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Background: The superorder Forcipulatacea is a major clade of sea stars with approximately 400 extant species across three orders (Forcipulatida, Brisingida, Zorocallida). Over the past century, the systematics of Forcipulatacea have undergone multiple revisions by various authors, with some considering numerous families such as Asteriidae, Zoroasteridae, Pedicellasteridae, Stichasteridae, Heliasteridae, Labidiasteridae, and Neomorphasteridae, while others recognized only two families (i.e., Asteriidae and Zoroasteridae). Recent molecular analyses have shown the artificial nature of some of these groupings. Notably, four well-supported clades (Zorocallida, Brisingida, Stichasteridae, and Asteriidae) emerged from a synthesis of morphological and molecular evidence. The majority of extinct forcipulatacean species have been placed in modern families. However, many of these fossil species are in need of revision, especially those species placed within the Asteriidae, the largest of all forcipulatacean families. Methods: In light of recent advancements in forcipulatacean systematics, we comprehensively reassess six well-preserved Jurassic forcipulatacean taxa, including the earliest crown-group members from the Hettangian (∼201.4 Ma), and also describe two new Jurassic genera, Forbesasterias gen. nov. and Marbleaster gen. nov. We assembled the largest and most comprehensive phylogenetic matrix for this group, sampling 42 fossil and extant forcipulatacean species for 120 morphological characters. To infer phylogenetic relationships and construct an evolutionary timeline for the diversification of major clades, we conducted a Bayesian tip-dating analysis incorporating the fossilized birth-death process. A total of 13 fossil species were sampled in our analysis, including six taxonomically revaluated herein, two recently reappraised species from the Jurassic, and five additional species from the Cretaceous and Miocene. Results: Contrary to prior assumptions, our results indicate that none of the Jurassic taxa investigated belong to Asteriidae or any other modern families, and instead represent stem-forcipulatids. Furthermore, our phylogenetic results suggest that Asteriidae likely originated during the late Cretaceous. Our findings highlight a greater early diversity within the Forcipulatacea than previously presumed, challenging existing perceptions of the evolutionary history of this significant clade of marine invertebrates. [ABSTRACT FROM AUTHOR]

The family Zoroasteridae is a clade of extant sea stars found exclusively in deep marine environments (i.e. bathyal environments deeper than 200 m). In the fossil record, seven species have been compared and/or assigned to the Zoroasteridae, on a time span ranging from the Middle Jurassic to the Miocene. This study describes a new taxon, Viridisaster guerangeri gen. et sp. nov., from the Cenomanian of Le Mans (Sarthe, France) and reappraises two Mesozoic species, the Jurassic Terminaster cancriformis and the Early Cretaceous Protothyraster priscus. To test the relationships of the putative fossil zoroasterids with modern taxa, a phylogenetic analysis was performed combining six of the best-known fossil species and 29 forcipulatacean species, including four Zoroasteridae. Many of the characters that define the extant Zoroasteridae do not appear in the fossil record before the Cenozoic. The family name is maintained for the crown group only. The family Terminasteridae, that accounted for the genera Terminaster and Alkaidia, is found paraphyletic and is rejected here. The order Zorocallida, initially erected for the family Zoroasteridae only, is redefined as the sister clade to the Forcipulatida that includes the crown-group Zoroasteridae and its stem relatives. Mesozoic Zorocallida are small in size compared to the Cenozoic Zorocallida, and they express morphological characters that are typical of juvenile Zoroasteridae; thus, the emergence of modern forms is likely associated with peramorphic evolution. The palaeoecology of the Zoroasteridae and their restriction to deep-sea environments after the Eocene is discussed. [ABSTRACT FROM AUTHOR]

