Brachioteuthidae
Marek Lipinski and Richard E. YoungThis tree diagram shows the relationships between several groups of organisms.
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close boxIntroduction
Brachioteuthids are small to medium sized squids (ca. 15 cm ML). The mantle is muscular but generally rather thin. The tentacular clubs are unusual: The dactylus is normal (four sucker series) but the proximal part of the manus is greatly expanded and carries numerous small suckers on long stalks. Another unusual feature is the compact digestive gland that is located well posterior to the cephalic cartilage in the mantle cavity (note the spindle-shaped digestive gland in this photo).
Little is known about the biology of brachioteuthids although Roper and Vecchione (1996) describe an accumulation observed from a submersible near the ocean floor at a depth of about 800 m. An AVI format video clip of a squid from this aggregration is available here.
Diagnosis
An oegopsid ...
- with buccal connectives attaching to ventral borders of arms IV.
- with many series of irregular suckers on proximal manus; distal manus and dactylus with four regular series.
Characteristics
- Arms
- Arm suckers in two series.
- Buccal-crown connectives attach to ventral borders of arms IV.
- Tentacles
- Proximal region of manus of club greatly expanded with small suckers on long stalks in numerous irregular series.
- Dactylus of club with suckers in three or four series.
- Funnel
- Funnel-locking cartilage with straight groove.
- Funnel-locking cartilage with straight groove.
- Mantle
- Mantle muscular but thin.
- Mantle muscular but thin.
- Fins
- Fins short; anterior lobes free.
- Fins short; anterior lobes free.
- Photophores
- Single, large, ventral ocular photophore may or may not be present.
- Single, large, ventral ocular photophore may or may not be present.
- Viscera
- Compact digestive gland located well posterior to cephalic cartilage.
Nomenclature
A list of all nominal genera and species in the Brachioteuthidae can be found here. The list includes the current status and type species of all genera, and the current status, type repository and type locality of all species and all pertinent references.
Life history
Members of the family have characteristic paralarvae. The paralarvae have long necks containing a fluid-filled sac that extends as a reservoir into the body (Young, et al., 1985). Contraction of the reservoir can greatly increase the length of the neck, thereby extending the head from the mantle.
Figure. Ontogenetic stages of Brachioteuthis sp., Hawaiian waters. Top left - Egg. Top right - Hatchling, 2 mm ML, head retracted. Bottom left - Paralarva head and neck, 6 mm. Bottom right - Ventral view of the same hatchling, head retracted. Photographs by R. Young.
References
Roper, C. F. E. and M. Vecchione (1996). In-situ observations on Brachioteuthis: paired behavior, possibly mating. Am. Malac. Bull., 13(12):55-60.
Young, R. E., R. F. Harman and K. M. Mangold (1985). The eggs and larvae of Brachioteuthis sp. (Cephalopoda: Teuthoidea) from Hawaiian waters. Vie Milieu, 35: 203-209.
About This Page
Sea Fisheries Institute, Cape Town, South Africa
Richard E. Young
University of Hawaii, Honolulu, HI, USA
Correspondence regarding this page should be directed to Marek Lipinski at
Page copyright © 1996 and Richard E. Young
All Rights Reserved.
- Content changed 21 April 2008
Citing this page:
Lipinski, Marek and Young, Richard E. 2008. Brachioteuthidae http://tolweb.org/Brachioteuthidae/19409/2008.04.21 in The Tree of Life Web Project, http://tolweb.org/
. Version 21 April 2008 (under construction).