young, 3 mm
Elysia sp. #7
|Maximum size: 8 mm.
a small species with low parapodia that usually form two
chimneys. The body is cream with peach patches and there are often
irregular black patches on the sides of the head. Irregular patches of
pigment may also be present on the sides of the parapodia and some animals have extensive iridescent flecks.
(Note 1) It's distinctive in having large, though variable, downward-sloping
tubercles on the sides of the parapodia. (Note 2)
Elysia sp. #7 is a moderately
plakobranchid that is found on rocky bottoms in
moderately protected to moderately exposed locations at depths of <
1 to 5 m (< 3 to 17 ft). It jerks its
parapodia intermittently while crawling.
Big Island, Maui, Oahu and Kauai: possibly known from Madagascar.
It was first
in Hawaii from Maluaka, Maui by CP on Nov. 15, 1995.
Photo: CP: 7
mm; large tubercles, light: Hekili Point, Maui; June 3, 2003.
Observations and comments:
1: The lack of green pigment in the
digestive gland branches in highly iridescent animals might suggest that
they haven't fed recently or aren't retaining chloroplasts. Perhaps,
the iridescent flecks are only deposited (or only become visible?) when that happens...
Note 2: Although speculative, the
distribution on Maui suggests that animals with larger tubercles may
areas with higher surge. Perhaps, they enlarge during development in
response to hydrological stress?