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Species-poor assemblages rich in specimens of non-marine to brackish molluscs occur in Oligocene stratigraphical successions, widely exposed in the Salento region (southernmost Apulia, Italy). Two new extinct oligohaline gastropods of the family Hydrobiidae (Caenogastropoda), Hydrobia (s.l.) galatoniana n. sp. and Hydrobia (s.l.) ionica n. sp., are described from the type-section of a richly fossiliferous transitional succession, the Late Oligocene (Chattian) Galatone Fm, cropping out in the Lecce district. This lithostratigraphical unit records foraminiferal, molluscan and ostracod assemblages indicative of alternating oligohaline to shallow water lagoonal and littoral marine conditions. At some silty levels of the investigated succession, the two new species occur in dense populations forming shell-beds in oligotypical assemblages, accompanied by smooth-shelled ostracods. An oligohaline environment is proposed for these assemblages. This paper represents a contribution to the knowledge of Oligocene hydrobiids from Italy, where their record is extremely scarce and poorly known.
KEYWORDS: Histoire de la paléontologie, Cabinets d'Histoire naturelle, Monte Bolca, paléoichtyologie, Chondrichthyes, Osteichthyes, Actinopterygii, lectotypifications
Il est généralement admis que la célèbre collection Gazola de poissons fossiles du Monte Bolca fut confisquée en mai 1797 par les commissaires qui accompagnaient l'Armée d'Italie sous les ordres du général en chef Napoléon Bonaparte. Cette collection (Gazola 1) fut ensuite déposée au Muséum national d'Histoire naturelle (MNHN) en septembre 1798. De nombreux documents inédits conservés aux Archives nationales, émanant principalement du ministère de l'Intérieur, démontrent que Gazola fut indemnisé par une rente viagère dès 1797 à laquelle vint s'ajouter une pension annuelle octroyée par le gouvernement français à partir de 1803. La saisie de la collection Gazola fut donc rétrospectivement légalisée, ce qui explique pourquoi certains commentateurs de l'époque parlèrent d'acquisition ou d'achat. Gazola, qui était propriétaire d'une partie du gisement d'où étaient tirés les fossiles, reconstitua rapidement une seconde collection. Il ne semblait pas éprouver une trop vive rancoeur envers le gouvernement français puisqu'en 1803, il offrit à Bonaparte, alors Premier Consul, une partie de cette nouvelle collection pour compléter la première qui avait été acquise par le Muséum en 1798. Le naturaliste Louis Augustin Guillaume Bosc fut mandaté pour récupérer à Vérone, durant l'été 1803, les poissons fossiles offerts par Gazola. Il dressa à cette occasion le catalogue d'une grande partie de la seconde collection Gazola. Le ministre de l'Intérieur, Jean-Antoine Chaptal, ordonna à Bosc de rapporter la totalité du cabinet d'histoire naturelle de Gazola qui voulait pourtant n'en céder qu'une partie. S'opposant à la décision de son ministre, Napoléon Bonaparte intervint en personne pour donner raison à Gazola et faire annuler la mission de Bosc. Deux années s'écoulèrent et c'est finalement Barthélémy Faujas de Saint-Fond qui se chargea de récupérer à Vérone le lot de poissons sélectionnés par Gazola pour le Muséum, fin octobre 1805, alors que la ville était le théatre des affrontements entre les armées française et autrichienne. Cette collection (Gazola 2) arriva à Paris vers le mois de juin 1806. Le catalogue de Bosc présenté ici dans son intégralité permet d'identifier, dans les collections actuelles du MNHN, quelques spécimens de cette seconde collection.
Alonissos (Iliodroma) Island is really famous to palaeobotanists because of the type locality of Glyptostrobus europaeus (Brongniart) Unger only. Since the first report of the latter holotype no palaeobotanical work has taken place in Alonissos. This is the first research of the fossiliferous locality, along with new palaeobotanical, palynological and gastropod findings, revealed after 200 years. Among the collected material, a xylitic specimen was studied and identified as Pinuxylon alonissianum Mantzouka & Sakala, sp. nov. The presence of this species points to botanical affinities with sections of Diploxylon Pines (Pinus leiophylla var. chihuahuana (Engelm.) Shaw, P. arizonica Engelm., P. arizonica var. cooperi (C.E.Blanco) Farjon, P. engelmannii Carrière and P. jeffreyi Balf.) especially from Central America (Sierra Madre Occidental and Oriental of Mexico, Arizona, California, Oregon and Sierra Nevada). This is the first research of this kind revealing as the Nearest Relative bioprovince of the studied Greek fossil pine wood Central America and not Himalayas or Asia. Moreover, a palynological study and an analysis of fossil molluscs were carried out for the first time, giving more data regarding the palaeovegetation and palaeoclimate of the area. Finally, the holotype of Glyptostrobus europaeus (Brongniart) Unger, housed in the collections of the Muséum national d'Histoire naturelle, Paris (MNHN), is found, photographed and presented for the first time.
