Rossiinae
Richard E. Young
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close boxIntroduction
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.
Brief diagnosis:
A sepiolid ...
- with dorsal mantle free from head.
- without ventral mantle shield.
Characteristics
- Arms
- Interbrachial web weakly developed between arms I-III.
- Non-hectocotylized arm suckers in 2 series in most species but 4 series in at least two species.
- One or both dorsal arms of male hectocotylized; often with suckers in two or four series among other modifications.
- Tentacles
- Tentacular clubs usually expanded.
- Keel along full length of club. Click on an image to view larger version & data in a new window
Figure. Oral view of the tentacular club of Rossia pacifica, preserved. Photograph by R. Young.
- Mantle
- Mantle free from head in nuchal region; nuchal cartilage present. Click on an image to view larger version & data in a new window
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).
- Gladius
- Gladius fully-developed but thin posteriorly.
- Viscera
- Bursa copulatrix absent.
- Photophores
- 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
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 |
| Image Use |
 This media file is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0.
|
| 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
Richard E. Young
University of Hawaii, Honolulu, HI, USA
Correspondence regarding this page should be directed to Richard E. Young at
Page copyright © 2004 Richard E. Young
Page: Tree of Life
Rossiinae .
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Richard E. Young.
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- First online 30 August 2004
Citing this page:
Young, Richard E. 2004. Rossiinae . Version 30 August 2004 (under construction). http://tolweb.org/Rossiinae/20023/2004.08.30 in The Tree of Life Web Project, http://tolweb.org/
