Rissoa (Rissostomia) membranacea (J. Adams, 1797) (Gastropoda: Prosobranchia: Rissoidae) in Puck Bay (southern Baltic Sea)
In the paper the author describes the morphology and anatomy of the Rissostomia species inhabiting Puck Bay. A detailed description of the shell and its variability (including the colour spots and ribs occurring very rarely) is given. Then the author describes the head pigmentation, variable and quite uncharacteristic. The concise descriptions of the soft parts morphology, ctenidium, radula and male reproductive organs are given. The variability of the giant penis is described, as well as the structure of the female reproductive organs. Then the author compares the Polish Rissostomia with the drawings and descriptions of R. membranacea given in the literature, as well as with the specimens of the species from the localities outside the Baltic Sea. He establishes that the Polish Rissostomia belong to Rissoa membranacea which is an extremely polymorphic species. key woRDs: shell variability, pigmentation, ctenidium, radula, reproductive organs, penis http:/dx.doi.org/10.12657/folmal.002.003 Folia Malacol. 2: 53 61 Folia Malacologica 2/1988 was originally published as No. 1112 of Scientific Bulletins of University of Mining and Metallurgy, Cracow. This digitalised version was prepared by the Association of Polish Malacologists and first published on line on December 30th, 2016. ZESZYTY NAUKOWE AKADEMII G6RNICZO HUTNICZEJ IM. ST ANISlAWA STASZICA Nr 1112 Folia Molacologica z. 2 Krak6w 1988 ANDRZE.J F.ALNIOWSKI RISSOA (RISSOSTOMIA) MEMBRANAOEA ADAMS, 1797) (GASTROPODA: PROSOBRANCHIA: RISSOIDAE) IN PUCK BA V (SOUTHERN BALTIC SEA) Ab s t r a c rt In the paP,er the author describes the morphology and anatomy of the Rissos.tomia species iohabi ting Puck Bay. A detailed des.cription of the shell and ~ts variability {Including tne colour spots and ribs ocC.tJrring very r.arely) is @l*ven. Then the a~,tthor ~e.scribes the head pigmentation, var1able and quite uncharacteristic. The concise descriptions of the soft parts morphology, ctenidium, radula and male reproductive organs are given. Jha v*riability of the giant pe~is ~s described, aq well as the structure of the female reproductive organs. Then t!'le authot compares the Polfsh Rissostomia with the drawings and descriptions of R. membraoacea given in .the literature, as well as with the specimens Bf the species from the localities outside the Baltic Sea. He establishes that the Polish Rissostomia belong to Rissoa membrana~ea which is an extremely polymorphlc species.