Enoploteuthis magnoceani Nesis 1982

Introduction

Enoploteuthis magnoceani, has never been fully described and we know less about it than most species of the genus.

Characteristics

1. Arms: Hectocotylus
   1. Hectocotylus with a large truncate membranous flap on the ventral edge.
   2. Modified portion with armature.
      

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      Figure. Oral-dorsal view of the hectocotylus of E. magnoceani, male, from Northwest Pacific. Drawing from Tsuchiya (2000).

2. Tentacle
   1. Tentacle short, narrow.
   2. Carpal cluster elongate.
   3. Two rows of subequal-sized hooks on manus.
   4. Two rows of suckers on dactylus.
      

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      Figure. Oral view of the tentacle club of E. magnoceani, from Northwest Pacific. Drawing from Tsuchiya (2000).

3. Head
   
   1. Beaks: Descriptions can be found here: Lower beak; upper beak.
      
      
4. Integumental Photophores
   1. Ventral mantle with five longitudinal but weakly oblique stripes of integumental organs; median stripe actually two, closely adjacent, longitudinal rows that converge anteriorly then join and terminate prior to reaching mantle margin. ventralmost pair of stripes is obscure and fused to lateral rows; narrow photophore-less strip at the midline.
      
      

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      Figure. Ventral views of mantle photophores of E. magnoceani, immature females. Top - 45 mm ML. Bottom - 70 mm ML. Arrows point to the anterior end of the median stripes. Photographs of preserved squid by R. Young.
      

   2. Ventral head with six longitudinal stripes of integumental organs (does not include eyelid photophores). Lateral-most stripe broken at window in integument. Photophores absent between the latter and eyelid photophores.
      
      

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      Figure. Head photophores of E. magnoceani. Left - Ventral view, 70 mm ML. Right- Ventrolateral view, 45 mm ML. Photographs of preserved squid by R. Young.

   3. Ventral side of arm III with a row of organs along almost entire arm.

Nomenclaure

Nesis (1982/87) considered the Pacific form of E. leptura to be a separate subspecies E. leptura magnoceani due to the photophore arrangement of anterior ventral mantle. Although the description of E. magnoceani is incomplete, the evidence is adequate to consider it as a valid species.

Distribution

Geographical distribution

Tropical western and central Pacific Ocean and Australo-Asiatic seas (Nesis, 1982/87) also in the western North Pacific.

References

Nesis, K. N. 1982. Abridged key to the cephalopod mollusks of the world's ocean. 385+ii pp. Light and Food Industry Publishing House, Moscow. (In Russian.). Translated into English by B. S. Levitov, ed. by L. A. Burgess (1987), Cephalopods of the world. T. F. H. Publications, Neptune City, NJ, 351pp.

Roper, C.F.E., 1966. A study of the genus Enoloteuthis (Cephalopoda: Oegopsida) in the Atlantic Ocean with a description of the type species, E. leptura (Leach, 1817). Dana Report, 66:1-46.

Tsuchiya, K. 2000. Illustrated book of the Enoploteuthidae. In: Okutani T., ed. True face of Watasenia scintillans. Tokai University Press, Tokyo, p 196–269. (in Japanese)