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Alloteuthis Wulker, 1920

Michael Vecchione
Alloteuthis contains three species.
taxon links [down<--]Loliginidae Interpreting the tree
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Type species. -- Loligo media Linnè, 1758 by original designation of Naef in an unpublished manuscript cited by Wulker [see Vecchione et al. (1998)].
Containing group: Loliginidae

Introduction

Small loliginids of the eastern Atlantic.

Diagnosis

A loliginid ...

Characteristics

  1. Arms
    1. Hectocotylus:
      1. Ventral crest absent.
      2. Proximal suckers unmodified.
      3. Proximal region with 10 - 12 (usually 11) normal suckers in ventral series followed distally by papillae.
       image info

      Figure. Oral view of the hectocotylus of Alloteuthis media, Gulf of Tunis, preserved. Photograph by R. Young.

  2. Tentacles
    1. a Tentacular clubs expanded, suckers in four series; two medial manal series with larger suckers.

  3. Head
    1. Buccal supports without suckers.

  4. Mantle
    1. Mantle long, relatively narrow; posterior end drawn out into narrow, pointed tail, up to 6 cm in adults.
     image info

    Figure. Ventral view of A. subulata showing dimorphism in the relative sizes and shapes of mature males. Top - Small male which we presume to be a sneaker male (sneakers are known in L. reynauldii - Hanlon, et al., 2002). Bottom - Large male with elongate tail. Females are approximately the same size and shape as the small male. Drawings from Naef (1921-3).

  5. Fins
    1. Fins reach posterior tip of mantle.
    2. Fins heart-shaped, lateral angles rounded, posterior borders concave, extending posteriorly along tail.

  6. Photophores
    1. Photophores absent.

  7. Viscera
    1. Eggs small.
    2. Spermatophore with small cement gland.

Comments:

Alloteuthis is morphologically very similar to Loligo and was considered by Vecchione et al. (1998) to be a subgenus.  However, molecular analyses by Anderson (2000) indicate that Alloteuthis should be a separate genus. This supports earlier inferences by Naef (1921-23) and Alexeyev (1989) that the presence of a gladial conus in Alloteuthis should be considered a generic character. The conus in Alloteuthis would clearly separate the genera but it can be very difficult to find and in some Alloteuthis specimens may be reduced until it is essentially absent. The posterior tip of the mantle in Alloteuthis is elongate into a tail-like structure that tends to be more pointed than in Loligo.  This is particularly true for males but identification of this character state can be subjective in females.

Distribution

Eastern Atlantic Ocean from about 55°-60°N to 20°S.

References

Anderson, F.E. 2000. Phylogeny and Historical Biogeography of the Loliginid Squids (Mollusca: Cephalopoda) Based on Mitochondrial DNA Sequence Data. Molecular Phylogenetics and Evolution 15: 191-214.

Alexeyev, D.O. 1989. Advantages and limitations of using the gladius in diagnosis of species and genera of the family Loliginidae (Cephalopoda). Zoologichesky Zhurnal, 68(6):36-42.

Naef, A. 1921-1923. Die Cephalopoden. Fauna e Flora del Golfo di Napoli, Monographie 35, Vol I, Parts I and II, Systematik, pp 1-863.

Vecchione, M., T. F. Brakoniecki, Y. Natsukari and R. T. Hanlon. 1998. A provisional generic classification of the family Loliginidae. Smithson. Contr. Zool., 586.

Vecchione, M., E. Shea, S. Bussarawit, F. Anderson, D. Alexeyev, C.-C. Lu, T. Okutani, M. Roeleveld, C. Chotiyaputta, C. Roper, E. Jorgensen and N. Sukramongkol. 2005. Systematics of Indo-West Pacific loliginids. Phuket Mar. Biol. Cent. Res. Bull. 66: 23-26.

Title Illustrations
Scientific Name Alloteuthis media
Location Gulf of Tunis, Mediterranear Sea
Specimen Condition Preserved
Sex Female
View Ventral
Size 62 mm ML
Copyright © Richard E. Young
About This Page



National Marine Fisheries Service
Systematics Laboratory
National Museum of Natural History
Washington, D. C. 20560
USA

Citing this page:

Vecchione, Michael. 2006. Alloteuthis Wulker, 1920. Version 25 January 2006 (under construction). http://tolweb.org/Alloteuthis/23876/2006.01.25 in The Tree of Life Web Project, http://tolweb.org/

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