Note

Introduction

Asperoteuthis nesisi is based on a single, trawl-captured, large female, 36 cm ML, lacking tentacles and captured in the South Atlantic near the Falkland Islands at 53°44'S, 58°46'W.

Brief diagnosis:

An Asperoteuthis ...

• with large (width more than half ML) fins.
• without enlarged suckers in the middle and distal portions of arms II and III.  
• with 12-14 pointed teeth on arm suckers.

Characteristics

1. Arms
   1. Arm formula: IV>II>I>III but arms nearly subequal.
   2. Arms IV slightly the thickest.
   3. Largest arm suckers at mid-region of arm length; largest on arms II, smallest on arms IV.
   4. Suckers with 12-14 sharp, triangular teeth distally on horny rings; proximal margin smooth.
      
      

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       Figure. Oral view of a arm III sucker of A. nesisi. Drawing (left) and photograph (right) from Arkhipkin and Laptikhovsky (2008).

      

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      Figure. Ventral view arms of the freshly caught A. nesisi. Photograph by A. Arkhipkin. 
      

2. Tentacles
   1. Tentacles missing; represented by short, slender stumps.
      
      
3. Head
   1. Radula with 7 rows of teeth; rhachidian with 3 cusps, first laterals with 2 cusps each.
      
      

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       Figure. Radula of A. nesisi. Drawing modified from Arkhipkin and Laptikhovsky (2008).
      

   2. Lower beak with well-developed lateral-wall fold, strongly angled wing fold extends nearly to tip of rostrum
      

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       Figure. Beaks from A. nesisi. Left - Side view of lower beak. Middle - Oblique view of lower beak. Right - Side view of upper beak. Photographs by A. Arkhipkin.

4. Funnel
   1. Funnel component of the funnel/mantle locking apparatus with asymmetrical antitragus, long, weakly developed tragus.
   2. Funnel valve present.
      
      

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       Figure. Frontal view of the funnel component of the funnel/mantle locking apparatus of A. nesisi. Drawing (left) and photograph (right) from Arkhipkin and Laptikhovsky (2008).

5. Mantle
   1. Mantle wall thin.
   2. Mantle covered with numerous, circular depressions containing more darkly pigmented skin.
   3. Muscle beneath depressions with vacuoles.
   4. Skin covered with tiny (0.1-0.2 mm high) tubercles.
      

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      © Alexander Arkhipkin

       

      

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      Figure. Ventral view of the anterior mantle of the freshly caught A. nesisi. Note the numerous circular depressions. Photograph by A. Arkhipkin. 
      

6. Fins
   
   1. Muscular, oval, slightly wider than long.
      
      
7. Photophores
   1. Large eyes each with single, long, longitudinal photophore on ventral surface.
      
      

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       Figure. Ventral-oblique view of the eye of A. nesisi showing the elongate ventral photophore. Drawing from Arkhipkin and Laptikhovsky (2008).

8. Measurements and Counts (from Arkhipkin and Laptikhovsky, 2008).

   Character	Measurements & counts	% of mantle length
   Mantle length	363
   Head length	88	24
   Head width	36	10
   Distance between eyes	18	5
   Maximum mantle width	100	28
   Fin length	220	61
   Fin width	246	68
   Arm I, length	312	86
   Arm II, length	335	92
   Arm III, length	303	84
   Arm IV, length	377	104
   Sucker diameter, arm I	3	0.8
   Sucker diameter, arm II	3.5	1.0
   Sucker diameter, arm III	4	1.1
   Sucker diameter, arm IV	2.5	0.7
   Eye diameter	27	7
   Eye photophore length	28	8
   No. suckers on proximal half of arm I	41
   No. suckers on proximal half of arm II	42
   No. suckers on proximal half of arm III	41
   No. suckers on proximal half of arm IV	48

Comments

The above description is based on the paper by Arkhipkin and Laptikhovsky (2008).

Salcedo-Vargas (1999) described Asperoteuthis lui (Cook Strait, New Zealand) based on the partially digested arms, one tentacle and eyes of a partial specimen taken from a fish stomach. This specimen had a distinctive tentacular club and enlarged suckers on arms II and III. The latter feature apparently separates it from A. nesisi but could represent sexual dimorphism. More specimens are needed to clarify the relationship between these two species.

For a comparison of all species of Asperoteuthis, go to the Asperoteuthis page.

Sequence data are available on Genbank via the following accession numbers for COI – EU421718, 16S rRNA –EU421719 and 12S rRNA – EU421720.

Nomenclature

This species appears to have been reported previously but not named. Clarke (1980) described it as ?Mastigoteuthis A. He had two specimens from the stomach of a sperm whale landed at the whaling station on South Georgia Island which lacked tentacles. A summary of Clarke's species can be found here. Nesis (1974) referred to two large paralarvae from the southwestern Atlantic as Chiroteuthis sp. n. and later (1982/87) suggested that his species was the same as Clarke's. A summary of Nesis's species can be found here. Arkhipkin and Laptikhovsky (2008) suggest that Clarke's species probably is Asperoteuthis nesisi.

?Mastigoteuthis A and A. nesisi have been placed in the synonomy of Asperoteuthis lui by Braid (2016).

References

Arkhipkin, A. I. and V. Laptikhovsky. 2008. Discovery of the fourth species of the enigmatic chiroteuthid squid Asperoteuthis (Cephalopoda: Oegopsida) and extension of the range of the genus to the South Atlantic. Journal of Molluscan Studies, 74: 203-207.

Braid, H.E. 2016. Resolving the taxonomic status of Asperoteuthis lui Salcedo-Vargas, 1999 (Cephalopoda, Chiroteuthidae) using integrative taxonomy. Mar. Biodiv. DOI 10.1007/s12526-016-0547-5

Nesis, K. N. 1974. Oceanic cephalopods of the southwestern Atlantic Ocean. Trudy Inst. Okean. Shirshova Akad. Nauk SSSR, 98: 51-75.

Nesis, K. N. 1982/87. Abridged key to the cephalopod mollusks of the world's ocean. 385,ii pp. Light and Food Industry Publishing House, Moscow. (In Russian.). Translated into English by B. S. Levitov, ed. by L. A. Burgess (1987), Cephalopods of the world. T. F. H. Publications, Neptune City, NJ, 351pp.