Intertidal Invertebrates of the Monterey Bay Area, California

Compiled & photographed by Gary McDonald, Long Marine Laboratory, University of California, Santa Cruz

Flabellina trilineata (O'Donoghue, 1921)
Three-lined Aeolid
Mollusca: Gastropoda: Opisthobranchia: Nudibranchia: Aeolidina: Flabellinidae
Geographic Range: Lisianski Inlet, AK, to Bahia Tortugas, Baja California, Mexico. Synonyms: Coryphella fisheri, Coryphella piunca, Coryphella trilineata.
Back to: Aeolidina Back to: Intertidal Invertebrates of the Monterey Bay Area
Flabellina_trilineata_11_0104
Carmel Pt., Monterey Co., CA; 5 Mar 2008; 26mm total length.

Description: Ground color translucent greyish-white. A narrow, opaque white line extends longitudinally from tip of each oral tentacle, along its mid-dorsal surface to its base, where the two unite and pass posteriorly, mid-dorsally to tip of tail; similar lines extend longitudinally on either side of body, just ventral of cerata, from first row of cerata to just posterior of last row of cerata, where they unite with the median white line. Cerata in 6-8 transverse rows, cores usually red-orange, but quite variable, may be yellow to orange, cerata tips lighter, often white. Oral tentacles with yellow to deep cadmium orange on distal half in most specimens. Rhinophores colored as oral tentacles, with 7-10 complete annuli which alternate with more or less incomplete annuli which occur on posterior face of clavus. Anterior foot corners rather short and triangular.
Size: Typically about 20mm in length, but may exceed 30mm.
Notes: Feeds on hydroids such as Eudendrium californicum & Tubularia sp.

Flabellina_trilineata_1_0003
Carmel Pt., Monterey Co., CA; 25 Oct 2007; ~14mm total length.
Flabellina_trilineata_4_0032
Carmel Pt., Monterey Co., CA; 22 Dec 2007; 24mm total length
Flabellina_trilineata_6_0048
Carmel Pt., Monterey Co., CA; 22 Dec 2007; 19mm total length
Flabellina_trilineata_7_0054
Carmel Pt., Monterey Co., CA; 22 Dec 2007; 20mm total length
Flabellina_trilineata_8_0076
Carmel Pt., Monterey Co., CA; 19 Jan 2008; 30mm total length.
Flabellina_trilineata_14_0138
Scott Cr., Santa Cruz Co., CA; 9 Jan 2009: 7mm total length.

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