Cephalopods · Sepiida · Sepiolidae

Hawaiian Bobtail

Euprymna scolopes

Data Deficient

There is not enough information to assess its risk of extinction. See full glossary

Euprymna scolopes, the Hawaiian bobtail squid, is a species of Sepiolida in the family Sepiolidae native to the central Pacific Ocean, occurring in shallow coastal waters off the Hawaiian Islands and the Midway Islands. The type specimen was collected off Hawaii and is held at the National Museum of Natural History, Washington, DC.

Size

up to 3 cm

Lifespan

1 years

Diet

Carnivore

Feeds mainly on other animals.

Activity

Nocturnal

Active mainly at night.

Social structure

Solitary

Lives and hunts alone, joining others only to breed.

Sighting difficulty

Unknown

OceanCarnivore Nocturnal Solitary Ocean Mollusc

1countries 3parks 3dive sites1same family

Fun facts

In a light organ in its mantle it houses a single bacterium, Vibrio fischeri, whose light it uses for counter-illumination: it matches the moonlight coming from above and erases its own silhouette from the view of predators below.
It is born without the bacterium. Each generation recruits it from seawater within hours, even though Vibrio fischeri makes up less than 0.1 % of the bacteria present. And if it is absent, no other bacterium will colonise the organ.
Every dawn it expels most of its bacteria and those left multiply again through the day, in a daily cycle.
It can regulate how much light its symbionts produce according to how much reaches it from the surface.
This partnership is one of the most important model systems in biology: bacterial quorum sensing was discovered with it, and it has been used to study how a microbiome establishes itself, how bacteria drive animal development and how pathogenicity evolves.

Life cycle & biology

Habitat & environment: Shallow sandy bottoms of the Hawaiian Islands, mostly seagrass meadows and sand flats; it buries itself by day and comes out to hunt at night

Sources consulted: https://es.wikipedia.org/wiki/Euprymna_scolopes