Abraliopsis (Micrabralia)Richard E. Young
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IntroductionThe subgenus Micrabralia is presently a catch-basket for species that don't fit into the other two subgenera. The only unifying characters are (1) the presence of complex, integumental photophores in linear series on the head (in which it differs from A. (Abraliopsis) and A. (Boreabraliopsis) but shares with A. (Pfefferiteuthis), and (2) the absence of all the male modifications of both arms IV of A. (Pfefferiteuthis). A. (Micrabralia) gilchristi has strong similarities in character 1 with species of A. (Abraliopsis) and in character 2 with species of A. (Pfefferiteuthis).
Table. This table compares major features of the five species of the subgenus.
|A. gilchristi ||A. lineata ||Abraliopsis sp. NC1 ||Abraliopsis sp. E ||Abraliopsis sp. NC2 |
|Club keel ||large ||absent ||absent ||low, short||low, short |
|Carpal flap ||large ||absent ||absent ||low, short||absent|
|Size of large ventral:dorsal club hooks ||>3:1||<1.5:1 ||<1.5:1 ||2.5:1|| 3:1 |
|Arms I and/or II in males with tubercules ||Yes, mostly arm II ||Yes, mostly arm I ||Yes, only (?) arm I ||No||No |
|Distal third to half of arms IV bare ||No ||No (?) ||Yes ||No||No |
|Length of arms IV ||43-62% of ML || 50-60% of ML ||75-91 (x̅ =81.5, n=12) ||81% of ML|| 72-92 -(x̅ =87.1, n=7) |
|No. hooks, arms IV ||23-28 ||10-13|| 8-14 (x̅=10.6, n=14) ||18,24||20-29 (x̅ =23.4, n=10) |
|Spermatangia receptacles ||? ||Dorsal collar, Stellate pouch, Nuchal cartilage ||Dorsal collar , Stellate pouch ||?||Dorsal collar , Stellate pouch |
|No. of ventral head photophore series ||4 ||3||3||3||3|
|Photophores in Medial Head Sector ||None to few || Many throughout ||Many throughout||None||Many throughout|
About This Page
University of Hawaii, Honolulu, HI, USA
Correspondence regarding this page should be directed to Richard E. Young at
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Page: Tree of Life Abraliopsis (Micrabralia). Authored by Richard E. Young. The TEXT of this page is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0. Note that images and other media featured on this page are each governed by their own license, and they may or may not be available for reuse. Click on an image or a media link to access the media data window, which provides the relevant licensing information. For the general terms and conditions of ToL material reuse and redistribution, please see the Tree of Life Copyright Policies.
- First online 03 November 2013
- Content changed 29 August 2016
Citing this page:
Young, Richard E. 2016. Abraliopsis (Micrabralia). Version 29 August 2016 (under construction). http://tolweb.org/Abraliopsis_%28Micrabralia%29/149533/2016.08.29 in The Tree of Life Web Project, http://tolweb.org/