Eight coleoid genera have so far been described from the Callovian‐aged La Voulte‐sur‐Rhône Lagerstätte (c. 165 Ma; Ardèche, France), a locality noted for its unique three‐dimensional preservation of soft tissues. Here, we used high resolution x‐ray‐based imaging methods, in conjunction with reflectance transformation imaging, to study the soft tissues of a previously undescribed coleoid from the La Voulte‐sur‐Rhône locality. This analysis identified both an ink sac and internal light organs, a combination of defence mechanisms present in the Recent, although not previously described from the coleoid fossil record, as well as the presence of Octobrachia‐type arm musculature and Vampyroteuthis‐like sucker attachments. The morphology of the gladius could not be attributed to any known coleoids and therefore justified the assignment of this single specimen to a new taxon: Vampyrofugiens atramentum. The addition of this new vampyromorph species not only increases the coleoid diversity known from the site, but also broadens the morphological variation observed in the co‐occurring coleoid taxa. These findings suggest that there was a high diversity of cephalopods occupying differentiated communities during the Middle Jurassic. [ABSTRACT FROM AUTHOR]

The vineyard of Bandol is confronted with an important land pressure in a very urbanized and very touristic area. The new parcels that appear at the northern edge of the vineyard must comply with a certain number of rules in order to maintain the quality and typicality of the wines.

The phylogenetic history of rudist bivalves is reviewed using a cladistic analysis based on 41 morphological shell characters and a new topology is proposed. A novel approach to rudist comparative anatomy has enabled the mapping of homologous zones. We highlight that 'pallial canals' can be homologous to four specific cavities that have merged during rudist evolution. The characters of the myophores and muscle insertions have also been reappraised using a hierarchical scheme. We formalize, for the first time, the complex diversification of rudist myophores by constructing tree-like characters that can contain up to six informative states for each of the four myophores. All characters have been coded as independent features. This has enabled the identification of different evolutionary rates of change between left and right valves and allows the recognition of the various morphoanatomic responses of one valve to the structural changes of the other. All characters have been coded in hierarchies and analysed in three-taxon analysis. Taxonomic sampling composed of two species per family allows an exhaustive monophyly test of all families of the suborder Hippuritidina. Only the families Polyconitidae, Plagioptychidae, Radiolitidae and Hippuritidae are found to be monophyletic. The two superfamilies are both found to be polyphyletic. The Hippuritidae is found to be the sister group of the Radiolitidae. Pachytraga is found as the sister group of all the rudists with pallial canals except Sellaea. Two evolutionary radiations in rudists are dated, using the cladistic concept of temporal hierarchy, to the Hauterivian + and the Albian+. [ABSTRACT FROM AUTHOR]

Forcipulatacea is one of the three major groups of extant sea stars (Asteroidea: Echinodermata), composed of 400 extant species, but only known from fewer than 25 fossil species. Despite unequivocal members being recognized in the early Jurassic, the evolutionary history of this group is still the subject of debate. Thus, the identification of any new fossil representatives is significant. We here reappraise Ophidiaster davidsoni de Loriol and Pellat 1874 from the Tithonian of Boulogne, France, which was assigned to another major extant group, the Valvatacea, and reassign it within a new forcipulatacean genus, Psammaster gen. nov. Psammaster davidsoni gen. nov. possess key Forcipulatacea synapomorphies including compressed ambulacrals and adambulacrals and typical organization of the body wall and arm ossicles. A phylogenetic analysis including Psammaster davidsoni gen. nov. does not place it within any existing forcipulatacean family. Instead, Psammaster davidsoni gen. nov. exhibits a mix of plesiomorphic and derived characters and is resolved as a sister clade to a large group including the Asteriidae, Stichasteridae, and Heliasteridae. Removal of this species from the Ophidiasteridae means their oldest fossil representative now dates from the Santonian, Upper Cretaceous. [ABSTRACT FROM AUTHOR]

