Characteristics
- Arms
- Hooks in medial two armature series on arms I-III.
- Tentacles
- Tentacles present in subadults.
- Tentacular club without hooks.
- Suckers of tentacular club in numerous irregular series; suckers about equal in size.
- Proximal locking-apparatus of club with suckers and knobs medial to 2-3 small ridges and grooves.
- Head
- Beaks. Descriptions can be found here: Lower beak; upper beak. See also this site.
- Radula with teeth in 5 series.
- Mantle
- Mantle tissue flabby.
- Fins
- Fins sagittate, drawn out posteriorly into a short tail.
- Photophores
- Photophores absent.