Les rongeurs caviomorphes constituent l'un des groupes de mammifères placentaires les plus diversifiés d'Amérique du Sud. Malgré la grande diversité taxonomique actuelle et un riche registre néogène, les premières phases de l'histoire évolutive du groupe n'étaient, il y a peu, documentées que par quelques localités, majoritairement situées aux moyennes et hautes latitudes du continent sud-américain. Des recherches paléontologiques récentes menées en Amazonie péruvienne (régions de Contamana et Tarapoto) ont permis la découverte d'une vingtaine de localités éocènes et oligocènes, livrant de nombreux restes dentaires de caviomorphes. Les études systématiques effectuées sur ce matériel ont conduit à la description de nombreuses nouvelles espèces. Une analyse cladistique de grande ampleur (107 taxons terminaux; 513 caractères morphologiques), incluant ces nouvelles espèces amazoniennes, a été réalisée ici. Pour la première fois, les quatre super-familles actuelles (i.e., Cavioidea, Erethizontoidea, Chinchilloidea, et Octodontoidea) y sont largement représentées, notamment par l'ensemble des familles actuelles, elles-mêmes documentées par plusieurs représentants fossiles et/ou actuels. Cette analyse a permis la reconnaissance de caviomorphes basaux, n'appartenant à aucune de ces super-familles. Les relations de parenté étroites entre Erethizontoidea et Cavioidea d'une part, et Octodontoidea et Chinchilloidea d'autre part, comme proposé dans des phylogénies moléculaires récentes, apparaissent soutenues par les caractères morpho-anatomiques. Ce constat mène à la définition formelle des clades Erethicavioi Boivin, n. taxon (Erethizontoidea + Cavioidea + taxons éteints apparentés) et Octochinchilloi Boivin, n. taxon (Octodontoidea + Chinchilloidea + taxons éteints apparentés). Une classification synthétique des Caviomorpha est proposée. Les résultats révèlent également l'existence de trois phases de diversifications majeures au cours du Paléogène et du Miocène inférieur (radiation initiale des caviomorphes; émergence des super-familles actuelles; diversification des super-familles avec l'émergence de familles/sous-familles actuelles). Ces phases semblent coïncider avec des évènements climatiques globaux et des périodes de surrection andine intense. À la lumière de ces nouvelles données paléontologiques et des résultats phylogénétiques présentés ici, il semblerait que les régions de basses latitudes du continent sud-américain aient été le siège de la première phase de diversification des caviomorphes. L'origine géographique des super-familles reste quelque peu ambiguë, à l'exception toutefois des chinchilloïdes qui semblent avoir émergé dans les régions de basses latitudes.
Bursidae Thiele, 1925 is a moderately diverse group of extant tonnoidean gastropods with a significant fossil record. We review the fossil record of the family. We exclude some taxa from Bursidae, particularly the most ancient ones: Hanaibursa aquilana (Parona, 1909) (Aptian) and Bursa saundersiAdegoke, 1977 (Selandian). We exclude the genus Olequahia Stewart, 1926; its posterior siphonal canal is not analogous with that of Bursidae. We also discuss the possible revision of the type genus, Bursa Röding, 1798, on the basis of previously published phylogenies; the genus is not monophyletic. We create two new genera, Olssonia n. gen. (type species: Bursa chiraOlsson, 1930) and Aquitanobursa n. gen. (type species: Ranella grateloupi d'Orbigny, 1852), containing only fossil species. Lectotypes are designated for Ranella grateloupi d'Orbigny, 1852, Ranella morrisi d'Archiac & Haime, 1853 and Apollon pelouatensisCossmann & Peyrot, 1924. Based on this revision of the fossil record, we propose five fossil calibration points that can be used to date molecular phylogenetic trees of Bursidae.
