Description by Wayne Ellis:
Doto sp:
A undescribed species of Doto (Dendronotoidea:
Dotidae). The dendronotoidea is one of the four sub orders of Nudibranchia
and it resembles the aeloids in processing cerata. But unlike the aeolids
they have tubular sheaths that surround the rhinophores (rhinophoral sheaths),
a mid-lateral anus on the right side, with tufts of gills along the sides
of the broad mantle. The head usually has an oral veil (velum). If there
is a mantle skirt it is small. Size ranges from 1-30cm.They feed on soft
corals, anemones or hydroids.
In Fig.1. the hydroid is obscuring the rhinophores,
but they have the sheaths surrounding them like all the other dendronotoideans
and the cerata are arranged in multiple tiers, which is not (or rather
hardly ever) the case in aeolids. Carol Buchanan has slides of what is
probably this same new species from Split Solitary Island, Coffs Harbour.
Dr Richard Willan thinks this species of Doto is closest to, but different
from, the new species from Tasmania in Willan & Coleman's, Nudibranchs
of Australasia (1984: species no.166).
Dr Richard Willan in a recent personal communication
made this observation.
"...it's not an aeolid, but it is a wonderful
example of convergent evolution within the Nudibranchia. One finds dorids
that have tall papillae so they resemble aeolids, dorids that mimic other
(toxic) dorids, aeolids that mimic other aeolids, aeolids and dorids that
are camouflaged to resemble their food, arminoids that resemble dorids,
arminoids that resemble aeolids, and (as here) dendronotoids that resemble
aeolids, etc. It goes to show how bewildering nature can be. Understanding
these relationships is a challenge of our study."
This species was photographed during the 1987
Lord Howe Island Marine Fauna Survey conducted by Neville Coleman. It was
located on a hydroid and had possibly just laid eggs (the white mass above
it).
Photographic equipment: Nikonos lV-A with an
Aqua-Sea Strobe and 2-1 extension tubes.
References:
Willan & Coleman (1984) Nudibranchs of
Australasia
Willan R. (1999) pers comm. |
