Selection: Cratena cf. lineata A

Cratena cf. lineata A (Eliot, 1905) [Hervia]

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cf. is an abbreviation from a Latin word (confer) and means 'refer to' or 'compare with', here it means it could possibly be Cratena lineata or perhaps something closely related, or at least similar in appearance.
Cratena cf. lineata A is characterized by its opaque white longitudinal lines on the cerata and two orange/red patches in front of the rhinophores. The long oral tentacles are translucent in the basal quarter, the apical three quarters are opaque white. The smooth rhinophores are basal translucent, followed by an opaque white region, the apex is translucent
It differs from Cratena lineata by the lack of opaque white longitudinal lines on the notum.
It differs from Cratena cf. lineata B by the lack of opaque white longitudinal lines on the notum, and by the orange/red patches in front of the rhinophores. This is Cratena sp. 1 in IPN at page 396:
Gosliner, Terrence M., David W. Behrens & Ángel Valdés. 2008. Indo-Pacific Nudibranchs and Sea Slugs. Sea Challengers Natural History Books.
Gig Harbor, Washington. 426pp.
Let me quote IPN: "Additional study is needed to determine whether individuals without lines on the notum represent a distinct species."
Pretty similar is also Cratena sp. 01 which lacks the orange/red patches in front of the rhinophores..
More informations on Cratena lineata are at Bill Rudman's Sea-Slug Forum!