Abralia omiae Hidaka and Kubodera, 2000

Introduction

Abralia omiae is a member of the subgenus Pygmabralia. It is a small species with maximum size, apparently, less than 30 mm ML. Little is known of its general biology. It is very similar to the sympatric A. similis but, apparently, separable by the photophore pattern on the mantle and head and slight differences in the position of the lobes of the hectocotylus.

Brief diagnosis:

An Abralia (Pygmabralia) found in the Pacific Ocean and with ...

• large integumentary photophores on ventral mantle in three recognizable rows on either side of midventral "bare" strip.
• small photophores around mesial rows of large photophores together form two broad longitudinal bands.
• a monoserial row of photophores recognizable in the ventral midline of the head.
• proximal, bilobed ventral membrane of hectocotylus located close to dorsal edge of oral surface of arm.
  

Characteristics

1. Arms
   1. Arms with 6-13 hooks and distal suckers.
      
   2. Hectocotylus
      
      1. Right arm IV hectocotylized.
      2. 6-8  hooks proxmal to lobes, remainder of arm without armature.
      3. Ventral margin with large strongly bilobed proximal lobe followed by distinct, small, short lobe on dorsal margin but proximal lobes superficially appear to be along the dorsal margin.
      4. Ventral protective membrane forms low semilunar membrane at distal end of arm.
         
      

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      Figure. Oral view of the hectocotylized right arm IV of A. omiae. Drawing from Hidaka and Kubodera (2000, p. 421, Fig. 3D)
      

2. Tentacles
   1. Tentacular club with 1 or 2 hooks, ventral flap and dorsal keel.
      
      

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      Figure. Oral view of a tentacular club of A. omiae. Drawing from Hidaka and Kubodera (2000, p. 421, Fig. 3C)

3. Mantle
   1. Mantle with blunt, short tail, 7-10% of ML.
      
      
4. Photophores
   1. Occular photophores: 5 photophores with terminal and middle largest; monotypic structure.
      
      

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      Figure. Ventral view of the ocular photophores of A. omiae. Drawing from Hidaka and Kubodera (2000, p. 422, Fig. 4C).

   2. Integumental photophores of mantle
      
      1. Large photophores on mantle in six, ill defined, longitudinal rows but combined with small photophores form two broad longitudinal bands. About 400 small and 64 large photophores on ventral mantle.
      2. Midventral strip without photophores.
         
         
   3. Integumental photophores of funnel
      1. Two medial broad bands of photophores,  longitudinal row of 4 photophores on each side.
         
         

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         Figure. Ventral view of the funnel photophores of A. omiae. Drawing from Hidaka and Kubodera (2000, p. 422, Fig. 4B)

   4. Integumental photophores of head
      1. 20-24 large and about 150 small photophore in near-bilateral symmetry.
      2. Monoserial row recognizable in midline; medial band on either side; row of small photophores on ventral half of eyelid; semicirclar row of small photophores, broken by a gap in the center, between eyelid and medial band of photophores.
         
      

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      Figure. Ventrolateral view of the head photophores of A. omiae. Drawing from Hidaka and Kubodera (2000, p. 422, Fig. 4A).

   5. Integumental photophores of arms
      1. Arm III with 2 longitudinal rows of photophores; each with 3-4 small dark photophores and one large white photophore at arm base.
      2. Arm II with one, small photophore at dorsal arm base.
         
         
5. Epidermis
   1. Thick, fragile, and gelatinous.

Comments

The above description is taken from Hidata and Kubodera (2000).

Life History

Distribution

References

Hidaka, K. and T. Kubodera. 2000. Squids of the genus Abralia (Cephalopoda: Enoploteuthidae) from the western tropical Pacific with a description of Abralia omiae, a new species. Bulletin of Marine Science, 66(2):417-443.