young, 1.8 mm
Haminoea ovalis Pease, 1868
|Maximum size: 18 mm.
has a strongly inflated transparent shell without spiral
striae. The animal is translucent green variably spotted with orange
and purple. Younger animals are often darker than mature ones
with proportionately larger spots. As the animals mature, they develop
fine rust-brown flecks first on the foot, then on the rest of the body.
Rarely, the purple spots may be lacking. It can be distinguished from Haminoea
cymbalum by its extensive purple spotting and from Haminoea
sp. #1 by its smaller orange spots.
Haminoea ovalis is
a common nocturnal species found at highly protected to moderately
protected sites in rocky and mixed habitats as well as in Halimeda kanaloana beds. It
occurs at depths of < 1 to 12 m (< 3 to 39 ft). It is usually
associated with patches of the blue-green algae Lyngbya on which it
probably feeds. Copulating pairs are often found crawling together at
night with the head of the trailing animal overlapping the "tail" of
the other. (Note 1) It lays an elongate, white
to faintly greenish egg mass containing a "slinky-like" egg string and
attached by an adhesive surface. The egg masses usually acquire a
coating of sand or detritus in the field and hatch in about four days
in the laboratory.
Big Island, Maui, Oahu and Midway: widely distributed in the western
Pacific; also in the eastern Pacific.
Taxonomic notes: This species is probably listed in Severns, 20ll as Haminoea sp. 2 cf. ovalis.
Photo: CP: 17
mm: Hekili Point, Maui; Nov. 16, 2002.
Observations and comments:
1: Although not visible from the
top, the greatly elongated penis of the posterior animal is inserted
in the genital aperture of the first one while they are crawling. When
a pair was carefully collected on Sept. 30, 1997 they remained
"attached" for over 24 hours before separating.