Hilton's Aeolid

Phidiana hiltoni

Description 6

This aggressive aeolid is common from Marin County to points south. While the dark ceratal cores, red-banded rhinophores, and red "mustache" make it quite distinctive, the red mustache sets it apart from all our other aeolids. Note that it readily eats smaller nudibranchs, so if you remove it from a pool for photography, place it in its own container.

Description 7

This nudibranch grows to 50 mm, or a little more than 2 inches in length. The reddish or brownish line across its head is almost always present, and is very characteristic of the species.

This species can be confused with Hermissenda crassicornis, which is superficially similar in appearance.

Distribution 7

This species has a rather limited range of distribution, being found from the central California coast to Baja California, Mexico, and it is also found in the Gulf of Mexico. Recently, its range has been extending north and is now found north of San Francisco Bay.

Life habits 7

This aolid nudibranch species is considered to be rather aggressive, often biting and fighting with other nudibranchs, including members of its own species.

Sources and Credits

  1. (c) Ed Bierman, some rights reserved (CC BY), https://www.flickr.com/photos/edbierman/8666431029/
  2. (c) Robin Agarwal (ANudibranchMom on iNaturalist), some rights reserved (CC BY-NC), https://www.flickr.com/photos/30314434@N06/26870517812/
  3. (c) Ken-ichi Ueda, some rights reserved (CC BY-NC), http://www.flickr.com/photos/ken-ichi/2479381877/
  4. (c) Ken-ichi Ueda, some rights reserved (CC BY), uploaded by Ken-ichi Ueda, http://www.flickr.com/photos/18024068@N00/3030758017
  5. (c) Robin Agarwal (ANudibranchMom on iNaturalist), some rights reserved (CC BY-NC), https://www.flickr.com/photos/30314434@N06/25160601326/
  6. (c) Ken-ichi Ueda, some rights reserved (CC BY-SA)
  7. (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Phidiana_hiltoni

More Info

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