Factsheet for Tritonia myrakeenae from California

October 16, 2009
From: Jeff Goddard & Brenna Green

Hi Bill,

Here are some images and material for a Factsheet  for Tritonia myrakeenae Bertsch and Mozqueira, 1986 for the Forum.

Tritonia myrakeenae is a diminutive, cryptic tritoniid that ranges from the southern California bight (Bertsch and Mozqueira, 1986; personal observations) to Costa Rica (Camacho-Garcia et al. 2005). It occurs intertidally, usually in association with the undescribed, tan to pale salmon-colored, stoloniferous octocoral, Clavularia sp., on which it likely feeds (personal observations). The body is translucent, revealing the pale orange to red viscera, and often has a pair of opaque white blotches dorsally. According to Bertsch and Mozqueira (1986) it reaches a total length of 18 mm; specimens we have seen in southern California are typically 10 mm or less. We have included some photos of its food in a separate message [#22537].

Locality: Bird Rock, La Jolla, Intertidal, California, Pacific Ocean, 30 May 2009, Rocky shore. Length: 8 mm. Photographer: Brenna Green.

Tritonia myrakeenae lays small, coiled egg ribbons (http://slugsite.us/bow/nudwk111.htm), which as seen in the attached image, sometimes show gaps in the distribution of egg capsules (it is not clear if these gaps represent breaks in the egg stream during oviposition, or shifting of egg capsules after oviposition). The eggs average less than 80 microns in diameter and take 8 days (at 16 - 18 degrees C) to develop into planktotrophic veligers with type 1 coiled shells averaging about 125 microns in length at hatching (Goddard 2004, unpublished data).

Hans Bertsch and Antonio Mozqueira Osuna named this species in honor the eminent American Malacologist A. Myra Keen.

• Bertsch, H. & Mozqueira Osuna, A. (1986). A new species of Tritonia (Nudibranchia) from southern California and Baja California. The Nautilus 100(2): 46-49.
• Camacho-Garcia, Y., Gosliner, T.M. & Valdes, A. (2005). Field guide to the sea slugs of the tropical eastern Pacific. California Academy of Sciences, San Francisco, California.
• Goddard, J.H.R. (2004). Developmental mode in benthic opisthobranch molluscs from the northeast Pacific Ocean: feeding in a sea of plenty. Canadian Journal of Zoology 82(12): 1954-1968.

Best wishes,
Brenna Green and Jeff Goddard

goddard@lifesci.ucsb.edu

Dear Jeff & Brenna,

Thanks for this nice addition to the Forum

Best wishes,
Bill Rudman

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