June 30, 2001
From: Bernard Picton
I'm quite certain that your antipodean Janolus cf. hyalinus is not the same
as our NE Atlantic Janolus hyalinus. As you point out in your discussion the digestive gland in true J. hyalinus only extends halfway up the cerata and the pigmentation is quite different. I've seen about 30 animals over the years so I'd have some idea of the range of variation. The photograph of John Chuk's Victorian animal looks similar to ours, but Andrew Green's animals from New Zealand are certainly different.
Upper Right, Lower Left: July 1976 - Lundy Is., Bristol Channel, England. This is the specimen illustrated in Thompson and Brown, 1984 and collected in company with Greg Brown.
Lower Right: Aug 1980 - Lough Hyne (Ine), Co. Cork, SW Ireland (also from batch
of specimens mentioned in Thompson and Brown). Photos: Bernard Picton.
Picton, B.E., 2001 (Jun 30) Janolus hyalinus from Europe. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/4685
Thanks for adding some northern European input. I have included your information on feeding and egg laying to a separate message. When I get a chance I will prepare a more informative header page for this species.