Cirroteuthidae Keferstein 1866

Introduction

Species in the family are entirely pelagic and have a very fragile, gelatinous structure and eyes that vary from large to small to degenerate. They are usually found in association with the ocean floor (benthopelagic) at great depths. Some have, however, been caught far above the bottom and one specimen was dip-netted through an ice hole in the Arctic.

Brief diagnosis:

A cirrate ...

• with long cirri and secondary webs.
• with saddle-shaped shell.
• with anterior mantle attached dorsally to head. 

Characteristics

1. Shape and consistency
   1. Anterior-posteriorly elongation pronounced; body extends well posterior to shell.
      
      
2. Web
   1. Primary and secondary webs present.
   2. Web nodules present or absent.
      

      Click on an image to view larger version & data in a new window
      

      Figure. Oral view of left arm III of Cirroteuthis muelleri. Drawing modified from Voss and Pearcy, 1990.

      

      Click on an image to view larger version & data in a new window

      

      Figure. Ventral and aboral views of Cirroteuthis muelleri taken by an ROV in the Canadian Basin of the Arctic Ocean. The short, slender arm tips extend beyond the web. The web nodules are seen where the web intersects the arm from the ventral side. Frame grabs from a video taken during a NOAA/OE Census of Marine Life cruise; provided by Kevin Raskoff.

3. Cirri
   1. Very long: Longest more than 8 times largest sucker diameter.
      
      
4. Suckers
   1. Central portion of each arm with small, flattened suckers, nearly lacking acetabulum (i.e., aperatures may be virtually absent), on stalks that are either slender or swollen and fluid-filled.
      
      
5. Gills
   1. Gills with sepioid form.
      
      
6. Digestive system
   1. Digestive tract arranged in simple U-shape; intestine short, without lateral bends
   2. Posterior salivary glands present on buccal mass.
   3. Radula present or absent.
   4. Digestive gland unilobular.
      
      
7. Reproductive system.
   1. Male accessory gland complex compacted into a single mass.
      
      
8. Optic lobe
   1. Spherical.
   2. Single optic nerve bundle penetrates white body.
      
      
9. Shell
   1. Saddle-shaped: Broad saddle with two lobe-like, deeply escavated flared wings, pronounced shoulders.
      

      Click on an image to view larger version & data in a new window

      

      Left, middle - Ventral and dorsal views of the shell of Cirroteuthis muelleri. Drawings from Voss and Pearcy (1990). Right - Dorsal view of the shell of Cirrothauma murrayi. Drawing from Aldred et al. (1983).

References

Aldred, R. G., M. Nixon and J. Z. Young. 1983. Cirrothauma murrayi Chun, a finned octopod. Phil. Trans. Roy. Soc. Lond. 301: 1-54.

Voss, G. L. and W. G. Pearcy. 1990. Deep-water octopods (Mollusca: Cephalopoda) of the Northeastern Pacific. Proc. Calif. Acad. Sci., 47: 47-94.