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Rossiinae Appellof, 1898

taxon links [down<--]Sepiolidae [up-->]Austrorossia [up-->]Neorossia [up-->]Rossia [up-->]Semirossia Interpreting the tree
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Containing group: Sepiolidae

Introduction

Members of the Rossinae are among the larger sepiolids reaching up to 10 cm ML (Reid, 1991). They are benthic and mostly occupy the outer portions of the continental shelves and upper regions of the slope. The subfamily nearly has a world wide distribution (see below) along parts of major land masses but is not know from Antarctic waters.

Diagnosis

A sepiolid ...

Characteristics

  1. Arms
    1. Interbrachial web weakly developed between arms I-III.
    2. Non-hectocotylized arm suckers in 2 series in most species but 4 series in at least two species.
    3. One or both dorsal arms of male hectocotylized; often with suckers in two or four series among other modifications.
  2. Tentacles
    1. Tentacular clubs usually expanded.
    2. Keel along full length of club.
       image info

      Figure. Oral view of the tentacular club of Rossia pacifica, preserved. Photograph by R. Young.

  3. Mantle
    1. Mantle free from head in nuchal region; nuchal cartilage present.
       image info

      Figure. Dorsal view of the mantle and head of Rossia macrosoma with anterior portion of mantle folded back to reveal the nuchal cartilage (blue) and anterior end of the gladius (red). Drawing modified from Naef (1921-23).

  4. Gladius
    1. Gladius fully-developed but thin posteriorly.
  5. Viscera
    1. Bursa copulatrix absent.
  6. Photophores
    1. Photohores, when present, with with small, separate oval lenses.

Comments

The following table compares the four genera.

  Arms II, III with greatly enlarged suckers Clubs expanded Club sucker series Photophores present on ink sac Functional Ink sac Anal flaps
Austrorossia* No No 25-50 No Yes Rudiment
Neorossia No Yes 6-7 No No Rudiment
Rossia No Yes 6-12 No Yes Strong
Semirossia Yes Yes 5-8 Yes Yes Strong

Austrorossia is often considered a subgenus of Rossia (Voss, 1956; Reid, 1991). We follow the classification of Nesis (1982/87).

Distribution

 image info

Figure. Distribution map of the Rossiinae (white lines). Distributions are approximate. Modified from Young, et al. (1998).

References

Reid, A. 1991. Taxonomic Review of the Australian Rossiinae (Cephalopoda: Sepiolidae), with a Description of a New Species, Neorossia leptodons, and Redescription of N. caroli (Joubin, 1902) . Bulletin of Marine Science, 49(3)(1991):748-831.

Young, R. E., M. Vecchione and D. Donovan. 1998. The evolution of coleoid cephalopods and their present biodiversity and ecology. South African Jour. Mar. Sci., 20: 393-420.

Voss, G.L. 1956. A Review of the Cephalopods of the Gulf of Mexico. Bulletin of Marine Science of the Gulf and Caribbean, 6(2):85-178.

Title Illustrations
Scientific Name Rossia sp.
Location Off N.E. United States
View Dorsolateral
Copyright © 2004
Scientific Name Rossia glaucopis
Reference Verrill, A.E. 1880-1881.? The cephalopods of the north-eastern coast of America. Part II. The smaller cephalopods, including the "squids" and the octopi, with other allied forms.? Transactions of the Connecticut Academy of Sciences, 5(6):259-446, 33 plates.
View Dorsal
Size 23 mm ML
Scientific Name Rossia glaucopis
Reference Verrill, A.E. 1880-1881.? The cephalopods of the north-eastern coast of America. Part II. The smaller cephalopods, including the "squids" and the octopi, with other allied forms.? Transactions of the Connecticut Academy of Sciences, 5(6):259-446, 33 plates.
View Ventral
Size 31 mm ML
About This Page
Citing this page:

Tree of Life Web Project. 2004. Rossiinae Appellof, 1898. Version 30 August 2004 (under construction). http://tolweb.org/Rossiinae/20023/2004.08.30 in The Tree of Life Web Project, http://tolweb.org/

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