Cryptoteuthis brevibracchiata: Description continued

1. Arms
   
   1. Arm formula: I>II>III>IV; arm I length approximately twice mantle length and about 60% of total length.
   2. Web extends about 2/3 of arm length; web formula A>B>C>D>E.
   

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   Figure. Oral view of C. brevibracchiata, holotype. Scale bar - 40 mm. Drawing from Collins (2004). 

   3. Suckers in single series from mouth to arm tips.
      
   4. Sucker count 45-48.
   5. first cirri before third or fourth sucker; cirri extend to arm tips, longest on mid-arm.
      
      
2. Head
   1. Head slightly wider than mantle.
      
   2. Eyes lateral, moderate in size (32% head width).
   3. Optic lobes modereate in size, slightly larger than semi-circular central brain.
   4. White body cream colored.
   5. Beaks of typical cirrate form.
   

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   Figure. Side views of the beaks of C. brevibracchiata, holotype. Left - Lower beak. Right - Upper beak. Scale bar - 4 mm. Drawings from Collins (2004).

3. Funnel
   1. Funnel long (ca. 40% head width), flaccid.
      
      
4. Mantle
   1. Mantle 33% of total length; broadly rounded posteriorly.
   2. Mantle opening narrow, closely surrounds funnel.
      
      
5. Fins
   
   1. Posterior margins of fins with purple pigmentation; lateral margins rounded with slight point; anterior margins convex with distinct lobe.
   2. Fins with narrow, muscular base; muscular area extends 2/3 of fin length.
      
      
6. Shell
   1. Shell broad with simple U-shape and slightly flaring lateral wings.
   2. Inner and outer surfaces of basal portion of shell convex.
   3. Each lateral wing of shell terminates in a broad lobe with distinct, pointed extension (spike) on dorsal side.
      
   

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   Figure. Dorsal, ventral, lateral and anterior (bottom) views of the shell of C. brevibracchiata, holotype. Scale bar - 15 mm. Drawings from Collins (2004).
7. Viscera
   1. Olfactory organ rounded.
   2. Entire outer surface of digestive tract deeply pigmented.
   3. Oesophagus leads from buccal mass to stomach (a simple swelling of the oesophagus), then to caecum.
   4. Caecum with single turn and with two digestive gland ducts.
   5. Intestine straight, shorter than esophagus.
   6. Female genitalia simple, unpaired; oviducal gland in two parts, both cream colored.
      
   

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   Figure. Ventral view of the cut-open mantle cavity of C. brevibracchiata, holotype, showing the viscera. Scale bar - 15 mm. Drawing from Collins (2004).

8. Measurements 
   

   Sex	Immature female
   Total length	121 mm
   Mantle length	35 mm
   Head width	47 mm
   Fin span	92 mm
   Fin length	22 mm
   Fin width	15 mm
   Funnel length	19 mm
   Eye diameter	15 mm
   Arm I length	75 mm
   Maximum sucker diameter	1.8 mm
   Maximum cirri length	3.0mm
   Sucker location number of largest suckers	6-28
   Gill lamellae	7/7
   Gill diameter	6.0 mm

Comments

This description is from Collins, 2004. 

References

Collins, M. A. 2004. Cryptoteuthis brevibrancchiata: a new species and genus of cirrate octopod (Octopoda: Cirrata). Journal of Molluscan Studies. 70:263-267.