Home
Acknowledgments
Conventions
Glossary
Maps
References
Links
Articles
Thumbnails
Species list
Family
Next species
_______________
 
Additional Photos
 

pale
 

opaque

 

"tail" junction
 

interior

 


feeding
 

defecating
 


egg mass






 
Stylocheilus longicauda
(Quoy & Gaimard, 1825)
 
Stylocheilus longicauda
Maximum size:  about 55 mm.

Identification:  This sea hare has a bright yellow body decorated with pale blue and bright orange ocelli. Occasionally it may have faint brown spots. The "tail" is elongate and flattened.

Natural history:  Stylocheilus longicauda is a planktonic species found primarily on drifting debris (although it may also be found occasionally on mooring lines or buoys). The elongate, flattened "tail" allows it to cling tightly to its substrate. It is seldom seen around the main islands but  may be common at French Frigate Shoals and elsewhere in the leewards. As with other members of the genus, the ocelli may function as an aposematic signal. (Note 1) It lays a tangled, light yellow egg mass.

Distribution:  Big Island, Maui, Oahu, French Frigate Shoals and Kure: circumtropical.

Taxonomic notes:  It was first recorded in Hawaii from a lobster larvae collector at Kure by Scott Johnson on June 16, 1980.

Photo:  CP: 2006 CREEF expedition; French Frigate Shoals; Oct. 25, 2006.

Observations and comments:

Note 1:  The "blue spots with gold rings on a gold background" aren't as precisely matched to the "blue and gold ocelli on a cryptic background" found in the sea hares Stylocheilus striatus and Phycophila euchlora (as well as some unrelated mimics). However, all other members of the mimicry complex are benthic. That may account for the differences with the ocelli still serving as an aposematic signal. It's also possible that they're a neutral trait that's been retained from shared ancestors....
Thumbnails
Species list
Family Next species Top