As with other members
of suborder Arminacea,
the anus is not
on the midline of the dorsum
but instead is on a conspicuous papilla
on the posterior third of the right side of the dorsum.
have no sheath and cannot be completely retracted. This
translucent grayish-white, salmon, or light purple with bold white
on some edges of the flattened cerata
plus around the margin of its large frontal
veil, down the rear dorsal surface of its foot, and between
There is also an opaque white line down the inner margin of the shaft
and across to the opposite rhinophore.
Length usually to 4 or 5 cm but may range up to 18 cm.
albolineata Mac Farland
in Cockerell & Eliot, 1905 (or Eliot, 1905)
Common name(s): White-lined Dirona, Frosted nudibranch, Alabaster
albolineata from Coffin
Rocks, depth about 12 m.
|(Photo by: Kirt Onthank,
How to Distinguish from
many Arminaceans such as this species often make them look a lot like Eolid
nudibranchs, but they can be distinguished from Eolids
have the anus on a
the rear third of the body (right side) while Eolids
have it on the anterior third of the body (right side). Dirona
aurantia has similar-shaped cerata
but the overall color is orange, it has no white line on its frontal
veil, on its tail, or between its cerata,
and it has scattered white spots.
Alaska to San Diego, CA; Japan, East Russia
Intertidal to 37 m.
Usually on rocks, occasionally
fall off easily. Feeds on small snails such as Margarites
pupillus and Lacuna
by cracking the shells with its jaws. Also feeds on sea
and bryozoans (photo).
mass contains about 350,000 eggs.
and Fairbanks, 1966 (as Dirona
and Carlton, 1975
and Brusca, 1978
and Nybakken, 1980
et al., 1980
et al., 1985
General Notes and
abundances, unusual behaviors:
This individual is grazing on a bryozoan. Photo by Kirt
|This nudibranch exists in several
For example, the two nudibranchs below were found at a minus tide on
Head in late October, 2007. Although Kozloff's key says this
is not orange, these two individuals are marked just like D.
and NOT like D. aurantia yet they have orange on them.
orange comes from something they have been eating (note that one is
mainly in the cerata in one individual) or could they be
by Dave Cowles, October 2007
This individual is crawling along the edge of a tide pool at low tide,
Cape Flattery. Photo by Dave Cowles, July 2008
Authors and Editors of Page:
Dave Cowles (2007): Created original page
CSS coding for page developed by Jonathan Cowles (2007)