on food sponge
probable egg mass
Doris nucleola Pease, 1860
|Maximum size: 18 mm.
usually has a blue body with a "double Y" shaped dusky-white
mark on its notum. The rhinophores are flecked with white and the
gills sometimes have a yellow rachis. Rarely, it may be dusky-yellow
with a blue "double Y" mark. (Note 1) The gills
are arranged in a circle.
Doris nucleola is
a moderately common species found under rocks in the low intertidal at
protected to moderately protected rocky sites. Rarely, it may be found
subtidally to depths of 5 m (16 ft). It's usually found associated with a
blue sponge (on which it probably feeds). It lays a cream, spiral
egg mass that hatches in five to six days in the laboratory.
Big Island, Maui, Oahu and Kauai: also known from Japan.
the species listed as Doriorbis
nucleola (Pease, 1860) in Kay, 1979. It is also illustrated in
Bertsch and Johnson, 1981 as the right hand animal in the photo
labeled Doriopsis pecten on
p. 35. It was first reported from Hawaii in Pease, 1860 (as Doris nucleola). Doris papillosa Pease, 1860 is
probably a synonym referring to the gray-blue form and animals
illustrated on the Sea Slug
Forum as Siraius immonda
(Risbec, 1928) may also be this species. There's some possibility that
the gray-blue and yellow forms could be different species.
Photo: CP: 13
mm: Hekili Point, Maui; Oct. 23, 2000.
Observations and comments:
1: We've only seen one animal with
the "reversed" color pattern (not photographed) but that appears to be
the most common color form in Japan. It was also apparently the form
originally described as Doris
nucleola in Pease, 1860.