Relevant Synonyms Pyrgulina fischeri Hornung and Mermod, 1925 Misidentification - photo: Jeroen Goud, Naturalis, Leiden Thanks to Drs Bogi, Doria, Mienis and van Aartsen.

SHORT DESCRIPTION As for all the species of the genus Chrysallida, C. fischeri has an heterostrophic embryonic protoconch with a 120° inclined axis ("type B" according to van Aartsen, 1987); so that, being intorted, the apex appears hidden in the following whorl. Axial ribs are well marked, stronger than the fine and conspicuous spirals, covering the whole surface of each whorl. The suture is well marked and the columella is inclined to left, with a prominent tooth. color : white or cream. common size : the holotype measures 2.6 mm in length. DISTINGUISHING CHARACTERISTICS A clear columellar tooth, well distinguishable at an accurate observation, characterises this pyramidellid as belonging to the genus Chrysallida, instead of Turbonilla, which lacks columellar structures. Among the Mediterranean Chrysallida, this species most closely resembles C. decussata (Montagu, 1803), from which it differs in being more cylindrical: last whorl/total height ratio is rather ½ in C. fisheri and 2/3 in C. decussata. It also resembles the exotics Chrysallida maiae, which is larger and has a stouter outline, and Turbonilla edgari (Melvil, 1869), which has a different insertion of the protoconch whorls. BIOLOGY / ECOLOGY Pyramidellidae are ectoparasites, mainly of sedentary polychates and molluscs. habitat : records do not provide habitat information for the species in the Mediterranean. In Israel and Turkey the shells were found in 40-70 m and 0-12 m depth, respectively.

1st Mediterranean record Israel, 1979 [1974]. DISTRIBUTION Worldwide : Red Sea (van Linden and Eikenboom, 1992). Mediterranean : records are based only on shell findings from Israel, Haifa Bay in 1974 (van Aartsen and Carrozza, 1979) and Turkey, Gulf of Iskenderun (Micali and Palazzi, 1992) and Tasuçu (Buzzurro and Greppi, 1995). ESTABLISHMENT SUCCESS Rare. speculated reasons for success : - MODE OF INTRODUCTION Possibly via the Suez Canal. IMPORTANCE TO HUMANS None.

KEY REFERENCES Barash A. and Danin Z., 1986. Further additions to the knowledge of Indo-Pacific Mollusca in the Mediterranean Sea (Lessepsian migrants). Spixiana, 9(2): 117-141. Buzzurro G. and Greppi E., 1995. Note sul materiale tipico di origine lessepsiana della collezione Hornung & Mermod. Notiziario del CISMA, 17: 5-16. Micali P. and Palazzi S., 1992. Contributo alla conoscenza dei Pyramidellidae della Turchia, con segnalazione di due nuove immigrazioni dal Mar Rosso. Bollettino Malacologico, 28(1-4): 83-90.   van Aartsen J.J. and Carrozza F., 1979. Chrysallida fischeri (Horn. & Mer., 1925): a Red Sea species found at the Israeli Mediterranean coast. Bollettino Malacologico, 15(1-2): 29-30. van der Linden J. and Eikenboom J.C.A., 1992. On the taxonomy of the recent species of the genus Chrysallida Carpenter from Europe, the Canary Islands and the Azores (Gastropoda, Pyramidellidae). Basteria, 56: 3-63. FEEDBACK / COMMENTS TO AUTHORS

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