Abstract
The study of new material brings complementarydata on the crinoid fauna from the Saint-Céneré Formation. 12 species are described; 6 species and a genus are new. The difficulty of determining the systematic position of Idaeumocrinus n. gen. within the cladid inadunates raises the problem of the value of the anal plate characters associated with dorsal cup characters in the definition of suprageneric groups. The identification of isolated columnals of Tiaracrinus soyei Oehlert has been possible owing to the strong correlation that exists between calyx and columnal ornamentation; an important intraspecific variability in the columnal shape and the articular facet has been pointed out. Stabilization and anchorage by mean of stereomic spinose expansions have been discovered on the distal part of stem in Asperocrinus. The survival in the Devonian of the genus Carpocrinus has been established and the one of Neoarchaeocrinus is confirmed. The presence of Diamenocrinus stellatus Jaekel, a common species in the Rhenish massive, corroborates the extension of the Saint-Céneré Formation into the Middle Siegenian. The existence of Edrioasteroidea, represented by the genus Rhenopyrgus, is recorded for the first time in the Armoricain massive.
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