KEYWORDS: Cretaceous, Lower Cenomanian, Jurassic, El Chango quarry, Dorippoidea, Majoidea, Oregoniidae, Inachoididae, Inachidae, Hymenosomatoidea, exceptional preservation, new family, new genus, new species
A small brachyuran crab, Archaeochiapasa mardoqueoi n. gen., n. sp., is reported from the lower Cenomanian (Upper Cretaceous) of the Sierra Madre Formation at El Chango Lagerstätte, Chiapas State, southeastern Mexico. Although it is decorticated and only the counterpart keeps a large part of the cuticle, the single male specimen exhibits an exceptional three-dimensional preservation that allows its description to be based not only on the dorsal carapace, both chelipeds and most walking legs, but also on remarkably conserved ventral structures: mxp3, thoracic sternum, and pleon. Archaeochiapasa mardoqueoi n. gen., n. sp. provides a morphological combination that does not conform to any previously known fossil brachyuran and furthermore to any extant family. The high number of major differential characters suggest that Archaeochiapasa n. gen. must be included in the Eubrachyura Saint Laurent, 1980. A series of apomorphies supports the erection of a new family for which we introduce the new name Archaeochiapasidae n. fam. This fortunate discovery allows us to identify one of the earliest eubrachyurans with unique features, namely a very wide thoracic sternum displaying an unexpected structure for a lower Cenomanian representative, and a depressed, rimmed area (‘flange’) along the carapace postero- and postero-lateral margin. The new family is compared to the other fossil Eubrachyura known from the Early and mid-Cretaceous, which are very scarce and often incomplete, and to the more basal heterotreme Recent clades that are presently recognised on the basis of morphological, larval, spermatozoal and genetic data, e.g. the Dorippoidea MacLeay, 1838, and to the basal families of Majoidea Samouelle, 1819 (Oregoniidae Garth, 1958, Inachoididae Dana, 1851, and Inachidae MacLeay, 1838). A challenging hypothesis based on new interpretations is that the Late Jurassic Lecythocaridae Schweitzer & Feldmann, 2009 (in Glaessneropsoidea Patrulius, 1959), only known by dorsal carapaces and formerly included in the Dromiacea De Haan, 1833, could be related, with still obscure relationships, to the same lineage as the Archaeochiapasidae n. fam. The two families actually show striking similarities, such as the overall morphology of carapace, a depressed area along the carapace posterior margin, and a bifurcate short rostrum. Therefore, we assume that, despite their Jurassic age, Lecythocaridae may well also be Eubrachyura, which brings the first “true crabs” or eubrachyurans (i.e., non-podotreme crabs) back to the Jurassic, contrary to the current opinions of paleontologists. The discovery of Archaeochiapasidae n. fam. raises a crucial question: the development of a very wide thoracic sternum in this old eubrachyuran. Is it the expression of an ancestral dispostion (plesiomorphy) or the result of an already existing evolutionary process of carcinisation (apomorphy)? And what is its phylogenetic significance?
The early Miocene mollusc faunas from the Proto-Mediterranean Sea are still poorly-known. Herein, Aquitanian gastropod assemblages from the Felli section in NW Greece are described. Two assemblages were recovered, a low-diversity coastal mudflat assemblage dominated by Granulolabium plicatum (Bruguière, 1792) and Mesohalina margaritacea (Brocchi, 1814), and a high-diversity marine assemblage dominated by Bittium larrieyense (Vignal, 1911). The marine assemblage yielded 44 species, of which three species are described as new and 23 are left in open nomenclature. A new combination is proposed for Finella perpusilla (Grateloup, 1827). The family Pyramidellidae is exceptionally represented by 15 species. 17 new occurences are reported for the Proto-Mediterranean Sea. Alvania amphitrite n. sp., Homalopoma acaste n. sp. and Pyramistomia aliakmoni n. sp. are introduced as new species.
A detailed report of the decapod crustaceans discovered in the Middle-Late Miocene outcrops of the ‘Faluns’ of Anjou-Touraine (West of France) is here presented. The Couffon's compendium (1908) is reviewed, and the systematics updated. A total of seven genera and eight species of eubrachyuran crabs, undetermined chelae, and one anomuran species, are reported. The varied decapod assemblage, dominated by Pilumnus mediterraneus (Lőrenthey, 1897), shows clear affinity with coeval decapod faunas from the Mediterranean and Paratethys realm. This fauna dwelt in a shallow warm and agitated environment of bryozoan meadows. The age of Hebertides jurassica Guinot, De Angeli & Garassino, 2007, is confirmed, and the probable provenance of the holotype is suggested. We also discuss the generic status of Scylla michelini A. Milne-Edwards, 1861 transferred herein to Necronectes A. Milne-Edwards, 1881.
