''Atagema rugosa'', the rugby-ball dorid, is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

dorid ''Doridacea'' is a taxonomic grouping of dorid nudibranchs, shell-less marine gastropod mollusks.Bouchet P. & Rocroi J.-P. (Ed.); Frýda J., Hausdorf B., Ponder W., Valdes A. & Warén A. 2005''Classification and nomenclator of gastropod familie ...

nudibranch Nudibranchs () are a group of soft-bodied marine gastropod molluscs, belonging to the order Nudibranchia, that shed their shells after their larval stage. They are noted for their often extraordinary colours and striking forms, and they have b ...

, a marine

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusc Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Discodorididae Discodorididae is a Taxonomy (biology), taxonomic family (biology), family of sea slugs, specifically dorid nudibranchs, marine (ocean), marine gastropod mollusks in the superfamily Doridoidea.Bouchet, P. (2011). Discodorididae. Accessed through: ...

Distribution

This species was described from Cap l'Abeille, near

Banyuls-sur-Mer Banyuls-sur-Mer (; ) is a Communes of France, commune in the Pyrénées-Orientales Departments of France, department in southern France. Geography Location Banyuls-sur-Mer is located in the canton of La Côte Vermeille and in the arrondissemen ...

, France. It has been reported from the bay of

Gallipoli The Gallipoli Peninsula (; ; ) is located in the southern part of East Thrace, the European part of Turkey, with the Aegean Sea to the west and the Dardanelles strait to the east. Gallipoli is the Italian form of the Greek name (), meaning ' ...

, Italy, in the Mediterranean Sea and around the

southern African Southern Africa is the southernmost region of Africa. No definition is agreed upon, but some groupings include the United Nations geoscheme, the intergovernmental Southern African Development Community, and the physical geography definition b ...

coast on the Atlantic side of the

Cape Peninsula The Cape Peninsula () of South Africa is a generally mountainous peninsula that juts out into the Atlantic Ocean at the south-western extremity of the African continent. At the southern end of the peninsula are Cape Point and the Cape of Good ...

in 10–15 m of water. It is probable that the species known by this name in South Africa is actually a distinct species.

Description

''Atagema rugosa'' is described as a beige animal, darker in the lower parts of the mantle. Its tubercles are arranged in crests forming a network. It has five gills, with the three posterior held almost horizontal and the two anterior very small. The South African rugby-ball dorid is a small white

with black spots, a warty skin and a distinct longitudinal ridge down the middle of its back. It has eight

gill A gill () is a respiration organ, respiratory organ that many aquatic ecosystem, aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow r ...

s arranged around the anus and its

rhinophore A rhinophore is one of a pair of Chemoreceptor, chemosensory club-shaped, rod-shaped or ear-like structures which are the most prominent part of the external head anatomy in sea slugs, Marine (ocean), marine gastropod opisthobranch mollusks suc ...

s are

perfoliate The following terms are used to describe leaf plant morphology, morphology in the description and taxonomy (biology), taxonomy of plants. Leaves may be simple (that is, the leaf blade or 'lamina' is undivided) or compound (that is, the leaf blade ...

. It can reach a total length of 30 mm.Zsilavecz, G. 2007. ''Nudibranchs of the Cape Peninsula and False Bay''.

Ecology

The rugby-ball dorid feeds on

sponge Sponges or sea sponges are primarily marine invertebrates of the animal phylum Porifera (; meaning 'pore bearer'), a basal clade and a sister taxon of the diploblasts. They are sessile filter feeders that are bound to the seabed, and a ...

References

Discodorididae Gastropods described in 1951 Taxa named by Alice Pruvot-Fol {{Discodorididae-stub