An educational resource dedicated mainly to the photography
and diversity of marine life that can be found in coastal waters
and intertidal areas of Great Britain and Ireland.

Sea slugs (Opisthobranchia Orders other than Nudibranchia)
UK recorded non-native species or non-native invasive species are included within the main list species. Foreign shells, where included, have their own section below the main list of UK recorded species.

The author of this website is the curator of a mollusc collection held by the late Stella Turk C.B.E.. Many of the images on the following pages are of shells from this collection which is being used for both reference and research purposes.

Anaspidea (Order) > Akeroidea (Superfamily)
> Akeridae (Family)

Akera bullata O. F. Müller, 1776 - Soft bubble-shell

Anaspidea (Order) > Aplysioidea (Superfamily)
> Aplysiidae (Family)

Aplysia depilans Gmelin, 1791 - Depilatory sea hare
Aplysia punctata (Cuvier, 1803) - Common sea hare

Cephalaspidea (Order) > Bulloidea (Superfamily)
> Retusidae (Family)

Retusa alba (Kenmacher)
Retusa mammillata (Philippi, 1836)
Retusa obtusa (Montagu, 1803)
Retusa truncatula (Bruguière, 1792)
Retusa umbilicata (Montagu, 1803)

Cephalaspidea (Order) > Diaphanoidea (Superfamily)
> Cylichnidae (Family)

Cylichna cylindracea (Pennant, 1777)
- Cylindrical bubble-shell

Cephalaspidea (Order) > Diaphanoidea (Superfamily)
> Diaphanidae (Family) > Diaphaninae (Subfamily)

Diaphana minuta T. Brown, 1827 - Glassy bubble-shell

Cephalaspidea (Order) > Haminoeoidea (Superfamily)
> Haminoeidae (Family)

Haminoea hydatis (Linnaeus, 1758)
- Southern bubble-shell

Haminoea navicula (da Costa, 1778) - A Bubble-shell

Cephalaspidea (Order) > Philinoidea (Superfamily)
> Philinidae (Family)

Philine catena (Montagu, 1803)
Philine denticulata (Adams J., 1800) syn. Ossiania nitida
Philine punctata (Adams J., 1800) syn. Ossiania alata
- Dotted lobe-shell

Philine quadrata (Wood S., 1839) syn. Ossiania quadrata
Philine quadripartita Ascanius, 1772 - Lobe shell
Philine scabra (Müller, 1784)

Cephalaspidea (Order) > Philinoidea (Superfamily)
> Scaphandridae (Family)

Scaphander lignarius (Linnaeus, 1758)
- Woody Canoe-bubble

Pleurobranchomorpha (Order) > Pleurobranchoidea (Superfamily) > Pleurobranchidae (Family)

Berthella plumula (Montagu, 1803)
- Yellow-plumed or Side-gilled sea slug

Pleurobranchus membranaceus (Montagu, 1815)
- Rough side-gilled sea-slug

Runcinacea (Order) > Runcinoidea (Superfamily)
> Runcinidae (Family)

Runcina coronata (Quatrefages, 1844) - Crowned runcina

Sacoglossa (Order) > Plakobranchacea (Suborder) > Limapontioidea (Superfamily) > Hermaeidae (Family)

Hermaea bifida (Montagu, 1815) - Crimson hermaea
Hermaea cantabra Caballer & Ortea, 2015
- A hermaeid sea slug

Hermaea paucicirra Pruvot-Fol, 1953
- A hermaeid sea slug

Sacoglossa (Order) > Plakobranchacea (Suborder) > Limapontioidea (Superfamily) > Limapontiidae (Family)

Alderia modesta (Lovén, 1844)
- A limapontiid opisthobranch

Calliopaea bellula d'Orbigny, 1837 - A limapontiid sea slug

Limapontia capitata (O. F. Müller, 1774) - Black limapontia
Limapontia depressa Alder & Hancock, 1862
- A limapontiid opisthobranch

Limapontia senestra (de Quatrefages, 1844)
- The Falmouth sea slug

Placida dendritica (Alder & Hancock, 1843)
- Green hermaea

Sacoglossa (Order) > Plakobranchacea (Suborder) > Plakobranchoidea (Superfamily) > Plakobranchidae (Family)

Elysia viridis (Montagu, 1804)
- Green elysia, Sacoglassan or Solar-powered sea slug

Thecosomata (Order) > Euthecosomata (Suborder) > Cavolinioidea (Superfamily) > Cavoliniidae (Family)

Cavolinia tridentata (Forskal, 1775) - A Pelagic mollusc
Cavolinia uncinata (d'Orbigny, 1834) - A Pelagic mollusc

Diacavolinia longirostris (Blainville, 1821)
- A Pelagic mollusc

Diacria quadridentata (Blainville, 1821) - A Pelagic mollusc

Thecosomata (Order) > Euthecosomata (Suborder) > Cavolinioidea (Superfamily) > Cliidae (Family)

Clio pyramidata Linnaeus, 1767 - A Pelagic mollusc

Thecosomata (Order) > Euthecosomata (Suborder) > Cavolinioidea (Superfamily) > Cuvierinidae (Family)

Cuvierina columnella (Rang, 1827) - Cigar Pteropod

Thecosomata (Order) > Euthecosomata (Suborder) > Limacinoidea (Superfamily) > Limacinidae (Family)

Limacina retroversa (Fleming, 1823)

[unassigned] Heterobranchia (Infraclass)
> Acteonoidea (Superfamily) > Acteonidae (Family)

Acteon tornatilis (Linnaeus, 1758) - Acteon shell


Other members of the Opisthobranchia
(From the authors collection of foreign shells)

Cephalaspidea (Order) > Haminoeoidea (Superfamily) > Haminoeidae (Family)

Haminoea orbignyana (Férussac, 1822)
- A Bubble shell (Spain)

Thecosomata (Order) > Euthecosomata (Suborder) > Cavolinioidea (Superfamily) > Creseidae (Family)

Styliola subula (Quoy & Gaimard, 1827)
- A Creseidae opisthobranch (Canary Islands)

Lamellaria species, velutinids, look very much like sea slugs but are infact marine snails. Images are listed under the section 'Cowries and Velutinids'. Images of the Celtic sea slug, Onchidella celtica, can be found under Pulmonata.

Please send all Cornish records of marine molluscs, with images if possible, to David Fenwick. I will make sure records are collated and passed on to the national recorder at the Conchological Society of Britain and Ireland. I will also hold a set of records for use by other Cornish conchologists, researchers, and the Marine Biological Association. This is to ensure that open source free to use data gets on national databases.

European Names, Sea slugs, Nudibranches, Hinterkiemerschnecken, Limaces, Opistobranquios, Opistobranchi, Molluscs, Weichtiere, Weekdieren, Mollusques, Moluscos, Molluschi.

Also see the following external links -
Marlin (Mollusca Page)

Sea Slug Sea Hare and Bubble Shell Images Nudibranch UK