This study reveals the oldest fruit enriched diet in Moschidae so far. It deals with tooth meso- and microwear of Micromeryx flourensianus Lartet, 1851 and M.? eiselei Aiglstorfer, Costeur, Mennecart & Heizmann, 2017 from the two fossil-rich middle Miocene localities, Sansan (France, 14.1 Ma) and Steinheim am Albuch (a. A., Germany, 13.5 Ma). In combination with literature data it indicates different levels of frugivory in moschids during the Miocene and suggests ecologic niche partitioning of two sympatric moschids in Steinheim a. A. The Miocene data imply a dietary shift during the evolution of the family, as feeding on fruits and/or nuts is not common in modern Moschidae. A direct comparison of the results for Sansan and Steinheim a. A. points to a slightly more abrasive diet in Steinheim a. A. and thus assumedly more arid conditions. Differences are only minor, however, and indicate that Sansan was most likely already affected as well by the middle Miocene cooling phase.
Mystacodon selenensis Lambert, Martínez-Cáceres, Bianucci, Di Celma, Salas-Gismondi, Steurbaut, Urbina & Muizon, 2017 is a toothed mysticete that represents the earliest member of the suborder in the current state of knowledge. Its holotype is a relatively complete skeleton from the upper Eocene (early Priabonian, c. 36.4 Ma) Yumaque Member of the Paracas Formation from the southern coast of Peru. The thorough description of this specimen is presented here and reveals numerous similarities with the contemporaneous basilosaurids including the retention of an innominate that originally articulated to the unpreserved hind limb. However, several characters of M. selenensis clearly relate this taxon to the mysticetes, such as the large palate with a dorsoventrally flattened rostrum, the posterior extension of the palate with an infraorbital plate of the maxilla, the shortening of the premaxillary part of the rostrum, the zygomatic process of the squamosal being closely apposed to the postorbital process of the frontal, and the humeral head being oriented more proximally than posteriorly. A parsimony analysis retrieves Mystacodon as the earliest diverging branch of the Mysticeti with no close phylogenetic relationship with Llanocetus the second oldest known mysticete (c. 34.2 Ma). The dental formula of M. selenensis is that of basilosaurids (I 3/3, C 1/1, P 4/4, M 2/3). The anterior teeth (incisors and canine) are distinctly proportionally smaller than in basilosaurids, whereas the cheek teeth are very close in relative length, but are relatively larger than in most other toothed mysticetes (except Coronodon). The large cheek teeth of Mystacodon suggest a raptorial feeding strategy, probably assisted with some degree of suction, as indicated by the large size of the palate. The anterior teeth of the holotype display a subhorizontal apical wear facet and the cheek teeth a moderately sloping wear surface, differing from the subvertical attrition facets of basilosaurids. This pattern suggests an efficient dental abrasion resulting from feeding upon abrasive food items or/and from the ingestion of sediment during prey capture, which could indicate some degree of bottom feeding. On the forelimb, the size and orientation of the acromion, the great length of the deltopectoral crest, the massiveness of the olecranon of the ulna, and the strong radial anterior process indicate powerful shoulder movements, which suggest an active use of the forelimb when foraging for food on the sea floor. The robustness of digits and the pachyosteosclerosis of ribs with pestle-like distal end corroborate such a scenario. Mystacodon selenensis represents a first step in the evolutionary history of feeding adaptations of early mysticetes; the latter are likely to have experimented an abundant set of feeding strategies and were probably very eclectic in prey choice and capture before hyperspecialized filter feeding became widespread in the suborder.
