complex of Chaunax species. A. Chaunax penicillatus, ASIZP 58059. B. Chaunax russatus sp. nov., BSKU 44629. Taken by SEM at Biodiversity Research Center, Academia Sinica, Taipei.

FIGURE 6. Dorsal view of illicial trough area showing relative size of trough in two Chaunax species. A. From holotype of C. mulleus sp. nov. B. From holotype of C. russatus sp. nov. Illustrated by M. Freeborn, Te Papa.

FIGURE 8. Distribution map of three Chaunax species in present study. Circle = Chaunax penicillatus. Triangle = C. reticulatu sp. nov. Square = C. russatus sp. nov. Open symbols are primary types. A symbol may represent more than one capture. Dashed line = limit of Exclusive Economic Zone. Prepared by C. Struthers, Te Papa. Dashed line = limit of Exclusive Economic Zone. Prepared by C. Struthers, Te Papa.

FIGURE 11. Chaunax russatus sp. nov., NMNZ P. 038059, holotype, 170 mm SL. A. Dorsal view. B. dorsal view of head. Photos: R. McPhee, Te Papa. C. NMNZ P. 014899, paratype, 145 mm SL, drawing of lateral view. Illustrated by E. McKay, Te Papa.

FIGURE 12. Micrographs of dermal squamation of Chaunax russatus sp. nov., BSKU 44629. A. Close – up view of lateral-line neuromast area. B. Dermal spinules. Taken by SEM at Biodiversity Research Center, Academia Sinica, Taipei.