Sepiolina nipponensisRichard E. Young and Michael Vecchione
Sepiolina nipponensis is a peculiar sepiolid whose characteristics place it between the Heteroteuthinae and the Sepiolinae. The tentacular club with a normal keel is similar to that of the Sepiolinae while the silvery sides, ventral shield and large visceral photophore are similar to those of the Heteroteuthinae. A better understanding of the features and habits of this species should greatly aid our understanding of the evolution within the family.
A heteroteuthin ...
- with mantle narrowly fused to head dorsally.
- without tentacular organ on tentacles.
- Arms I of males with glandular structures along dorsal and ventral margins over most of arm length.
- Arms II and III, in males, with greatly enlarged suckers; suckers enlarged to a lesser extent on arms IV.
- Arms of females without obvious modifications.
- Keel extends full length of tentacular club (unlike other heterothins, a tentacular organ is lacking) however, the base of the keel is modified with a permanent fold.
- Ocular pore present unlike most (all?) other heteroteuthins.
- Funnel locking-apparatus with a deep, elongate anterior pit.
- Mantle fused to head dorsally; fusion narrower than head width.
- Ventral mantle shield extends almost entire length of mantle (see title photograph).
- Lateral mantle with broad, silver band.
Click on an image to view larger version & data in a new window
Figure. Left - Side (top) and ventral views of preserved S. nipponensis, 23 mm ML, female (top), 15 mm ML, male (bottom), Japanese waters, showing the extent of the ventral shield. Photograph by R. Young. Right - Ventral view with funnel cut open and mantle removed to show the visceral photophore (colored blue for emphasis). Drawing modified from Sasaki (1929).
- Fins do not reach anterior or posterior margins of mantle.
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.
Sasaki, M. 1929. A Monograph of the Dibranchiate Cephalopods of the Japanese and Adjacent Waters. Journal of the College of Agriculture, Hokkaido Imperial University, 20(supplement):357 pages.
Richard E. Young
University of Hawaii, Honolulu, HI, USA
Page copyright © 2004 Richard E. Young and
- First online 01 September 2004
- Content changed 10 December 2006
Citing this page:
Young, Richard E. and Vecchione, Michael. 2006. Sepiolina http://tolweb.org/Sepiolina_nipponensis/20034/2006.12.10 in The Tree of Life Web Project, http://tolweb.org/. Sepiolina nipponensis . Version 10 December 2006 (under construction).