The rich vertebrate fauna of Aumelas has from decades been the subject of several partial publications, which led to assign it an age close to the MP 13 reference level in the biochronological scale of Western European mammals; but it is still partially unpublished and this paper is part of a general review of the fauna. With regard to equoid perissodactyls, five taxa have been distinguished, to be assigned to the “Pachynolophinae” to the exclusion of any Palaeotheriinae. Two leading species appear in this ensemble: Propalaeotherium sudreiRemy, Krasovec & Marandat, 2016 and Pachynolophus ruscassierensis n. sp. The three other taxa are less documented, which prevents a specific determination, Pachynolophus sp., Propalaeotherium cf. gaudryi (Lemoine, 1878) and Lophiotherium sp. All of these species display relatively archaic features as highlighted by a cladistic analysis. Such a conclusion challenges the hitherto prevailing consensus on the dating of the fauna, in the sense of an older biochronological age. This discrepancy will be discussed in a subsequent synthetic work, in conjunction with specialists of all mammal and reptile orders represented in the locality.
Sphenophyllum Brongniart, 1828 is the best-known representative of Sphenophyllales, an extinct order of small plants belonging to the Sphenophytes, the group that contains extant horsetails. Sphenophyllum is known from the Devonian to the Triassic, but most specimens are late Carboniferous in age and the anatomy of specimens present at other times is poorly known because most are preserved in compression/impressions. The Lower Carboniferous (Tournaisian) deposits of Montagne Noire in France and Thuringia in Germany contain impressions attributed to Sphenophyllum but also a few rare permineralized specimens. In this study, we describe in detail the anatomy of these specimens and compare them to other anatomically preserved Sphenophyllum species, as well as to the impressions already described in both areas. The new specimens show different developmental stages, some have a little amount of wood while the others only have primary tissues. Two specimens are branching. All are assigned to Sphenophyllum insigne Williamson. While Late Carboniferous Sphenophyllum produced a wood with a very peculiar anatomy (very large tracheids, axial system of parenchyma), that of the oldest Sphenophyllales (Devonian-Early Carboniferous) seems to be simpler and probably had different hydraulic and mechanical properties.
We report and illustrate several unpublished fossil specimens of marine arthropods, housed at the Muséum national d'Histoire naturelle in Paris (France) and coming from the Solnhofen and Nusplingen Lithographic Limestones (Late Jurassic, Germany). Notably, we describe specimens of Antrimpos undenariusSchweigert, 2001, Eryma modestiforme (Schlotheim, 1822) and Mecochirus longimanatus (Schlotheim, 1820). Mecochirus forestiSecrétan, 1968 is considered as a junior synonym of Mecochirus longimanatus. A revision of the specimens previously described is also realized. This contribution thus provides new information on the Antrimpos species from the Solnhofen Plattenkalks and gives a complete overview of the fossil marine arthropods coming from these Plattenkalks which are available at the MNHN.
The locality of Çalta has yielded one of the richest collection of fossil canids belonging to the raccoon dog genus NyctereutesTemminck, 1838. This locality is situated in central Anatolia and its age is determined as early Pliocene, c. 4 Ma. Ginsburg (1998) studied these canid remains and identified them as N. donnezani, which was previously known from some early Pliocene localities in southern France and Spain. Some later studies questioned this attribution. The present study provides a new description of all available material, housed in collections in Paris, Lyon and Ankara, and a detailed comparison of the cranial and dental characters with other known species of Nyctereutes. This study is completed by a cladistic analysis of cranial and dental characters to document the phylogenetic relationships of the Çalta raccoon dog. This analysis was done on the locality-based data, using the main occurrences of each species. Both morphological and cladistic analyses favour attribution of the Çalta raccoon dog to N. donnezani, in agreement with Ginsburg (1998). In addition, this study reveals that possible sexual dimorphism in the size and proportions of some cranial elements, such as stronger sagittal and nuchal crests, a better defined temporal line, a thicker zygomatic process of the maxillary bone, a braincase that is elongated but less round and, in particular, stronger subangular lobe in male individuals.
A large collection of fossils from the NV2K17 locality, Upper Devonian (Frasnian) Fram Formation, Ellesmere Island, Nunavut, Canada, represents at least two species of Asterolepis. The first, Asterolepis alticristata n. sp., is diagnosed by a tall midline crest that rises sharply from the tergal angle of the anterior median dorsal plate, reaches maximum height at around the position of the lateral corners, and then drops to form a low midline crest along the posterior median dorsal plate. The second species is identified as Asterolepis cf. radiata according to an ornament of radiating rows of conjoined tubercles and ridges on the available thoracic plates (anterior median dorsal, posterior median dorsal, and mixilateral). We describe additional antiarch material from the NV2K17 locality, including an anterior median dorsal plate of Bothriolepis sp. indet., and from localities throughout the Fram Formation. The antiarch occurrences in the Fram Formation conform to a possible faunal turnover from one dominated by asterolepidoids low in the formation to one dominated by bothriolepidids high in the Fram Formation. At the NV2K17 locality, in the middle of the Fram Formation, members of the two groups appear together.
