Helicocranchia pfefferi Massy 1907

Introduction

The large number of undescribed species in the genus makes identification of any specimens difficult. Since the type locality of H. pefferi is in the North Atlantic, the North Pacific form of H. pfefferi described here may be one of these undescribed species.

Characteristics

1. Arms
   1. Distal half of arms I and II in males with numerous sucker series (4 series in arms I, 8-9 in arms II.
      
   2. Suckers in middle of arms III not enlarged in females.
      
      

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      Figure. Views of H. pfefferi. Left - Oral view of the left dorsal arms showing male modifications to arm tips. Drawings from Young (1972). Right - Insitu ROV photographs of a male at 971 m depth, Gulf of California. ©2013 MBARI.
      

2. Head
   
   1. Beaks: Descriptions can be found here: Lower beak; upper beak.
      
      
3. Mantle 
   1. Papillae absent.
      
      
4. Pigmentation
   1. Orange/brown chromatophores form bands of sides of mantle.
      
      

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      Figure. H. pfefferi, small, northeastern Atlantic. Dorsal view of the pigmentation pattern. See also the title photograph above. Photographed by M. Vecchione in a shipboard aquarium.

Comments

Life History

Paralarvae are easily recognized as belonging to Helicocranchia by their shape and chromatophore patterns. In Hawaiian waters, however, there appears to be two different species in the genus. Two features, however, distinguish this paralarva from its less common congener (H. beebei?): The color pattern has more distinct bars and the eyes lack a long optic stalk (i.e., the optic lobe is adjacent to the central brain).

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Figure. Ventral and dorsal views of paralarvae of H. pfefferi, Hawaiian waters. Left - 3.4 mm ML . Right - 4.4 mm ML. Arrows point to chromatophores that are part of prominent lateral bars. Ventral-head chromatophores hidden by the funnel are represented by dashed lines. The scale bar is 1 mm. Drawings by R. Young.

Distribution

Vertical distribution

Off California, captures made with open nets indicated an ontogenetic descent and no diel vertical migration. The majority of specimens over 40 mm ML were taken at depths of 400-600 m.

Geographical distribution

The type locality is the temperate North Atlantic, near Ireland (51°54'N, 11°57'W). Due to the large number of undescribed species in this genus, the distribution of H. pfefferi is uncertain.

Other Names for Helicocranchia pfefferi Massy 1907

• Banded piglet squid

References

Young, R. E. 1972. The systematics and areal distribution of pelagic cephalopods from the seas off Southern California. Smithson. Contr. Zool., 97: 1-159.

Young, R. E. 1978. Vertical distribution and photosensitive vesicles of pelagic cephalopods from Hawaiian waters. Fish. Bull., 76: 583-615.