The Occurrence of Cryptosparas carunculatus from Cook Strait.
[Read before the Wellington Branch, April 23, 1941; received by the Editor, April 24, 1941; issued separately, September, 1941.]
On the morning of March 3rd, Mr. A. C. Kaberry, District Inspector of Fisheries, presented to the Dominion Museum a species of Angler Fish taken the previous day from the mouth of a Hake, Jordanidia solandri (Cuv. and Val.) from 100 fathoms in Cook Strait. This has been identified with Cryptosparas carunculatus Gunther, known from a single specimen 38 mm. long, from 345 fathoms, south of Yeddo, Japan.
Cryptosparas carunculatus Gunther. Plate 27.
General Characters: Body greatly compressed, skin clinging loosely over bones and wrinkled on sides; body outlines uneven and irregular; cleft of mouth subvertical; colour uniform blackish, covered with minute granules; eyes absent or rudimentary, not visible exteriorly.
Illicium: A modified anterior dorsal spine at the end of which is a bulb capable of emitting light; a structure found only in females * here placed at a point halfway between pectoral origin and angle of jaws; embedded in a deep socket; forwardly directed and cannot be easily raised to vertical; basal bone 4·3 in total length. Bulb has two terminal black ridges and deep V-shaped white band; no papilla or filament.
Caruncles: These outgrowths form a group in front of dorsal and consist of three pear-shaped processes, each with a pore above. The largest is in the centre and has in front a small papilla. The other two caruncles form a pair and are situated a little in advance of centre caruncle and lower down on sides. The one on the right is over half as large as the central; while, apparently, that of the left has “burst” and is small and flattened.
Fins: Dorsal and anal, each with 4 rays and caudal with 8, though some may be missing; pectorals about 15 rays, raised on fleshy protuberances. Anal base longer than in most described species. Longest caudal ray 34 mm.
Jaws: Maxillary bone above gives rise to a lateral expansion ending in 4 small tooth-like processes which cross upper part of pre-maxillary. Maxillary ends below in short anterior spine with 4 spiny rays behind it. A stout mandibular spine below at tip of jaw. When mouth is closed this spine and tooth-like maxillary structures (which somewhat resemble a small comb) are close together, and may form main offensive armature.
Teeth: In lower jaw teeth are arranged in two groups of 5 in single line outwards from angles. In front, teeth are long and
[Footnote] * Males are parasitic during part of their lives. They are very small and little known.
numerous, inwardly directed at an acute angle. In upper jaw all teeth are small, diminishing in number toward symphysis; 4 well-spaced teeth on head of vomer on each side.
Measurements: Total length 173 mm. or 139 + 34; depth at large caruncle 45 mm.; depth at illicium 58 mm.; lower jaw to branchial aperture 68 mm.
Discussion: The most outstanding feature of this Angler Fish is the absence of eyes; but this may be an adult feature. Regan and Trewavas, 1932, p. 26, give a synopsis of the species of Cryptosparas, species being separated mainly on length of basal bone of illicium in relation to length of fish. According to this key, our species agrees most nearly to the fish described on p. 98 as Cryptosparas normani; but that species is possessed of a terminal filament to the bulb of the illicium. Of C. normani Regan and Trewavas write: “We have some doubts as to the specific distinctness of this fish; but think it best to call attention to its peculiarities.”
Regan and Trewavas (1932, p. 40) give lateral views of the head, skeleton and pectoral arch of a Cryptosparas couseii, 200 mm. long and of another 25 mm. long. A comparison of these figures demonstrates very clearly that certain bones, slender in the smaller fish, are much thicker in the larger one. Regan and Trewavas point out that in the larger fish certain bones have much more extensive laminae and are quite different in form.
In view of this statement, we are unable to separate our species from the Japanese Ceratias carunculatus. Apparently, definite changes in the relationship of the long processes of the premaxillaries supporting expansions of maxillaries above takes place in most if not all species of Cryptosparas. In the larger fishes also the skull is relatively deeper, which accords with changes from young to adult in Cryptosparas couesii.
Norman (1930, p. 355) had the opportunity of making an examination of a live specimen of the related Cryptosparas normani. He noted that it was observed to beat the water with the pectoral fins, suggesting that this action was in some way connected with respiration. When the water was churned or the illicium stroked the luminous distal end emitted a greenish-blue light for half a minute or so. This phenomenon was noted three times.
Gunther, A., 1887. Report on the Deep-sea Fishes, Zoology, H.M.S. Challenger, vol. 22, p. 55, pl. XI, fig. D.
Goode and Bean, 1895. Ocean Ichthyology, p. 491, fig. 402.
Norman, 1930. Discovery Reports, vol. 2, p. 354, fig. 44.
Regan and Trewavas, 1932. Deep-sea Angler-fishes, Carlsberg Foundations Oceanographical Exped., 1928–30, p. 96.