Alexandre Assemat, Myriam Boivin, Laurent Marivaux, François Pujos, Aldo Benites-Palomino, Rodolfo Salas-Gismondi, Julia V. Tejada-Lara, Rafael M. Varas-Malca, Francisco Ricardo Negri, Ana Maria Ribeiro, Pierre-Olivier Antoine
Le Paléogène d'Amazonie péruvienne a livré les plus anciennes communautés de rongeurs caviomorphes d'Amérique du Sud, lesquelles sont le résultat des premières phases de diversification de ce groupe. Ce travail présente l'étude de restes dentaires inédits de rongeurs fossiles issus de deux nouvelles sections situées à proximité des villes de Juanjui et de Balsayacu (Département de San Martín, Amazonie péruvienne). Les analyses de la morphologie occlusale des dents jugales et de la microstructure de l'émail des incisives indiquent la présence de taxons basaux tels que les genres CachiyacuyAntoine, Marivaux, Croft, Billet, Ganerød, Jaramillo, Martin, Orliac, Tejada, Altamirano, Duranthon, Fanjat, Rousse & Salas Gismondi, 2012, CanaanimysAntoine, Marivaux, Croft, Billet, Ganerød, Jaramillo, Martin, Orliac, Tejada, Altamirano, Duranthon, Fanjat, Rousse & Salas Gismondi, 2012, et EoespinaFrailey & Campbell, 2004, dans les niveaux inférieurs de la série sédimentaire, auxquels succèdent des taxons plus dérivés, comme EoincamysFrailey & Campbell, 2004, dans des niveaux plus récents. Ces taxons témoignent d'une morphologie intermédiaire entre ceux documentés en Amazonie péruvienne dans les localités éocènes de Contamana (fin de l'Éocène moyen) et ceux des localités oligocènes de Tarapoto/Shapaja et Santa Rosa (?Éocène supérieur/Oligocène inférieur). Ces fossiles apportent ainsi une documentation inédite en Amazonie, en ce que les secteurs de Juanjui et de Balsayacu présentent des dépôts sédimentaires couvrant vraisemblablement la fin de l'Éocène moyen, une partie de l'Éocène supérieur et la base de l'Oligocène. Enfin, la continuité stratigraphique de la longue section de Juanjui permet de démontrer l'existence d'un hiatus temporel significatif entre les assemblages à Canaanimys-Cachiyacuy-Potamotrygon ucayalensis (Contamana, Formation Pozo; base de la section de Juanjui; Balsayacu) et ceux à Eoincamys (Santa Rosa; Tarapoto/ Shapaja; sommet de la section de Juanjui).
We describe two large amphicyonid (Amphicyonidae, Carnivora) mandibles from Moghra, Early Miocene, Egypt. One of these represents a new species of CynelosJourdan, 1862, which is in the same size range as C. macrodon (Savage, 1965) and C. ginsburgi n. comb., but exhibits a relatively longer m1 paraconid blade. The other is allocated to Amphicyon giganteus (Schinz, 1825). Based on this new material the differences between Cynelos, Amphicyon Lartet in Michelin, 1836, and AfrocyonArambourg, 1961 are clarified. We also reassign three (P4, M1, M2) of four isolated and unassociated amphicyonid teeth from Moghra, previously attributed to “Cynelos sp. nov.” to Amphicyon giganteus. These teeth represent the first record of the upper dentition of A. giganteus from Africa. Enhanced diagnoses of Cynelos and Amphicyon also permit the reallocation of some other previously described specimens to these taxa. These include: assignment of “Amphicyon sp.” and an isolated m2 previously identified as “Afrocyon burolletiArambourg, 1961” from Gebel Zelten, Libya, to the new species of Cynelos; allocation of “Ysengrinia” ginsburgi from Arrisdrift, South Africa, to Cynelos ginsburgi n. comb.; and attribution of a giant undescribed additional species from Buluk, Kenya to Cynelos sp. Other specific specimens from Gebel Zelten and Kenya, currently assigned to Afrocyon, are also transferred to either Cynelos or Amphicyon. Results from this study, combined with previous work on the Moghra carnivores, suggests that at least three and perhaps as many as four very large carnivorous genera co-existed at Moghra: Cynelos, Amphicyon, Hyainailouros Stehlin, 1907 and possibly MegistotheriumSavage, 1973. These giants represent the top predators of the Early Miocene of Africa, with Cynelos being more carnivorous, and Amphicyon, Hyainailouros and Megistotherium having more developed bone-crushing capabilities.
