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Cephalopyge trematoides

Cephalopyge trematoides
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Clade: Heterobranchia
Clade: Euthyneura
Clade: Nudipleura
Order: Nudibranchia
Clade: Dexiarchia
Family: Phylliroidae
Genus: Cephalopyge
Hanel, 1905
Species: C. trematoides
Binomial name
Cephalopyge trematoides
Synonyms
  • Ctilopsis
  • Dactylopus
  • Nectophyllirhoe
  • Boopsis
  • Bonneviia
  • C. mediterraneus
  • C. orientalis
  • C. picteti
  • C. michaelsarsi
  • C. arabica

Cephalopyge trematoides is a pelagic species of nudibranch. A free-swimming marine gastropod in the family Phylliroidae.Cephalopyge trematoides is the only known species in its genus (i.e. the genus is monotypic).

Cephalopyge is a contraction of cephalus (Greek: Κέφαλος Kephalos, "head") and pyge (πῦγή, "behind") referring to the position of the anus close to the head. The species epithet trematoides expresses a likeness to flukes.

C. trematoides grows to 2.5 cm in length. It swims at approximately 12 cm/s, by passing several undulatory waves down its body each second. It is flattened and transparent; its internal organs are visible.

Of the approximately 3000 species of nudibranch, the vast majority are benthic, only a couple are neustonic, and C. trematoides is very unusual in that it is pelagic. It is estimated to be one of only five planktonic nudibranch species (another epipelagic example is Phylliroe bucephala).

Further information (including photos):

film of Cephalopyge swimming


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