March 1, 2004
From: Jussi Evertsen
Following Sakkies's message [#12321]:
This is more like an anecdote to the topic of an arminid nudibranch appearing in large numbers and not being seen since. Here in the Trondheimsfjord we have had a peculiar observation of Armina loveni. According to Dons (1933) it appeared for the first time in 1933 (after 13 years of continuous survey). It was then a common catch from 1933 to 1939 (Odhner 1939). Since then we have not seen this species from the Trondheimsfjord, although is assumed in the literature to feed on the sea pen Virgularia mirabilis, which is quite common in the fjord.
It might be that A. loveni has a reproductive limit this far up the Norwegian coast, and that it in the 1930's had had a sucessful survival of offspring for a time. According to Dons (1930), the shallow water temperature of the fjord from 1925 to 1930 were higher than normal. The food seems abundant, so we might have to wait for another "warm" period for it to appear.
• Dons, C. 1934. [for 1933]. Zoologische Notizen XXIV. Uber die Verbreitung der Pleurophyllidia loveni. Det Kongelige Norske Videnskabers Selskabs Forhandlinger, 6(48): 183-184.
email@example.comEvertsen, J., 2004 (Mar 1) Re: Juvenile shape compared to an adult's. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/12330