All Jurassic brachyuran taxa known to date are based solely upon dorsal carapaces, and only a limited number of Early and mid-Cretaceous crabs retain ventral parts. Therefore, all Jurassic taxa and many forms from the first half of the Cretaceous are carapace-based entities. All of them are considered to be “dromiaceans”, podotremes to be precise. The recent discovery of an exceptionally well-preserved male crab from the Upper Cretaceous (lower Cenomanian) of Chiapas (Mexico), Archaeochiapasa mardoqueoiGuinot, Carbot-Chanona & Vega, 2019, at first sight of a podotreme nature, has allowed a detailed description of its thoracic sternum and pleon, which revealed that it was actually a typical eubrachyuran, in need of a new family, Archaeochiapasidae Guinot, Carbot-Chanona & Vega, 2019. This has brought back to life one of my earlier ideas about the possible non-podotreme nature of certain enigmatic Late Jurassic and Cretaceous Brachyura previously placed in various “dromiacean” (i.e., podotreme) families and superfamilies. My investigations have led the me to formulate the present hypothesis that the extinct families Bucculentidae Schweitzer & Feldmann, 2009 (currently assigned to the Homolodromioidea Alcock, 1900), Lecythocaridae Schweitzer & Feldmann, 2009, Glaessneropsidae Schweitzer & Feldmann, 2009, Nodoprosopidae Schweitzer & Feldmann, 2009, and Viaiidae Artal, Van Bakel, Fraaije, Jagt & Klompmaker, 2012 (all four in Glaessneropsoidea Schweitzer & Feldmann, 2009) might, in fact (at least for some of them), be true eubrachyurans (Eubrachyura Saint Laurent, 1980). If correct, these assumptions would date the first “true crabs” as Jurassic, contrary to the currently held view that the earliest Eubrachyura (heterotremes) did not appear until the Cretaceous, and suggest that the evolutionary history of brachyurans started much earlier. This was unpredictable, at least for palaeontologists, but not so in view of a molecular estimate of decapod phylogeny that recovered the Majoidea Samouelle, 1819 as the oldest brachyuran lineage, with a divergence from other brachyurans from, at least, the Middle Triassic. The basal majoid family Oregoniidae Garth, 1958, which comprises only three extant genera, has several characters in common with Archaeochiapasidae; these leave little doubt about their close relationships. Proposals made here are inevitably based on provisional assumptions, until the characteristics of the ventral parts and pereiopods prove or refute them, either entirely or in part. Our science, which is based on the observation of specimens and then on descriptive, explanatory and, above all, predictive concepts, especially where incomplete fossil animals are concerned, should be conceived as a step forward, rather than an achievement, each of these steps being, sooner or later, replaced by a better one, or considered to be such. That is why all species and the composition of the Jurassic and Early Cretaceous genera and families will need to be checked in light of new perspectives. In contrast to the presumed eubrachyurans (see above), the Tanidromitidae Schweitzer & Feldmann, 2008 and the apparently paraphyletic family Longodromitidae Schweitzer & Feldmann, 2009 are podotremes, within the Dynomeniformia Guinot, Tavares & Castro, 2013. The status and composition of the Goniodromitinae Beurlen, 1932 (in the Dromiidae De Haan, 1833), clearly paraphyletic, are briefly revised, while some genera, such as DistefaniaChecchia-Rispoli, 1917, are tentatively assigned to the Sphaerodromiinae Guinot & Tavares, 2003. A table summarises the changes in classification implied by these new proposals and research directions. Some remarks on the new section Callichimaeroida Luque, Feldmann, Vernygora, Schweitzer, Cameron, Kerr, Vega, Duque, Strange, Palmer & Jaramillo, 2019 are provided, as well as on the the putatively callichimaeroid-like family Retrorsichelidae Feldmann, Tshudy & Thomson, 1993.
