Preliminary report on new echinoderm Lagerstatten from the Upper Ordovician of the eastern Anti-Atlas, Morocco.
8 pages (p.23-30); International audience; Four distinct echinoderm Lagerstatten have recently been discovered in the Upper Ordovician of the eastern Anti-Atlas, Morocco. They have yielded hundreds of exquisitely preserved specimens. Their taphonomy and associated lithology both suggest rapid, in situ burial. Here we discuss the diverse range of assemblages represented and their significance to the diversity of echinoderms in the Lower Palaeozoic. The oldest assemblage (Izegguirene Formation, lowermost Caradoc) is dominated by eocrinoids, large ophiuroids, and mitrate stylophorans associated with rare crinoids. It shows strong similarities with slightly older faunas described from the under…
Middle Cambrian Gogiid Echinoderms from Northeast Spain: Taxonomy, Palaeoecology, and Palaeogeographic Implications
Gogia parsleyi Zamora sp. nov. and Gogia sp. are described from two different echinoderm assemblages, both from the middle Cambrian of the Murero Formation (Iberian Chains, NE Spain). Gogia parsleyi is reconstructed and described on the basis of fifteen complete or partial specimens and numerous isolated plates. It is characterised by spiralled brachioles, simple epispires, sometimes covered by stereomic domes or tiny cover plates, and by thecal plates arranged in subregular circlets. This gogiid population comprises juveniles, advanced juveniles and mature individuals. The material was found in the upper part of the Murero Formation (upper Caesaraugustian—lower Languedocian). Gogia sp. is …
A Middle Cambrian edrioasteroid from the Murero biota (NE Spain) with Australian affinities
Abstract A Middle Cambrian edrioasteroid belonging to the genus Cambraster is described from the Middle Cambrian Murero biota (Cadenas Ibericas, NE Spain). Up to now, this genus was known only from Australia and France. This represents the first record of the class Edrioasteroidea in the Cambrian of Spain. Moreover, preliminary results on the diversity and biostratigraphic position of Cincta, Eocrinoidea and Edrioasteroidea from this area are reported.
A new Alokistocaridae Resser, 1939 (Trilobita) from the middle Cambrian of Spain
A new trilobite species, Schopfaspis? graciai, from the middle Cambrian of Spain is the first member of Alokistocaridae reported from west Gondwana. A cladistic analysis of this trilobite and other Gondwanan trilobites of possible alokistocarid affinities (Schopfaspis granulosa, Chelidonocephalus anatolicus, Derikaspis toluni, Kounamkites multiformis) suggests that this family can be divided into two subfamilies: Alokistocarinae and Altiocculinae. Schopfaspis? graciai nov. sp. and Schopfaspis granulosa are assigned to the subfamily Altiocculinae laying in a more basal position than Altiocculus species. The cladistic analysis also demonstrates a possible relationship of Chelidonocephalus ana…