Teuthowenia maculata Leach 1817

Introduction

T. maculata is one of three similar species in the genus. The largest known specimen is an immature male of 143 mm ML. This is a small meso- to bathypelagic squid that is found in the tropical Eastern Atlantic. A detailed account of this species is given by N. Voss (1985).

Characteristics

1. Arms
   1. Arms I and II of males with 3-4 series of suckers on modified tips.
   2. Arms I and II of males with 25-27 normal suckers proximal to modified ends.
   3. Largest arm III suckers 3 times basal suckers in diameter (at least 3.2% of GL in diameter).
   

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   Figure. Oral views of arm tips of T. maculata. Top - Arm I tip. Bottom - Arm II tip. These are the extreme tips of the arms and occupy between just 3% and 8% of the arm length. Subadult male, 143 mm GL. Drawings from Voss, 1985, pp. 33, 34.

2. Mantle
   1. Single-point tubercle, poorly developed, at each funnel-mantle fusion.
      

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      Figure. Ventral view of the tubercle at the funnel-mantle fusion of T. maculata, hypotype, juvenile male, 123 mm GL. From Voss, 1985, pp. 33, 34.

3. Tentacles
   1. Largest club suckers with 22-26 teeth.
      

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      Figure. Oral view of the largest sucker from club manus of T. maculata, male, 143 mm GL.
      

Comments

The extent of the modifications to the arms of mature males is unknown. Additional details of the description of T. maculata can be found here.

Life history

The paralarval stage of T. maculata terminates at about 55 - 60 mm GL when the eyes become sessile. Generally a tubercule at the mantle-funnel fusion is not present in paralarvae. This species has chromatophores that are smaller, more numerous and more densely arranged than in the other species of the genus.

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Figure.  Dorsal views of growth stages of T. maculata. Left to right - 11 mm ML, 27 mm ML, 56 mm ML. Drawings from Voss, 1985, p. 22.

Distribution

Vertical distribution

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Data from opening-closing nets on the vertical distribution of this species have been reported at 11° N, 20° W (Lu and Clarke, 1975). Paralarvae up to about 20 mm ML were captured mostly in the upper 100 m during both the day and the night. By about 40 - 50 mm ML three of the four squid captured were taken between 500 - 700 m day and night; the fourth had apparently wandered upward at night and was taken at 300 - 400 m. The sparse data suggest that these squid undergo ontogenetic descent without diel vertical migration. Vertical distribution chart modified from Lu and Clarke, 1975.

Geographical distribution

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T. maculata is known only from the tropical Eastern Atlantic in oceanic waters whose depth exceeds 1000 m. At the northern end of its range, it appears to be confined to the oceanographically distinct region of the Mauritanian Upwelling (Voss, 1985). For a comparison with the distribution of the other two species, see "Teuthowenia." Geographical distribution chart modified from Voss, 1985.

References

Lu, C. C. and M. R. Clarke, 1975. Vertical Distribution of Cephalopods at 11° N 20° W in the North Atlantic. Journal of the Marine Biological Association of the United Kingdom, 55 (2): 369-389.

Voss, N. A. 1980. A generic revision of the Cranchiidae (Cephalopoda; Oegopsida). Bull. Mar. Sci. 30: 365-412.

Voss, N. A. 1985. Systematics, biology and biogeography of the cranchiid cephalopod genus Teuthowenia (Oegopsida). Bull. Mar. Sci. 36: 1-85.