Chaunax mulleus, 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 : 95-98

Chaunax mulleus sp. nov.

New English Name: Redshoes frogmouth ( Figures 5 A–C, 6A, Table 1 )

Holotype. NMNZ P.039650 (146 mm), West Norfolk Ridge, New Zealand, 35º10.055'S, 169º 29.125'E, R/V Tangaroa , stn. NORFANZ TAN 0308/158, beam trawl, 867–869 m, 4 Jun. 2003.

Paratypes. 24 specimens, 112–161 mm SL. New Zealand: CSIRO H.6090–01, 150 mm, and CSIRO H.6090–02, 147 mm, collected with holotype. NMMB–P10460 (formerly NMNZ P.039659), 113 mm, collected with holotype. NMV A.25176–001, 138 mm SL and NMV A.25176–002, 147 mm, collected with holotype. NMV A 25177 –001, 2, 127– 140 mm and NMV A 25177 –002, 2, 107– 145 mm, W Norfolk Ridge, 35 º 10'S, 169 º29E, 871 m, 4 Jun. 2003. NMNZ P.035278, 119 mm, Hikurangi Trough, 39º25.8'S, 178º25'E, NZOI R 435, 985 m, Jun. 1990. NMNZ P.039649, 156 mm, NMNZ P.039658, 3, 131– 147 mm, and NMNZ P.039659, 114 mm, collected with holotype. NMNZ P.039669, 140 mm, and NMNZ P.039670, 112 mm, W Norfolk Ridge, 35º9.28'S, 169º28.805'E, R/V Tangaroa , stn. NORFANZ TAN 0308/159, 868– 872 m, ratcatcher trawl, 4 Jun. 2003. NMNZ P.044552, 127 mm, central Challenger Plateau, 40º7.605'S, 170º12.17993'E, R/V Tangaroa , stn. Ocean Survey 20/ 20 TAN 0707/106,803– 804 m, beam trawl, 5 Jun. 2007. NMNZ P.046017, 135 mm, NE Chatham Rise, 43º10.45'S, 174º18.3'W, F/V San Waitaki, stn. OBS 2428/027, 993–995 m, bottom trawl, 26 May 2007. Outside NZ EEZ. CSIRO H2942–01, 160 mm, 37 º 32'S, 169 º 07'E, Challenger Plateau, Tasman Sea, 980 m, 14 Apr. 1992. CSIRO H 3138–13, 127 mm, 35 º 26'S, 164 º 43'E, Lord Howe Rise, Tasman Sea, 929 m, 17 Jun. 1992. CSIRO H6041–01, 145 mm, 32 º 40'S, 162 º 33'E, Lord Howe Rise, Tasman Sea, 864 m, 25 May 2003. NMNZ P. 040942, 150 mm, central Louisville Ridge, 38º25'S, 168º09'W, F/V Sapun Gora, stn. OBS 1950/126, 1000 m, bottom trawl, 13 Jul. 2004. NMNZ P.044562, 161 mm, Challenger Plateau, NE Bellona Trough, 38º34.78'S, 167º8.995'E, R/V Tangaroa , stn. Ocean Survey 20/20 TAN 0707/056, 974 m, beam trawl, 31 May 2007.

Non-types. 7 specimens, 85–180 mm. NMNZ P. 011552, 85 mm, W Hikurangi Slope, SE of Cape Turnagain, 40º51.1'S, 176º57.5'E, F/V Kalinovo, stn. K 8101/145, 1058– 1100 m, bottom trawl, 18 Dec. 1981. NMNZ P. 012866, 180 mm, N Chatham Rise, 43º9.65'S, 174º37.7'W, F/V Kaltan, stn. KTN 8201/060, 885 m, 13 Aug. 1982. NMNZ P.017811, 3, 160– 170 mm, off Shoe and Slipper Islands, 37º6.2'S, 176º45.55'E, F/V Wanaka, stn. WNK 8502/056, 1052–1081 m, 11 Sep. 1985. NMNZ P.036062, 125 mm, Ritchie Banks, 40º4.8'S, 178º9.35'E, 720–972 m, F/V San Torshavn, stn. OBS 1172/061, bottom trawl, 15 Dec. 1998. NMV A 25139–007, 143 mm SL, Lord Howe Plateau, 32 º 41'48''S, 162 º 33'28''E, R/V Tangaroa , trawl, 855–874 m, 25 May 2003, coll. M. Gomon & NORFANZ team.

Diagnosis. A species unique for the genus in having a uniformly pinkish colour with deep red colour on under side of distal half of pectoral and pelvic fins and lower margin of caudal fin. It can be further distinguished from the congeners in having modally 1 spine on each side of lateral line neuromast complex; usually 12 pectoral-fin rays; a thin and tapering caudal peduncle; illicium relatively short and thick; esca whitish with some pink cirri when fresh; and greyish gill chamber and gill arches. Gill rakers: GRi =17–18 (3–4+14); GRii 14–15; GRiii 14–15; GRiv =12. Lateral-line neuromast counts: AB =11–13 (mainly 12); AC =8–9 (8); BB' =4–5 (4); BD =2–3; CD =6–8 (6–7); EF =3–6 (4); FG =4–5 (4); GH =11–15 (12–14); BI =32–40.

