Haminoeoidea is a

taxonomic Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...

superfamily SUPERFAMILY is a database and search platform of structural and functional annotation for all proteins and genomes. It classifies amino acid sequences into known structural domains, especially into SCOP superfamilies. Domains are functional, str ...

of small

sea snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...

s or bubble shells,

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

opisthobranch Opisthobranchs () is now an informal name for a large and diverse group of specialized complex gastropods which used to be united in the subclass Opisthobranchia. That taxon is no longer considered to represent a monophyletic grouping. Euopisth ...

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

s in the clade Cephalaspidea, the headshield slugs and bubble snails. These

cephalaspidea The order Cephalaspidea, also known as the headshield slugs and bubble snails, is a major taxon of sea slugs and bubble snails, marine gastropod mollusks within the larger clade Euopisthobranchia.Jörger K. M., Stöger I., Kano Y., Fukuda H., ...

ns do have distinct

anatomical Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having it ...

and morphological characteristics, but unfortunately many species were described only from empty shells. For proper clarification of the taxonomy, those species still need the research necessary to provide a good description of the external and internal anatomy of the living animal.

Description of live animal

The soft parts of the animals can retract completely or partially into their shells, and yet this offers them scant protection, because the

aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane. An opt ...

is rather wide and there is no operculum. Furthermore, the shell is very fragile and can easily be crushed by a predator. The cephalic shield of most species in this superfamily has two hind lobes that lie back on the front of the shell. The black eyes are usually buried just beneath the surface of the head.

Shell description

These bubble snails have thin, inflated shells ranging in shape from ovoid to flat and oval. They have an involute (sunken) spire.

Habitat

One can often find these bubble snails in enormous numbers, burrowing in mud on intertidal and sublittoral beds of

green alga The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/Streptophyta. The land plants (Embryophytes) have emerged deep in the Charophyte alga as ...

e such as for example, the

sea lettuce The sea lettuces comprise the genus ''Ulva'', a group of edible green algae that is widely distributed along the coasts of the world's oceans. The type species within the genus ''Ulva'' is ''Ulva lactuca'', wikt:lactuca, ''lactuca'' being Latin ...

, ''Ulva lactuca''.

Feeding habits

Haminoeid bubble snails are mostly

herbivorous A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...

Predators

Their

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

s include species of carnivorous aglajids such as ''

Navanax inermis ''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 belong ...

''.

Families, genera, species

Families, genera and species within the Haminoeoidea include: * Superfamily Haminoeoidea ** Family

Haminoeidae Haminoeidae, commonly known as the haminoeid bubble snail family, is a taxonomic family of sea snails, marine opisthobranch gastropod mollusks in the superfamily Haminoeoidea. The name of this family has long been controversial, and used to be ...

** Family Bullactidae Thiele, 1926: synonym of Haminoeidae Pilsbry, 1895 *** Genus ''

Bullacta ''Bullacta exarata'', common name the Korean mud snail, is a species of a sea snail or bubble snail, a marine gastropod mollusc in the family Haminoeidae, the bubble snails. ''Bullacta exarata'' is a commercially important mollusc which is used ...

'' Bergh, 1901 **** '' Bullacta exarata'' Philippi, 1848 – Distribution: China, Yellow Sea, Indo-Pacific ** Family Smaragdinellidae Thiele, 1925 – Oval yellow-green shell with sunken spire; very large aperture. *** Genus '' Phanerophthalmus'' A. Adams, 1850 **** '' Phanerophthalmus cylindricus'' (Pease, 1861) – Distribution: Indo-Pacific, Hawaii **** '' Phanerophthalmus smaragdinus'' Ruppell & Leuckart, 1828 – Distribution: tropical Indo-West Pacific, Hawaii – Length: 16 mm – Description: herbivore with a rather small cephalic shield; small enclosed mantle cavity ending in an exhalant siphon; small shell is partially enclosed in the mantle; color: brown to purple. *** Genus '' Smaragdinella'' A. Adams & Reeve, 1848: synonym of Haminoeidae Pilsbry, 1895 **** '' Smaragdinella algirae'' Forbes, 1844 **** '' Smaragdinella calyculata'' Broderip & Sowerby 1829 – Distribution: Japan, Indo-Pacific – Length: 8 mm – Description: green mantle with dark green spots **** '' Smaragdinella sieboldii'' A. Adams, 1864

References

* Rudman, W.B. (1972g) ''The herbivorous opisthobranch genera Phanerophthalmus'' A. Adams and ''Smaragdinella'' A. Adams. Proceedings of the Malacological Society of London, 40(3): 189-210, 11 figs.

External links

Oskars T.R., Bouchet P. & Malaquias M.A. (2015). A new phylogeny of the Cephalaspidea (Gastropoda: Heterobranchia) based on expanded taxon sampling and gene markers. Molecular Phylogenetics and Evolution. 89: 130-150
{{Authority control Euopisthobranchia