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 by David Fenwick.

Sea slugs (Heterobranchia) - 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.

Heterobranchia (Subclass) > Euthyneura (Infraclass)

Acteonimorpha (Subterclass) > Acteonoidea (Superfamily) > Acteonidae (Family)

Acteon tornatilis (Linnaeus, 1758)
- Pink-banded barrel snail

Ringipleura (Subterclass) > 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

Tectipleura (Subterclass) > Aplysiida (Order) > Akeroidea (Superfamily) > Akeridae (Family)

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

Tectipleura (Subterclass) > Aplysiida (Order) > Aplysioidea (Superfamily) > Aplysiidae (Family)

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

Tectipleura (Subterclass) > 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)

Tectipleura (Subterclass) > Cephalaspidea (Order) > Cylichnoidea (Superfamily) > Cylichnidae (Family)

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

Tectipleura (Subterclass) > Cephalaspidea (Order) > Cylichnoidea (Superfamily) > Diaphanidae (Family)

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

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

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

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

Tectipleura (Subterclass) > 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)

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

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

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

Runcina coronata (Quatrefages, 1844) - Crowned runcina
Runcina ferruginea Kress, 1977
- A runcinid opisthobranch

Tectipleura (Subterclass) > Sacoglossa (Superorder) > Plakobranchoidea (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

Hermaea variopicta (A. Costa, 1869)
- A hermaeid sea slug

Tectipleura (Subterclass) > Sacoglossa (Superorder) > Plakobranchoidea (Superfamily)
> Limapontiidae (Family)

Alderia modesta (Lovén, 1844)
- Alder's slug, 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
- Flat limapontia

Limapontia senestra (de Quatrefages, 1844)
- Ridged acteon or Falmouth sea slug

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

Tectipleura (Subterclass) > Sacoglossa (Superorder) > Plakobranchoidea (Superfamily) > Plakobranchidae (Family)

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


Tectipleura (Subterclass) > Pteropoda (Order) >

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

Cavolinia tridentata (Forsskål in Niebuhr, 1775)
- A pelagic mollusc

Cavolinia uncinata (d'Orbigny, 1834) - A pelagic mollusc

Diacavolinia longirostris (Lesueur, 1821)
- A pelagic mollusc

Diacria quadridentata (Lesueur, 1821) - A pelagic mollusc

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

Clio pyramidata Linnaeus, 1767 - A pelagic mollusc

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

Cuvierina columnella (Rang, 1827) - Cigar pteropod

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

Limacina retroversa (Fleming, 1823)


From the authors collection of foreign shells,
species not recorded in the United Kingdom.

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

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

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

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

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.

Sea slugs Heterobranchia orders other than nudibranchia UK