August 29, 1999
From: Terry Gosliner
The main external characteristics for differentiating it from F. verrucosa is that the cerata are more distinctly arranged in rows in F. gracilis and there is a more prominent vestige of a notal brim in F. gracilis. Also F. gracilis has a sort of notched head between the junction of the oral tentacles and more elongate anterior margins of the foot. It is a bit difficult to see all these details in Betsey's photos, but I think that is what she has. Also she mentions that these animals were smaller than F. verrucosa, which is the case.
Alan Kuzirian's review of those species (I think that it was published in J. Moll. Stud. in about 1979) really clarified much of this historical confusion.
Flabellina gracilis from Maine, USA
From: Alan Shepard, August 28, 2003
Flabellina gracilis from Scotland
From: Jim Anderson, May 27, 2002
Flabellina gracilis & F. browni
From: Bernard Picton , July 22, 2001
Flabellina gracilis from the Netherlands
From: Peter H. van Bragt, September 4, 1999
From: Erwin Koehler, August 31, 1999
Flabellina gracilis? from NY
From: Betsey Hansen, August 27, 1999