cephalopods text index | photo index
Phylum Mollusca > Class Cephalopoda > squids and cuttlefishes
Bobtail squids
Suborder Sepiolida
updated Oct 2016
Where seen? These rotund little squids are sometimes seen on our Northern shores on sandy areas among seagrass meadows.

What are bobtail and bottletail squids? They are molluscs (Phylum Mollusca) like snails, slugs and clams; and cephalopods (Class Cephalopoda) which include octopuses. They belong to the Suborder Sepiolida. Bobtail squids belong to the Family Sepiolidae while Bottletail squids belong to the Family Sepiadariidae.

Features: 2-4cm. These squids are generally rather spherical with a pair of rounded fins that make them look a little like an aquatic version of Dumbo the Flying Elephant! These squids can only be positively identified by examining the arm and suckers of the males. Females are difficult to identify.

Squids in this group tend to be found mostly on the sea bottom, generally in sandy or muddy habitats where they lie buried during the day. They use their broad fins to bury themselves, and use their funnel to blow sand and arms to rake sand over their head. At night, they come out to hunt.

Some bobtail squids from the Family Sepiolidae have a rudimentary shell, many have light-emitting organs so that they glow in the dark. This actually camouflages them from bottom dwelling predators which look upwards for prey. The glowing body of a bobtail squid allows it to blend in a moonlit sky, instead of appearing as an obvious dark shadow. There are more than 50 species of bobtail squids found throughout the world from the Arctic sea to temperate and tropical waters.

Bottletail squids from the Family Sepiadariidae can produce slime from special glands on the underside of their body. They have kidney shaped (rather than circular) fins and lack light emitting organs. There are only about 8 described species of bottletail squids.

Changi, Jun 05

Pair of rounded fins.

Changi, Nov 07

Changi, Nov 07

Changi, Nov 07

*Species are difficult to positively identify without close examination. On this website, they are grouped by external features for convenience of display.
Bobtail squids on Singapore shores

Photos of Bobtail squids for free download from wildsingapore flickr

Distribution in Singapore on this wildsingapore flickr map

Changi, May 17
Photo shared by Marcus Ng on facebook.

Chek Jawa, Jun 03

Pasir Ris Park, Nov 08

Photo shared by Loh Kok Sheng on his blog.

Changi, Jun 05

Pulau Sekudu, Jun 17
Photo shared by Toh Chay Hoon on facebook.

Beting Bronok, Jun 17
Photo shared by Toh Chay Hoon on facebook.

Tanah Merah, Jul 09
Photo shared by James Koh on his blog.

Tanah Merah, Aug 09
Photo shared by James Koh on his blog.

Family Sepiolidae recorded for Singapore
from Tan Siong Kiat and Henrietta P. M. Woo, 2010 Preliminary Checklist of The Molluscs of Singapore.

  Family Sepiolidae
  Euprymna morsei

Sepiola birostrata
Sepiola trirostrata



  • Tan Siong Kiat and Henrietta P. M. Woo, 2010 Preliminary Checklist of The Molluscs of Singapore (pdf), Raffles Museum of Biodiversity Research, National University of Singapore.
  • Wee Y.C. and Peter K. L. Ng. 1994. A First Look at Biodiversity in Singapore. National Council on the Environment. 163pp.
  • Norman, Mark and Helmut Debelius, 2000. Cephalopods: A World Guide. ConchBooks, Germany. 319 pp
  • Chou, L. M., 1998. A Guide to the Coral Reef Life of Singapore. Singapore Science Centre. 128 pages.
links | references | about | email Ria
Spot errors? Have a question? Want to share your sightings? email Ria I'll be glad to hear from you!
wildfactsheets website©ria tan 2008