A new phylogenetic analysis of the superorder Forcipulatacea is presented. Forcipulatacea is one of the three major groups of sea stars (Asteroidea: Echinodermata), composed of 400 extant species. The sampled taxa are thought to represent the morphological diversity of the group. Twenty-nine forcipulate taxa were sampled belonging to Asteriidae, Stichasteridae, Heliasteridae, Pedicellasteridae, Zoroasteridae and Brisingida. Specimens were dissected with bleach. Detailed description of the skeleton and the anatomy of the ossicles were investigated using scanning electron microscopy. Comparative anatomy allowed the scoring of 115 phylogenetically informative characters. The consensus tree resulting from the analysis recovers Asteriidae, Stichasteridae, Zoroasteridae and Brisingida as monophyletic. All types of morphological features contribute to tree resolution and may be appropriate for taxon diagnosis. The synapomorphies supporting different clades are described and discussed. Brisingida and Zoroasteridae are the best-supported clades. The potentially challenging position of Brisingida in the tree may be explained by homoplastic changes, but also by the presence of numerous non-applicable characters. [ABSTRACT FROM AUTHOR]

The complete ontogenetic development of an asteroid skeleton has never been described formally for any species. Here, we describe in detail the post‐metamorphic ontogeny of Zoroaster fulgens Thomson, 1873. The major novelty of our work is the description of patterns of plate addition, the ontogeny of the internal ossicles, as well as the variability of ossicles according to their position along series. Seven specimens collected in the Rockall Basin (North Atlantic) were dissected with bleach and their anatomy was documented using a scanning electron microscope. The external anatomy was additionally observed on more than 30 specimens. We found that the overall structure of the skeleton does not change much between juveniles and adults, but the shape of individual ossicle changes during growth. Allometric scaling was particularly visible on the orals, ambulacrals and adambulacrals. The shape of an ossicle is more dependent of its position along the arm series than of its individual size. Many morphological features differentiate progressively during ontogeny, while others are expressed consistently among specimens. The study of this ontogenetic series allows discussing the homology between the structures present on the ossicles of Z. fulgens in particular and other forcipulatacean sea stars in general (i.e. muscles insertions and articulation areas). The new data obtained in this study provide a comprehensive framework of the anatomy and ontogeny of Z. fulgens that will help resolve taxonomic and phylogenetic controversies in the future. [ABSTRACT FROM AUTHOR]

We describe Superstesaster promissor gen. et sp. nov., a starfish from the Smithian (Early Triassic) of Utah (USA) that fills a major gap in the fossil record of the Asteroidea. The post-Palaeozoic crown group Asteroidea are distinct from any of the diverse Palaeozoic forms. However, current understanding of the Palaeozoic-Mesozoic transition is blurred by a large gap in the fossil record between the Early Permian and the Middle Triassic. Building on the newly described taxon, a phylogenetic analysis investigates the relationships between Palaeozoic and Mesozoic Asteroidea. Including 30 species and 70 morphological characters, it is the most comprehensive phylogeny produced for fossil starfishes so far. Relationships among Palaeozoic forms remain poorly resolved, but their position in the tree is grossly consistent with stratigraphy. The tree topology implies the appearance of a wide range of morphologies during the Ordovician, a bottleneck during the end-Devonian events, and a second diversification during the Carboniferous, before a diversity decline at the end of the Permian. Superstesaster promissor nests above Palaeozoic taxa and appears as the sister group to the post-Palaeozoic Asteroidea. It represents the first record of a member of the stem group in the Mesozoic, and it likely reflects the ancestral morphology of the crown group. S. promissor shares with the crown group typical ambulacral and adambulacral plate shape and articulation. Phylogenetic relationships within the crown group remain poorly resolved, although three clades are consistent with molecular and morphological phylogenies available for extant forms: Valvatacea (Comptoniaster, Pentasteria, Advenaster, Noviaster), Forcipulatacea (Germanasterias, Argoviaster) and Velatida (Tropidaster, Protremaster). A Triassic and Jurassic radiation of the crown group is confirmed. Most Triassic and Jurassic forms do not share all synapomorphies with extant clades and usually represent separate clades or stem members of modern clades rather than true members of modern families. [ABSTRACT FROM AUTHOR]

