|Some authors place the
Opisthobranchia and Pulmonata within the clade
Heterobranchia. So, we've decided to include an addendum containing the
marine pulmonates so all the marine heterobranchs will be covered
on the site. Pulmonata contains most land snails and slugs, most fresh
water snails and only a few marine species. All of them are
hermaphrodites and most can absorb oxygen from the air via a modified
mantle cavity. Three families are known
from Hawaii: Onchidiidae (placed in the
Opisthobranchia in Kay, 1979), Ellobiidae (formerly Melampidae) and
Siphonariidae (placed in the Opisthobranchia in Grande, et. al., 2004 and Medina, et. al., 2011).
Kocot, et. al. (2011) recovers Opisthobranchia as paraphyletic with
respect to Pulmonata. That would suggest moving all the marine
pulmonates into the Opisthobranchia. However, they haven't been
traditionally considered opisthobranchs so we've decided to leave them in an addendum, at least for now.
The following information is derived primarily from reconciling Pilsbry
(1917-1921), Kay (1979), and Severns (2011) with each other and with our own material. So,
the IDs should be viewed as tentative, pending further work. Unlike for
the opisthobranchs, we haven't kept extensive notes on these
families--no running log of finds or detailed records of the source of
photographed animals. Therefore, we can't guarantee that it includes the
latest names and it may not be as comprehensive as the opisthobranch
|The family Onchidiidae
includes slug-like mollusks that live in the high intertidal. They lack
a shell and have tuberculate mantles. They feed on micro-algae. One
species in the genus Onchidium
is known from Hawaii.
|The family Ellobiidae
includes primitive pulmonates that live in the high intertidal and
supratidal zones. About 14 species are known from Hawaii including the genera Allochroa, Auricularia, Blaunereia, Laemodonta, Melampus and Pedipes.
|The family Siphonariidae
includes limpet-like species that inhabit the intertidal and subtidal.
At least three species are found in Hawaii in the genera Siphonaria and Williamia, the former intertidal
and the latter subtidal. They feed on micro-algae.
Medina, et. al., (2011) recovers the Siphonariidae as the sister group
to the Sacoglossa and they could be inserted in the main list as an
opisthobranch order under the name Siphonariacea (or be grouped with the Sacoglossa as the Siphoglossa). However, since they
haven't been traditionally considered opisthobranchs, we've decided to
leave them in the marine pulmonate addendum, at least for now.