Some Additional New Zealand Cephalopods from Cook Strait
Family Chiroteuthidae — Genus Mastigoteuthis Verrill, 1881 — 1881. Bull. Mus. Comp. Zool., vol. 8, p. 100. — Type Species (monotypy): Mastigoteuthis agassizii Verrill. — Mastigoteuthis flammea Chun, 1908. Figs. 1, 2
Family Chiroteuthidae
Genus Mastigoteuthis Verrill, 1881
1881. Bull. Mus. Comp. Zool., vol. 8, p. 100.
Type Species (monotypy): Mastigoteuthis agassizii Verrill.
Mastigoteuthis flammea Chun, 1908. Figs. 1, 2.
1908. Mastigoteuthis flammea Chun, Wissensch. Ergebnisse Dcutsrhen Tiefsee-Exped., Bd. 18, Th. 1, p. 229.
Three specimens from the Cook Strait area match Chun's figures and description of Mastigoteuthis flammea in most details. They are considerably larger than either of Chun's specimens, the larger of which had a dorsal mantle length of 35 mm. The specimens taken by the Valdivia came from the Guinea Current and the northern limit of the Benguela Current in 3,500 and 2,000 metres respectively. The Cook Strait specimens were caught in nets fished from 825 to 1,100 metres (450 to 600 fathoms). Chun's figure (1910, Pl. 33, Fig. 4) shows the tentacular stumps as rather long. In the three New Zealand specimens the stumps of the tentacles are represented only as rounded bosses sunk in the pits from which the tentacles usually emerge. It would appear that the New Zealand form normally loses the tentacles, if they are ever actually functional. Obviously the function of these degenerate tentacles has been largely taken over by the fourth pair of sessile arms which arc greatly elongated. The rings from the suckers on the arms have longer, sharper hooks than those described by Chun for flammea, but this could possibly be a development correlated with increased size. The disposition of chromatophores and photophores is very much as figured for flammea by Chun. The preserved specimens when first seen by the writer were almost as brightly coloured as Chun's coloured plate of flammea but they have faded in the preservative.
Allan (1945, p. 335) recorded a small specimen (mantle length 13 mm) from off the east coast of Tasmania, tentatively under the name of grimaldi Joubin. Two species, M. cordiformis Chun and M. latipinna (Sasaki) have been recorded from Japanese waters and Berry has described M. famelica from Hawaii. This is the first record of the genus from New Zealand.
Localities: VUZ 86, 41° 47′ S, 175° 2′ E, south of Cape Palliser in c. 600 fathoms over c. 800 fathoms (figured specimen) ; VUZ 105, 41° 47′ S, 175° 1′ 30″ E, off Palliser Bay in 450–500 fathoms over c. 925 fathoms; VUZ 108, 41° 52′ 30″ S, 175° 6′ E, off Palliser Bay in c. 600 fathoms over c. 1,050 fathoms.
VUZ 105 mm | VUZ 86 mm | VUZ 108 mm | |
---|---|---|---|
Total length | 119 | 121 | 132 |
Dorsal mantle length | 45 | 44 | 48 |
Ventral mantle length | 42 | 42 | 46 |
Length of fins | 28 | 28 | 28 |
Width across fins | 30 | 30 | 31 |
Diameter of mantle at anterior margin | 10.5 | 10 | 9.5 |
Length of head | 10.5 | 12 | 10 |
Width across eyes | 10.5 | 13 | 9.5 |
Arms R.1 | 17 | 18 | 17 |
R.2 | 26 | 32 | 33 |
R.3 | 27 | 32 | 22 |
R.4 | 65 | 79 | 82 |
Length of funnel | 4 | 6 | 5 |
Diameter of right eye | — | 6.5 | 4.5 |