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Post-Palaeozoic crinoids from northeast Spain ranging from the Ladinian (Middle Triassic) to the Ilerdian (lower Ypresian, early Eocene) are documented. Here we provide the first attempt to reconstruct the environmental distribution of these crinoids based on relatively complete material (mostly cups). Triassic forms are dominated by encrinids from outer carbonate ramps. Late Jurassic crinoids are dominated by cyrtocrinids, comatulids, millericrinids, and isocrinids, occurring either on sponge mounds and meadows or on soft substrates within middle to outer carbonate ramps. Aptian (Early Cretaceous) forms include nearly complete isocrinids which are found in extremely shallow environments represented by bioclastic carbonates and interspersed oyster-rich layers. Other Aptian occurrences come from more distal and deep environments and are composed solely of comatulids. Albian forms are dominated by cyrtocrinids and isocrinids associated with coral reefs. Late Cretaceous and Eocene crinoids include mostly bourgueticrinids (Comatulida) that are found either in outer ramp facies or associated with mid-ramp reef complexes. The later corresponds to one of the shallowest occurrence of bourgueticrinids in the Cenozoic. The palaeoecological data for fossil crinoids of northeast Spain contributes to reconstructing the history of the bathymetric distribution of articulate crinoids, supporting the idea that stalked crinoids were able to inhabit a wide range of shallow marine environments in the late Mesozoic and early Cenozoic.This is an open-access article distributed under the terms of the Creative Commons Attribution License (for details please see creativecommons.org), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Full text (1,047.2 kB)Powered by TCPDF (www.tcpdf.org)

A new genus and two new species of fossil hermit crabs (Anomura, Paguroidea) are described from the southern Pyrenean basins (Huesca, NE Spain). Parapetrochirus nov. with P. robustus n. gen., n. sp., as type species, comes from the lower Eocene (Ypresian) Roda Formation. It preserves both chelipeds exhibiting a notable heterochely, a larger left cheliped and a concavity without granulation in the inner upper portions. Eocalcinus gerardbretoni n. sp. comes from the highest levels of the Arguis Formation (Priabonian) in Yeste locality. This species is characterized by a hemispherical outline and a sinuous lower margin of the chela, which differs from the type species of the genus. The cheliped morphology of such species allows inclusion in the families Diogenidae and Calcinidae, respectively. Fossil paguroids are relatively rare in the Eocene of Spain, therefore, the description of these two new taxa increases the known diversity of this group. Parapetrochirus robustus n. gen., n. sp. inhabited siliciclastic substrates within a prodelta environment and E. gerardbretoni n. sp. was collected from the last levels of coral rudstones just below the continental influence of Yeste-Arrés Formation.

During fieldwork in a small outcrop of the lower Aptian Margas de Forcall Formation at La Cova del Vidre, hitherto known as the type locality of the anomuran Pagurus avellanedai, new decapod crustacean material has been recovered. In this newly recovered lot, two undescribed species of brachyuran have been recognised; there are here described as Rathbunopon tarraconensis and Pithonoton lluismariaorum. In addition, numerous remains of the anomuran P. avellanedai, enable an improvement of the original description of this taxon, and an analysis of associated ammonites from La Cova del Vidre has resulted in precise age calibration for the first time.

Semi-articulated paguroids are rare fossils, and there are only few records from Cenozoic strata. Here we present a new and exceptionally preserved hermit crab (Diogenidae) from the Eocene of Huesca (Spain) that preserves the anterior part of the carapace, together with appendages. Diogenes augustinus sp. nov. represents one of most completely preserved hermit crabs known to date, providing crucial information to understand the evolution of the family Diogenidae. It is characterized by poorly marked regions of shield, absence of Y-line and markedly unequal and robust chelipeds. The specimen is preserved out of its host shell suggesting rapid burial in siliciclastic strata of a prodeltaic environment.

A highly diverse fauna of dromioid brachyurans from the Serraduy Formation (lower Eocene) in the western Pyrenees (Huesca, Spain) is described and illustrated. Recorded taxa are Mclaynotopus longispinosus new genus new species, Torodromia elongata n. gen. n. sp., Basidromilites glaessneri n. gen. n. sp., ?Basidromilites sp., Sierradromia gladiator n. gen. n. sp., Kromtitis isabenensis n. sp., and ?Basinotopus sp. Other European outcrops have yielded dromioids in association with specific environments, likely coral and sponge reef and siliciclastic soft bottoms; but the present material constitutes the most diverse dromioid assemblage from the lower Eocene worldwide. These dromioids co-occurred with a rich invertebrate fauna and lived near coral–algal reef mounds. Sedimentological data suggest that most of the fauna accumulated in fore reef settings as a result of storm activity. The present material greatly increases the diversity of known dromioid crabs associated with Eocene reef environments. UUID: http://zoobank.org/aed8cafa-7c64-4e70-bd45-9f357fc37a28

A new species of Dynomene from the Priabonian (Upper Eocene) of the central Pyrenees in Aragón (Spain) is described as the first record of the genus from the Iberian Peninsula. The new species reveals close similarities to other dromioid species described from the Priabonian of Hungary. The panopeid Eoacantholobulus oscensis Ossó & Domínguez, 2017, from the same locality, is reviewed and transferred to the genus Sculptoplax, after comparisons with specimens of Sculptoplax rigida Müller & Collins, 1991 from the Priabonian of Italy. The present note again provides evi- dence of the close relationship between the Late Eocene decapod crustacean faunas of the western-most Tethys and the Pyrenean basins.