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First data on the ecology of Philipia mediterranea (Monterosato, 1872)
Ricardo Vega Luz
Any news whatsoever about this rare species endemic to the Mediterranean is extremely interesting and so I consider it important not only to publish the first photos of the live mollusc but also to give precise information about its habitat. It is rather difficult to obtain a live specimen of Philippia mediterranea (Monterosato, 1872 even here in the south of Spain, where this species seems to be less rare than in other places. In the last few months we have been very lucky to be able to keep two specimens, which were given to us live, in a 200 litre aquarium. One of these, the specimen we have had for the longer time, has been there for over six months and we have not noted the slightest weakening of the animal. Thanks to this we have been able to make some observations about its behaviour. As far as habitat is concerned, data collected shows that the species lives at a depth of about 40 metres on a substratum, in our opinion, of firm mud. Some specimens have been caught together with gorgonias. The zone where they are caught more frequently can be localized in an area between Torre del Mar (Málaga) and Herradura (Granata).   Together with P. mediterranea, other species have been collected: Aporrhais pespelecani (L., 1758), Pseudosimnia carnea (Poiret, 1789), Cymatium corrugatum (Lamarck, 1822) and Ocenebra erinaceus (L., 1758). It is interesting to note that, on the contrary to what we thought at the beginning, this species cannot be considered, on the basis of the data we possess, as a deep water species. I will not dwell on the description of the soft parts which are quite well visible in the photo. Here are the most interesting observations about the behaviour of the mollusc in an aquarium: The animal always lives on coarse or fine gravel, normally without burying itself in it or just partially doing so on some rare occassions. A few other times it was seen attached to the upper part of the glass, from which it detaches itself slowly, thanks to two threads of mucus which come from the foot, while, at the same time, it withdraws into the shell and closes itself in almost completely with the operculum. Its habits are decidedly nocturnal.
During the day and in the presence of artificial light it stays semiwithdrawn in its shell, and seems to be dead.
  In the dark the animal is more active, even though it has been very difficult for us to see it. We have just been able to note the change of its position in the aquarium from one day to another. So it was not possible for us to observe it while it was feeding and it is supposed that it does so during the night. In the considerable number of individuals found dead, it can be observed that one in four has a hole in on the body whorl of the shell. It can be deduced that members of the family Naticidae Gray, 1840, definitely including Tectonatica filosa (Philippi, 1844) are regular predators of P.mediterranea.


Note: On the bassis of recent literature (Melone L. & Taviani M., 1984 - Revisione delle Architectonicidae del Mediterraneo. Atti simposio Bologna 1982 - Lavori SIM 21), the correct binomial to use for this species of the Pleistocene (Sicilian), similar but distinct from lepida, while Basisulcata is the new genus proposed for this species (Melone & Taviani op. cit.), distinct from Philippia for radular and protoconch characters.

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La Conchiglia - The Shell
Year XXII - N. 250 - 252 January - March 1990