by Mike Vecchione, NOAA/National Marine Fisheries Service National Systematics Lab, National Museum of Natural History
June 26, 2018
Doesn't look much like a squid does it?
Although this animal looks sort-of like an octopus, when you listen to the audio you hear the onboard scientists refer to it as a "dumpling squid." That is a local term sometimes used for species of the cephalopod order Sepiolida. They have fins and when they are sitting on or buried in the bottom, their fins are wrapped so tightly around the body that they are difficult to distinguish.
Because of their rounded bodies, sepiolids are generally known as "bobtail squids." Although called squids, bobtails have long been considered to be modified cuttlefishes that have lost the internal shell (cuttlebone). However, recent evidence from DNA sequencing indicates that they are not closely related to either squids or cuttlefishes, although they are in the broad group of 10-armed cephalopods. Bobtails have a large bacterial light organ aimed downward in the body and because of this one shallow-water "dumpling" has become very well known as a model for the study of inter-relationships between an animal and the microbes that live inside it.
This bobtail is a benthic (bottom-living) species of the subfamily Rossiinae (see http://tolweb.org/Rossiinae/20023 ). There are several genera in this area but they are difficult to identify confidently without dissecting them under a microscope.