thiolliericrinid crinoids from the lower cretaceous of crimea

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THIOLLIERICRINID CRINOIDS FROM THE LOWER CRETACEOUS OF CRIMEAbyVladim ir G. KLIKUSHIN *AbstractThe family Thiolliericrinidae (Oxfordian - Hauterivian)includes the stalked crinoids of the order Comatulida,inhabiting reef fades. Remains of 12 thiolliericrinidspecies (10 among them are new) belonging tosix genera (Thiolliericrinus, Burdigalocrinus, Loriolicrinus,Conoideocrinus nov. gen., Umbocrinus nov.gen., and Heberticrinus nov. gen.) from the Berriasianand Valanginian of Crimea are described. On thebasis of an extensive material (hundreds of calyxes,centr odor sals, brachials and columnals) the skeletalmorphology, the ontogenetic variations of the calyxesand the phylogeny of the Thiolliericrinidae arereconstructed. The family taxonomy is defined moreexactly regarding new morphological data.RÉSUMÉLa famille Thiolliericrinidae (Oxfordien - Hauterivien)comprend les crinoïdes pédonculés de l’ordreComatulida, vivant dans des milieux récifaux. 12espèces (dont 10 sont nouvelles) de Thiolliericrinidaesont décrites du Berriasien et du Yalanginien de laCrimée. Ces espèces appartiennent à six genres :Thiolliericrinus, Burdigalocrinus, Loriolicrinus,Conoideocrinus nov. gen., Umbocrinus nov. gen. etHeberticrinus nov. gen. L’étude d’un matériel abondant(des centaines de coupes dorsales, de pièces centrodorsaleset brachiales, de columnales) permet unediscussion sur la morphologie du squelette, les variationsontogénétiques des coupes dorsales et la phylogéniedes Thiolliericrinidae. D ’après les nouvellesdonnées morphologiques la taxonomie de la familleest précisée.KEY-WORDS : CRINOIDEA, ARTICULATA, COMATULIDA, THIOLLIERICRINIDAE, TAXONOMY, NOMENCLATURE, MORPHOLOGY, ONTOGENY, PHYLOGENY, CRETACEOUS, USSR.MOTS-CLÉS : CRINOÏDES, ARTICULATA, COMATULIDA, THIOLLIERICRINIDAE, TAXONOMIE, NOMENCLATURE, MORPHOLOGIE, ONTOGENIE, PHYLOGENIE, CRÉTACÉ, URSS.* Leningrad Mining Institute, 199026 Leningrad, USSR.Geobios, n° 20, fasc. 5 p. 625-665, 18 fig., 2 tab l., 1 pl. Lyon, octobre 1987
TABLE OF CONTENTS1 - Introduction........................................................p. 6262 - Localities and materials.....................................p. 6263 - Term inology........................................................p. 6294 - Taxonomie description....................................p. 631Genus Solonaerium E t a llo n emend.Ra s m u s s e n ...........................................................p. 633Genus Thiolliericrinus E t a l l o n .....................p. 634Genus Burdigalocrinus Ja e k e l .......................p. 639Genus Loriolicrinus J a e k e l .............................p. 641Genus Conoideocrinus nov. gen.......................p. 644Genus Umbocrinus nov. gen.............................p. 646Genus Heberticrinus nov. gen...........................p. 6465 - Reconstruction of the skeleton..................... ..p. 652Root formations ............................................... ..p. 652Stem ......................................................................p. 653A rm s .................................................................... ..p. 6536 - Ontogenetic variations of the calyxes ......... p. 6567 - Origin of the Thiolliericrinidae..................... p. 6578 - Development of the Thiolliericrinidae......... p. 658Acknowledgements.............................................. p. 660R eferences.............................................................. p. 6601 — INTRODUCTIONSea-lilies of the Comatulida are freely mobile formswhich are widely distributed in the modern seas.Calyxes of these crinoids, consisting of five radiais,five basais and one centro-dorsal plate bearing cirri,are also found in the fossil record.However, one peculiar exception exists in that largegroup : the fossil family Thiolliericrinidae. The representativesof this family were stalked and led a fixedlife. The thiolliericrinid thecae were constructed likethe true Comatulida, but their columns showsimularities with the Bourgueticrinida stems. Suchcombination of the features lead to complicated problemsfor attempts to clear up the phylogenetical connectionsof the family and attracted many researchworkers to the study of this group.Nevertheless, many aspects remain in the nomenclature,the taxonomy and the phylogeny of the familyThiolliericrinidae. The abundant new material at theauthor’s disposal allows to propose a solution of theseproblems.2 — LOCALITIES AND MATERIALSRemains of the Thiolliericrinidae were found insome regions of the Crimea (fig. 1). The Belbek Val-'/ley is the most important among them according tothe quantity of found specimens and to the diversityof forms (table 1). In that locality, crinoids under discussionwere found in the Upper Berriasian coralalgalor coral-sponge bioherms. Three types of themcan be distinguished :- 1 : the « yet-formed » bioherms. They are smalllenses (not more than one metre thick and up to 10 mlong) enclosed into the strata of the microphytolithicor bioclastic stratified limestones. The lenses are builtwith skeletons of colonial and solitary corals, calcareousalgae and sponges. Oyster shells (Lopha,Exogyra and others), brachiopod shells, echinoid spines(Diplocidaris) are found in a great quantity.
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Page 5 and 6: — 628 —Name of s p ecies L o ca
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thiolliericrinid crinoids from the lower cretaceous of crimea

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