Walvisteuthis rancureli (Okutani 1981)

Introduction

Walvisteuthis rancureli is a small squid; the maximum adult size recorded is a female of 150 mm ML (Bolstad, 2010).

• Description of the holotype (Onykia rancureli) can be found here.
  

Brief diagnosis:

A Walvisteuthis with ...

• robust, strongly recurved club hooks, with curved necks.
• longest club hooks ~15% club length.
• up to 5 marginal club suckers in combined dorsal and ventral series.
  

Characteristics

1. Arms
   1. Arm formula II> or = III=IV>I. Arms II-IV 86% of ML. Arms with 70-90 large suckers at >45 mm ML
      
2. Tentacles
   1. Tentacles robust; clubs ~38% ML (range: 33-48% ML. Carpus with 7-10 suckers. Manus with 24-27 hooks. Up to 5 marginal suckers present at 105 mm ML. Terminal pad with 8-11 suckers.
      
   2. Hooks robust, strongly curved in profile, with curved necks.Longest ventral hook (V5 or V6) ~3x length of dorsal counterpart and ~15% of club length at 105 mm ML or ~10% of club length at 35 mm ML. Ventral hook bases approximately symmetrical.
      
      

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      Figure. Oral view of the tentacular club of W. rancureli, female, 105 mm ML. Drawing from Bolstad (2010).
      

      

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      Figure. A large hook (V5) from the ventral hook series of the club of W. rancureli, female, 105 mm ML. Drawings - Slightly oblique profile view (left) and an oral view (right). Photograph - Scanning electron micrograph. All three images from Bolstad (2010).
      

3. Head
   1. Head length ~20% of ML (range 16-25%), width ~ 25% ML.
      
   2. Radula: Rachidian tricuspid; 1st lateral tooth bicuspid, ~60% of rachidian height; 2nd lateral tooth unicuspid, ~125% of rachidian height; marginal tooth ~200% of rachidian height.
      
      

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      Figure. Scanning electron micrograph of the radula of W. rancureli, male, 41 mm ML.

4. Fins
   1. Broadly ovate; length ~42%of ML (range: 32-49% ML); width ~93" of ML (range: 70-100% ML).
5. Photophores
   1. Photophores absent.
6. Gladius
   1. Gladius visible dorsally through integument. Rostrum ventrally through posterior ~3% of ML.

Comments

The above description W. rancureli is taken from Bolstad (2010) which contains more details than presented here.

References

Bolstad, K. 2010. Systematics of the Onychoteuthidae Gray, 1847 (Cephalopoda: Oegopsida). Zootaxa 2696: 1–186.