A mass occurrence, numbering tens of thousands of individuals in a single lens, belonging to a single species of asteroid, is described from the late Maastrichtian (Late Cetaceous) of Morocco. The lens of partially silicified asteroidal limestone is made up largely of fully articulated specimens of similar size and probably represents the mass mortality of a single recruitment. By comparison with mass strandings of the present-day species Asterias rubens (Linnaeus), it can be inferred that a feeding swarm of individuals was swept into a submarine channel by either a storm or an exceptionally strong tidal current, and permanently buried. The genus and species are herein described as Cretasterias reticulatus gen. et sp. nov. The exceptional preservation of the material enables the identification of wreath organs (clusters of crossed pedicellariae set in a dermal pad around spines) for the first time in the fossil record. Comparison between extant Asteriidae, putative fossil asteriids and C. reticulatus provides ambiguous evidence of its affinities; it appears to display a combination of plesiomorphic and derived characters. It is shown that all Mesozoic forcipulatid asteroids described so far share a very simple arm construction (single row of adradial ossicles) unknown in adult extant Forcipulatida. [ABSTRACT FROM AUTHOR]

The National Paleontology Collection is the most important paleontological collection in Mexico due to the relevance of its specimens, curation, and service to the scientific community. This work is based on the revision and the taxonomic update of the echinoderms deposited into the Collection of Types of the National Collection of Paleontology (CNP). We obtained the echinoderm database of the National Paleontology Collection, being collated with the specimens and their labels. All these specimens are included with their catalog number, taxonomy, localities, and geological age. The nomenclature and taxonomy of each species were revised based on the most recent references. The geological information (nomenclature, age, or unit) was derived from the original publications, updated, and complimented with more recently published data, in congruence with the Stratigraphic Lexicon of Mexico. The CNP houses a total of 385 records classified in 107 species: 19 Crinoidea, 1 Asteroidea, 1 Ophiuroidea, 84 Echinoidea, and 2 Holothuroidea; 27 changes in their taxonomy were done. The echinoderm records come from 69 localities, 52 assigned to 31 formations/units across the country, and 17 not assigned yet. The Cretaceous is the best represented period with 14 formations/units and 6 localities. San Juan Raya (Puebla) is the most diverse formation with 12 species of Echinoidea; The Tlayúa formation (Puebla), due to its excellent quality o preservation, is the only one with fossil ophiuroid and holothuroid species reported in Mexico. This paper is the beginning of a series of publications focused on the analysis of the systematics, paleodiversity, past ecosystem structures, and paleobiogeography of the Mexican fossil echinoderms and applying novel approaches. • The National Collection of Paleontology, Mexico, houses 107 species of echinoderms. • The Class Echinoidea is the most diverse, with 84 fossil species. • Echinoderm are reported from 31 distinct geological units or Formations from Mexico. • Mexico has an important Cretaceous echinoderm record. [ABSTRACT FROM AUTHOR]

Distinct faunal aggregates are described from the Middle Jurassic (uppermost Bajocian/lowermost Bathonian and Middle Bathonian) clay deposits of Częstochowa area, south-central Poland. These aggregates are composed of molluscs (scaphopods, gastropods, bivalves, ammonites and belemnites), articulate brachiopods and echinoderms (asteroids, crinoids and echinoids). A large percentage of the fossils, especially bivalves, are fragmented, but some fossils are complete. Although most of the fossils are crushed and fragmented, they are still identifiable to at least the genus level. Thorough statistical analysis of taphonomic features indicates that the preservation of asteroid marginal plates is distinct from the ossicles derived from the host clays. The high frequency of bite marks and the good state of preservation suggest that the accumulations are the products of predation activities and most probably are the effect of regurgitation. Taking into account the rich and diverse fauna, the predator was a bottom-feeding generalist. Possible predators include palaeospinacid sharks, a tooth of which was collected from the same bedding surface, but not associated with regurgitated remains. Although the bite marks on the asteroid ossicles point to sharks as potential producers of regurgitates, other vertebrates, like durophagous pycnodontiform fish, cannot be excluded. [ABSTRACT FROM AUTHOR]