Description. Morphometric and meristic data are given in Table 1 . Head length 2.5 (2.3–2.6) in SL; head width 5.0 (4.9–5.6) in SL, 2.0 (2.0–2.3) in HL; pre-dorsal length 2.1 (2.0–2.2) in SL; pre-gill opening length 1.6 (1.5–1.7); pre-preopercular length 3.6 (3.2–3.7) in SL, 1.4 (1.4–1.5) in HL; upper jaw 4.8 (4.1 –5.0) in SL, 1.9 (1.9–2.1) in HL; illicial length 11.3 (8.7–11.3) in HL; illicial trough length 6.9 (5.5–7.4) in HL; eye diameter 4.7 (4.6–5.3) in HL; post-dorsal fin length 5.2 (4.5–5.7) in SL, 2.1 (1.7–2.2) in HL; post-anus length 3.2 (2.8–3.4) in SL, 1.3 (1.1–1.4) in HL; post-anal fin length 5.6 (5.2–6.5) in SL, 2.2 (2.1–2.8) in HL; caudal peduncle depth 4.5 (4.5–5.5) in HL; caudal fin length 3.3 (2.9–3.7) in SL, 1.3 (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 relatively long and slender, slightly compressed, tapering posterior. Eyes rounded, directed dorsolaterally, covered by dermal membrane broadly connected to adjoining skin, forming clear “window”.

Illicium short and stout; esca with large central tongue bearing many thin whitish and pinkish cirri; second dorsal-fin spine close to illicium, embedded under skin; third dorsal-fin spine situated at about mid-point of predorsal distance, embedded under skin. Illicial trough oval-shaped, slightly concave, relatively short and narrow, smaller than eye pupil, longer than wide ( Fig. 6 A).

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

Broad transparent membrane on first gill arch; first ceratobranchial broadly connected to opercular wall; gill filaments on second to fourth gill arches, two rows of gill filaments on second and third gill arches, single row of gill filaments on fourth gill arch; those on inner row of third arch and fourth gill arch about one-third length of those of other arches; inner surface of fourth gill arch completely connected to body. Single row of 17–18 rakers on 1st gill arch, 3–4 on upper limb and 14 on lower limb, 14–15 paired rakers on 2nd arch, 14–15 paired rakers on 3rd arch and single row of 12 rakers on 4th arch.

Interspaces of lateral-line neuromast complex slightly longer than its width; 1–3 (mainly 1) pairs of slender spines bridging neuromasts (cf. Fig. 1 B).

Skin thin, tips of pectoral- and pelvic-fin rays free. Dermal spinules long and slender, all simple, covering entire body, except eye window, outer half of pectoral fins, entire anal fin and membranes of others. Narrow band comprising 3–4 rows of spinules in front of illicial trough.

Teeth in both jaws slender, fang-like; 5–8 irregular rows in upper jaw, tooth length gradually increasing from outer to inner row, those in inner row longest; teeth in lower jaw in same arrangements. Teeth on vomer small, in two wide bands, each with about 3 rows, distinctly separated by a small medial space; teeth on palatine small, in elongate patch, close to outer end of vomerine patch.

Dorsal fin rays III, 12, first ray shortest, about half length of second; last two rays branched. Pectoral fin fanshaped, with 12–13 rays (mainly 12), 4th or 5th ray longest, those below 6th ray gradually shorter. Anal fin with 6–7 rays, first shortest, first and second simple, 3rd or 4th to the last branched. Caudal fin truncate, with 9 rays, second to seventh rays branched, other 3 simple, lower most ray shortest, close to adjacent one.

Colouration. Fresh ( Fig. 5 A–C): uniformly pinkish, except for deep-red colour on ventral surface of distal half of pectoral and pelvic fins and lower part of caudal fin. Cirri laterally on body bright white. Preserved: uniformly creamy white. Inner part of mouth cavity and gill chamber blackish, including gill arches.

Distribution. Endemic to the northern New Zealand region, extending from the southern Lord Howe Rise, central Challenger Plateau, West Norfolk Ridge, Bay of Plenty, eastern North Island and northern Chatham Rise, to the Louisville Ridge (Fig. 4) at 720–1100 m depth.

Etymology. From the Latin “ mulleus ” – a red shoe, in reference to the distinct deep–red ventral surface of outer half of the pectoral and pelvic fins and ventral surface of anal and caudal fins in fresh specimens.

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 5. Chaunax mulleus sp. nov., NMNZ P. 039650, holotype, 146 mm SL. A. Lateral view. B. Dorsal view. C. Ventral view. Photos: R. McPhee, Te Papa and K. Parkinson, AMS. D. Drawing of lateral view, illustrated by M. Freeborn, Te Papa.

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.