New internally structured decapod microcoprolites from Germany (Late Triassic/Early Miocene), Southern Spain (Early/Middle Jurassic) and Portugal (Late Jurassic): Taxonomy, palaeoecology and evolutionary implications

Fossil faecal pellets with internal structures are described from non-marine environments for the first time. In the Late Triassic Lehrberg Beds (Middle Keuper, Carnian) of Germany, the oldest stratigraphic record of the form genusHelicerina Brönnimann &Masse,Helicerina keuperina Seegis n. sp., occurs.Favreina kalankyra Ebli from the Norian Hauptdolomit Formation is also attributed to this genus. Another new speciesof Helicerina, H. ruttei Schweigert n. sp., is described from the Early Miocene calcareous freshwater tufas of Southern Germany. It is attributed to the brachyuran freshwater crabProballaya quenstedti (Zittel) which occurs abundantly at the same locality. Hence, the coprolite genusHelicerina is the product of brachyuran decapods or their Triassic ancestors, and not of anomuran decapods as thought before. From younger Early to Middle Jurassic pelagic ferrugineous limestones of the Subbetic area (Southern Spain), the new speciesFavreina belandoi Fels n. sp. is described besidesHelicerina siciliana Senowbari-Daryan, Schäfer &Catalano, and the better known speciesPalaxius salataensis Brönnimann, Cros &Zaninetti. The number of canals withinFavreina belandoi varies but is clearly correlated with different ontogenetic stages of the same producer. From the Late Jurassic of Portugal, the new speciesPetalina hexalunulata Leinfelder n. gen. n. sp. is reported. It co-occurs withFavreina prusensis (Paréjas). The new genusPetalina is distinct fromFavreina by its hemispherical cross sections of the canals. In Portugal, both species are restricted to intrajurassic marine karstic fissures of the reefal Ota Limestone.