
Aglajidae is a family of often colorful, medium-sized, sea slugs, marine opisthobranch gastropod mollusks. These are not nudibranchs; instead they are headshield slugs, in the clade Cephalaspidea.

Philiopsis is a genus of often colorful, medium-sized sea slugs, marine opisthobranch gastropod mollusks. These are not nudibranchs; instead they are headshield slugs, in the clade Cephalaspidea.
Biuve fulvipunctata, the white-speckled headshield slug, is a species of sea slug or headshield slug, a marine opisthobranch gastropod mollusc in the family Aglajidae. This species is widespread in the Indian and Pacific Oceans but has invaded the Mediterranean Sea since 1961, despite apparently being absent from the Red Sea until recorded there in the 21st century. It is the only species in the monotypic genus Biuve.
Chelidonura is a genus of small, sometimes colorful, sea slugs. These are headshield slugs or cephalaspideans, marine opisthobranch gastropod mollusks in the family Aglajidae.

Chelidonura amoena is a species of sea slug, or "headshield slug", a marine opisthobranch gastropod mollusk in the family Aglajidae.

Chelidonura electra is a species of sea slug, a "headshield slug", a marine opisthobranch gastropod mollusk in the family Aglajidae. The species name comes from the daughter of Agamemnon, Electra, and the Greek goddess of the same name, meaning "shining", with reference to the brilliance of this slug.

Chelidonura hirundinina is a species of small and colorful aglajid sea slug, a shell-less opisthobranch gastropod mollusk in the family Aglajidae.

Chelidonura livida is a species of sea slug, or "headshield slug", a marine opisthobranch gastropod mollusk in the family Aglajidae.

Chelidonura pallida is a species of sea slug, or "headshield slug", a marine opisthobranch gastropod mollusk in the family Aglajidae.

Chelidonura punctata is a species of sea slug, or "headshield slug", a marine opisthobranch gastropod mollusk in the family Aglajidae.

Chelidonura sandrana is a species of sea slug, or "headshield slug", a marine opisthobranch gastropod mollusk in the family Aglajidae.
Chelidonura varians is a species of small sea slug, a marine opisthobranch gastropod mollusc in the order Cephalaspidea, the headshield slugs.

Mariaglaja inornata, also called the inornate headshield slug, is a species of sea slug or headshield slug, a marine opisthobranch gastropod mollusc in the family Aglajidae.

Melanochlamys is a genus of headshield slugs in the family Aglajidae. Despite the appearance of its species, this genus must not be confused with nudibranchs.
Navanax is a genus of sea slugs, marine opisthobranch gastropod mollusks in the family Aglajidae.

Navanax aenigmaticus common name the mysterious aglaja is a species of Navanax found in the Pacific Coast of Central America.

Navanax inermis, common name the California aglaja, is a large species of predatory sea slug, a marine opisthobranch gastropod mollusk in the family Aglajidae. Navanax is not a nudibranch, even though it somewhat resembles one; it belongs to a more ancient lineage of opisthobranchs called the cephalaspideans or head shield slugs and snails.

Odontoglaja is a genus of sea slugs, marine opisthobranch gastropod mollusks in the family Aglajidae.
Philinopsis speciosa, the blue-lined philinopsis, is a species of sea slug, a shell-less opisthobranch gastropod mollusc in the family Aglajidae. It is native to the Indo-Pacific region.

Philinopsis taronga is a species of small and colorful aglajid sea slug, a shell-less opisthobranch gastropod mollusk in the family Aglajidae. It has an Indo-Pacific distribution in southeastern Australia and northern New Zealand.
Tubulophilinopsis is a genus of medium-sized, sea slugs from the Indo-West Pacific belonging to the family Aglajidae.
Tubulophilinopsis gardineri, the Gardiner’s philinopsis, or Gardiner's headshield slug is a species of sea slug, a shell-less opisthobranch gastropod mollusc in the family Aglajidae. It is native to the Indo-Pacific region.