Chiroteuthis
Chiroteuthis is a genus of chiroteuthid squid, comprising two subgenera. The hectocotylus is absent from all members of the genus; instead, a penis extending from the mantle opening is utilised. The genus is characterised by enlarged, lidded photophores present at the end of the tentacular club. Arms IV are both the longest and thickest, their membranes acting as sheaths to the retractable tentacles. Species. The species listed above with an asterisk (*) is questionable and needs further study to determine if it is a valid species or a synonym.