This paper describes the evolution of an extensional basin in regard to the nature and sequence stratigraphic arrangement of its carbonate deposits. The purpose of this study is to evaluate the respective effects of tectonism, eustasy, climate and oceanography on a carbonate sedimentary record. The case study is the early to mid-Jurassic age carbonate succession of the Southern Provence Sub-basin (SE France), located within the southern part of the extensional Western European Tethyan Margin. This work is based on sedimentologic, biostratigraphic (using ammonites and brachiopods) and sequence stratigraphic analysis of the carbonate facies of the Cherty Reddish Limestone Formation (late Sinemurian to earliest Bajocian). These strata were deposited in shoreface to lower offshore depositional environments. The succession of the various environments together with the recognition of key stratigraphic surfaces allow us to define four second-order depositional sequences; of late Sinemurian to earliest Pliensbachian, early Pliensbachian to late Pliensbachian, earliest Toarcian to middle Aalenian and late Aalenian to early Bathonian ages. The architecture of the depositional sequences (thickness and facies variations within the systems tracts, wedge-shaped geometries) reflects a strong tectonic control. The sub-basin was structured by extensional faults (oriented approximately 070–090/250–270). Sea-level variations, fluctuations in carbonate production and preservation, and environmental changes were also significant controlling factors of the carbonate deposition. The interplay of the tectonic control with the other factors resulted in five main phases in the sedimentary evolution of the sub-basin: (1) dominant tectonic control during the initial rifting stage (late Sinemurian to early Pliensbachian); (2) increasing extensional tectonics (mid-Pliensbachian); (3) global climato-eustatic sea-level fall (latest Pliensbachian) and global climato-eustatic sea-level rise plus hypoxia/anoxia (early Toarcian); (4) relative sea-level fall linked to tectonic uplift related to the ‘Mid-Cimmerian phase’ (mid-Aalenian) and (5) oceanographic events (upwelling) and reduction in carbonate production (hypoxia/anoxia) plus tectonic downwarping (late Aalenian/earliest Bajocian). [ABSTRACT FROM AUTHOR]

A phylogenetic analysis of 36 species provides a test for the taxonomy and the history of Early Cretaceous spatangoids. Most taxonomic units from genera to suborders are consistent with the proposed phylogenetic framework. We retain Hemiasterina, Micrasterina, Hemiasteridae, Schizasteridae, Hemiaster, Heteraster, Mecaster, and Periaster as original monophyletic groups. However, all of these clades originate without the classical apomorphies normally ascribed to them. We suggest a revision of their diagnoses and of the generic attributions of basal species. Some ill-defined, ‘primitive’, and paraphyletic taxa are recognised: Toxaster, Epiaster, Palhemiaster, and Toxasteridae. Even if they do not have phylogenetic meaning, they are retained here, pending a more complete revision. [ABSTRACT FROM AUTHOR]

Abstract: Evolution and adaptative radiations in echinoids. Echinoids (sea urchins) originated in the Early Paleozoic and, after a first period of diversification during that era, participated in an intense evolutionary radiation during the Mesozoic and Cenozoic. In the context of a reconsideration of homologies for echinoderm body regions, we present several major aspects of echinoid evolution: the origins of irregularity and bilateral symmetry; a model of radiation exemplified by the spatangoids; the diversification of modes of echinoid reproduction. These examples allow us to understand the extent of and capacity for innovation demonstrated by sea urchins during their post-Paleozoic radiation. [Copyright &y& Elsevier]