In this paper we describe Late Miocene (MN13) remains of the genus IndarctosPilgrim, 1913 from the locality of Las Casiones (Teruel, Spain). Although the phylogenetic relationships of this genus are still controversial, the most recent phylogenetic analyses, based on cranial, mandibular and dental characters, include it in Ailuropodinae, thus making the relatives of the giant panda the predominant bears in the carnivoran assemblages for most of the Late Miocene in the Iberian Peninsula. These fossils of Indarctos punjabiensis (Lydekker, 1884) represent the last population of this subfamily from the Iberian fossil record, and possibly also from Europe, making this an important advance in our knowledge of the evolutionary history of this group. We also note the replacement of Indarctos by Agriotherium A. Wagner, 1837 in Iberian faunas, between c. 6.3 and c. 6.23 Ma.
Lizard material from the early Oligocene and early and late Miocene of the Valley of Lakes, Central Mongolia is described. Besides the Oligocene fossorial squamate published elsewere, the material can be allocated to several major clades: Agamidae, Lacertidae and Anguidae (Glyptosaurinae). The presence of PseudotinosaurusAlifanov, 1991 in early and late Rupelian localities shows that this taxon has a continuous history in this area from the Eocene to the Oligocene. The same is true for the clade Glyptosaurinae, represented by isolated osteoderms in the early Oligocene locality Hsanda Gol. This might suggest that the Eocene-Oligocene transition did not have such a strong or rapid impact in East Asia, in contrast to the Grande Coupure in Europe, at least among some lizard clades. The early Oligocene (early Rupelian) lacertids from Taatsiin Gol, Hsanda Gol and Tatal Gol represent one of the oldest evidences of Asiatic dispersal of this clade. It might reflect the dispersal pathways after closure of the Turgai Strait between Europe and Asia. Some of the material closely resembles the common European Oligocene taxon Lacerta s.l. filholiAugé, 1988. In the early Miocene locality Olon Ovoony Khurem, two clades can be recognized – Lacertidae and a scincoid with a specialized dentition (family indeterminate). The clade Lacertidae forms a dominant component of the late Miocene lizard fossils in Mongolia. The material from the locality Builstyn Khudag shows differences compared to the early Miocene lacertids and represents the oldest evidence of the tribe Eremiadini in this area.
The description of new specimens of kollpaniines “condylarths” from Tiupampa (early Palaeocene of Bolivia) represents a significant addition to the knowledge of the earliest fauna of South American ungulates. Several partial mandibles and maxillae of Molinodus suarezi and Simoclaenus sylvaticus are described. The morphology of the lower premolars of Molinodus, being associated to lower molars, is established and a previous referral of an isolated p4 is rejected. A maxilla of Simoclaenus reveals the morphology of the so far unknown P1-4 of this taxon and allows a discussion on the development of the protocone in Palaeocene “condylarths”. The subvertical maxilla-premaxilla suture and the vertical implantation of the P1/p1 confirm the shortness of the snout of Simoclaenus, whereas the procumbency of the p1 of Molinodus indicates a longer rostrum. The upper molars of Molinodus confirm the presence of a tendency to duplication of the protocone, which is regarded as the incipient development of a pseudohypocone. The various patterns of formation of a hypocone (or pseudohypocone) are considered and, among other South American Native Ungulates, a protocone-derived pseudohypocone (i.e. Molinodus-like) is hypothesized in Lamegoia, Raulvaccia, and notoungulates, whereas a postcingulum-derived, hypocone is present in didolodontids and litopterns.
The new specimens confirm the conspicuous small size of the M1/m1 of Molinodus and Simoclaenus as compared to the M2/m2. Consequently, we examined the relative proportions of molars in these taxa as compared to a variety of extant and extinct euungulates. Their proportions were plotted into the ‘developmental’ morphospace based on the predictive mathematical model of Kavanagh et al. (2007) (Inhibitory Cascade Model, or IC model), which might explain a large part of the mammalian diversity in molar proportions. Based on the upper molars, the Tiupampa kollpaniines were retrieved in a separate area of the predicted morphospace with other North American “condylarths” with large M2; this departure is also consistent with previous results concerning the lower molars (large m2). These peculiar molar proportions were found distinct from many other mammals, and might represent clade-specific differences: the large size of both the upper and lower second molars relative to other molars thus possibly representing a derived character state shared by some “condylarths” and kollpaniines.
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