sea hares text index | photo index
Phylum Mollusca > Class Gastropoda > sea slugs > Order Anaspidea
Geographic sea hare
Syphonota geographica
Family Aplysiidae
updated May 2020

Where seen? This chubby delicately patterned sea hare is seasonally common on our Northern shores, among seagrasses. Sometimes large numbers are seen, at other times, not at all. Often found half buried in the soft sediment, but sometimes crawling in the open, especially near sunrise or at night. It is also known as Paraplysia geographica.

Features: 8-12cm. Body large, heavy and smooth. With two pairs of tentacles: one pair of oral tentacles forming flap at the front of the body. When compared with sea hares of the genus Aplysia, sea hares of the genus Syphonota have relatively small rhinophores which are close together and situated further back from the head almost between the long 'wings' or parapodia. When submerged, these wings are held high. It is said that they can swim with their parapodia.
Usually olive or yellowish greenish with tiny white spots forming patterns with fine line horizontal lines along the body.

Sometimes confused with the Spotted sea hare which has a pattern of tiny white spots that form patches and doesn't have fine horizontal lines.

Changi, Jun 05

Tiny rhinophores near one another,
held between parapodia.

Thin internal shell.
Changi, Jun 07
Baby sea hares: It lays long tangles of pink egg strings among seaweeds and seagrasses.

What does it eat? It is believed to feed on brown seaweeds, but in our observations, these animals seem more abundant during blooms of the green sea lettuce seaweed (Ulva sp.).

Laying egg string
Changi, Jun 05

Half buried in soft sediment.
Changi, Apr 12

Swimming sea hare!
Cyrene Reef, Nov 11

Geographic sea hares on Singapore shores
On wildsingapore flickr

Other sightings on Singapore shores

East Coast Park, May 16
Photo shared by Ywee Chieh on facebook.

Tuas, Mar 15
Photo shared by Loh Kok Sheng on his blog.

Cyrene Reef, Aug 11
Photo shared by Neo Mei Lin on her blog.

Cyrene, Jun 20
Photo shared by Loh Kok Sheng on facebook.

Links References
  • 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.
  • Coleman, Neville. 2001. 1001 Nudibranchs: Catalogue of Indo-Pacific Sea Slugs. Neville Coleman's Underwater Geographic Pty Ltd, Australia.144pp.
  • Humann, Paul and Ned Deloach. 2010. Reef Creature Identification: Tropical Pacific New World Publications. 497pp.
  • Gosliner, Terrence M., David W. Behrens and Gary C. Williams. 1996. Coral Reef Animals of the Indo-Pacific: Animal life from Africa to Hawaii exclusive of the vertebrates Sea Challengers. 314pp.
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