Acta Palaeontologica Polonica

The earliest record of pylochelid hermit crabs from the Late Jurassic of southern Poland, with notes on paguroid carapace terminology

René H.B. Fraaije, Wiesław Krzemiński, Barry W.M. Van Bakel, Ewa Krzemińska, and John W.M. Jagt

Acta Palaeontologica Polonica 57 (3), 2012: 647-654 doi:

Strata with cyanobacterial−sponge buildups of Middle to Late Oxfordian (Late Jurassic) age in the southern Polish Uplands document the earliest known members of the Pylochelidae. Two new Late Jurassic species of “symmetrical” hermit crabs, Ammopylocheles robertboreki and Jurapylocheles iwonae, are described.Anew term, the massetic region, is introduced to describe the equivalent in paguroids of the hepatic region in brachyuran carapaces, because in the former, this region does not reflect the position of the liver but rather an attachment zone of the mandibular muscles.

Key words: Paguroidea, Pylochelidae, new species, massetic region, evolution, Oxfordian, Poland.

René H.B. Fraaije [], Oertijdmuseum De Groene Poort, Bosscheweg 80, NL−5283WB Boxtel, the Netherlands; Wiesław Krzemiński [], Ewa Krzemińska [], Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, ul. Sławkowska 17, PL−31−016 Kraków, Poland; Barry W.M. Van Bakel [], Oertijdmuseum De Groene Poort, Bosscheweg 80, NL−5283 WB Boxtel, the Netherlands; and, Nederlands Centrum voor Biodiversiteit (Naturalis), P.O. Box 9517, NL−2300 RA Leiden, the Netherlands; John W.M. Jagt [], Natuurhistorisch Museum Maastricht, de Bosquetplein 6−7, NL−6211 KJ Maastricht, the Netherlands.

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