Memoirs of the Museum of Victoria 48(1): 25-26 (1987)
ISSN 0814-1827
NEW AUSTRALIAN FISHES. PART 7.
A NEW SPECIES OF CHOERODON (LABRIDAE).
By M. F. Gomon' and G. R. Allen 2
'Department of Ichthyology, Museum of Victoria, 328 Swanston Street, Melbourne,
Victoria 3000, Australia
department of Ichthyology, Western Australian Museum, Francis Street, Perth,
Western Australia, 6000, Australia
Abstract
Gomon, M.F. and Alalen, G.R., 1987. New Australian fishes. Part 7. A new species of Choerodon
Labridae). Mem. Mus. Vict. 48: 25-26.
A description of a new tuskfish Choerodon cauteroma, restricted to north-western Australia,
is presented. It is distinctive in having a relatively deep body and prominent black mark on the
upper portion of the side below the seventh dorsal spine.
Introduction
Recent field studies and revisionary treatments
of Australian taxa have differentiated a number
of undescribed labrid fishes. Separate concurrent
studies by the two authors identified the species
of Choerodon treated below as new. Methods for
this description follow Gomon (1974).
Labridae
Choerodon
Choerodon Bleeker, 1847: 10.
Type species. Labrus macrodontus Lacepede ( =
C. anchorago Bloch) by monotypy.
Discussion. Choerodon is a large, morphologi-
cally diverse genus with general body configura-
tions varying from slender and streamlined to
quite deep-bodied. An unpublished study of this
genus and related genera undertaken by the first
author has revealed the presence of two un-
described species of Choerodon that appear to
be restricted to northern Australian waters. Both
have been cited in recent works treating, at least
in part, Australia's North-west Shelf. A descrip-
tion of one of these species is presented below.
Choerodon cauteroma sp. nov.
Choerodon sp. 1 Gloerfelt-Tarp & Kailola, 1983: 235, colour
figure on opposing page.
Choerodon sp. 1 Sainsbury et al., 1984: 260, colour figure
on opposing page.
Choerodon sp. Allen, 1985: 2406, figs. 330, 331.
Material examined. Holotvpe: Western Australia, Exmouth
Gulf, collected by J.B. Hutchins, 6 Dec 1975, WAM P25508-
042 (terminal phase adult, 203 mm SL).
Paratypes: Western Australia, Dampier Archipelago
(20°28.5'S, 116°32E), J.B. Hutchins, 24 Nov 1974, WAM
P24259 (initial phase, 195 mm SL). North-west Shelf (20°46-
48'S, 115 o 59'-116°00'E), 19-22 m, FRV "Soela", collected by
CSIRO, 1 Dec 1979, CSIRO H659-01 (initial phase, 176 mm
SL). Exmouth Gulf, M. Lane, Oct 1974, WAM P25095-038
(initial phase, 6 specs., 98.3-144 mm SL). Off Exmouth Yacht
Club, 4-5 m, spear, OR. Allen, 1 Jul 1975, WAM P25372-
001 (initial phase, 3 specs., 90.2-104 mm SL). Shark Bay. R.J.
McKay, 8 Jul 1962, AMS 1.26373-001 (initial phase and ter-
minal phase, 2 specs., 130-205 mm SL), NMV A3819 (initial
phase and terminal phase, 4 specs., 114-208 mm SL), USNM
280629 (initial phase and terminal phase, 2 specs., 115-158
mm SL). Same area, Poole Bros., May 1964, BPBM 30944
(initial phase, 110 mm SL).
Other material: Western Australia, Elphicks Knob (20°28'
S, 116°37' E), collected by R.J. McKay, 26 Nov. 1971, WAMP
23092-4 (3 juveniles, 20.5-40.2 mm SL).
Description. Dorsal-fin rays XIII, 7; anal-fin rays
III, 10; pectoral-fin rays ii, 15-16 (ii, 15 in holo-
type; ii, 15 in 37 of 40 fins counted); lateral-line
scales 27 + 2; predorsal scales 5-8 (5 in holotype;
modally 6); scales above lateral line 4-4 1/2 (4 in
holotype). Body and head deep, body depth 36.3-
43.0 (37.3 in holotype). Eye large. Predorsal
scales reaching forward to above hind edge of
preopercle. Cheek scales reaching forward to
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