scholarly journals Revision of the Late Jurassic teleosaurid genus Machimosaurus (Crocodylomorpha, Thalattosuchia)

2014 ◽  
Vol 1 (2) ◽  
pp. 140222 ◽  
Author(s):  
Mark T. Young ◽  
Stéphane Hua ◽  
Lorna Steel ◽  
Davide Foffa ◽  
Stephen L. Brusatte ◽  
...  

Machimosaurus was a large-bodied genus of teleosaurid crocodylomorph, considered to have been durophagous/chelonivorous, and which frequented coastal marine/estuarine ecosystems during the Late Jurassic. Here, we revise the genus based on previously described specimens and revise the species within this genus. We conclude that there were three European Machimosaurus species and another taxon in Ethiopia. This conclusion is based on numerous lines of evidence: craniomandibular, dental and postcranial morphologies; differences in estimated total body length; geological age; geographical distribution; and hypothetical lifestyle. We re-diagnose the type species Machimosaurus hugii and limit referred specimens to only those from Upper Kimmeridgian–Lower Tithonian of Switzerland, Portugal and Spain. We also re-diagnose Machimosaurus mosae , demonstrate that it is an available name and restrict the species to the uppermost Kimmeridgian–lowermost Tithonian of northeastern France. We re-diagnose and validate the species Machimosaurus nowackianus from Harrar, Ethiopia. Finally, we establish a new species, Machimosaurus buffetauti , for the Lower Kimmeridgian specimens of France and Germany (and possibly England and Poland). We hypothesize that Machimosaurus may have been analogous to the Pliocene–Holocene genus Crocodylus in having one large-bodied taxon suited to traversing marine barriers and additional, geographically limited taxa across its range.

Zootaxa ◽  
2017 ◽  
Vol 4226 (4) ◽  
pp. 509 ◽  
Author(s):  
KRISTIN A. WALOVICH ◽  
DAVID A. EBERT ◽  
JENNY M. KEMPER

A new species of chimaerid, Hydrolagus erithacus sp. nov., is described from nine specimens collected from the southeast Atlantic and southwest Indian oceans from depths of 470–1,000 meters. This species is distinguished from all other Hydrolagus species based on the following characteristics: head bulky, relatively large, followed by stocky body; head and body height from about pectoral fin origin to pelvic fin origin similar, then tapering rapidly to filamentous tail; first dorsal fin spine height about equal to, or slightly less than first dorsal fin apex height; second dorsal fin up to 81% of total body length and uniform in height; trifurcate claspers forked for approximately 20% of total length; robust frontal tenaculum nearly uniform in width, prepelvic tenaculae with five to seven medial spines, and a uniform black coloration with robust, non-deciduous skin. Comparison of mitochondrial NADH2 gene sequences with other morphologically similar Hydrolagus species suggests that H. erithacus is a distinct species. 


PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1282 ◽  
Author(s):  
Christian Püntener ◽  
Jérémy Anquetin ◽  
Jean-Paul Billon-Bruyat

Background.The Swiss Jura Mountains are a key region for Late Jurassic eucryptodiran turtles. Already in the mid 19th century, the Solothurn Turtle Limestone (Solothurn, NW Switzerland) yielded a great amount of Kimmeridgian turtles that are traditionally referred to Plesiochelyidae, Thalassemydidae, and Eurysternidae. In the past few years, fossils of these coastal marine turtles were also abundantly discovered in the Kimmeridgian of the Porrentruy region (NW Switzerland). These findings include numerous sub-complete shells, out of which we present two new specimens ofThalassemys(Thalassemydidae) in this study.Methods.We compare the new material from Porrentruy to the type speciesTh. hugii, which is based on a well preserved specimen from the Solothurn Turtle Limestone (Solothurn, Switzerland). In order to improve our understanding of the paleogeographic distribution ofThalassemys, anatomical comparisons are extended toThalassemysremains from other European countries, notably Germany and England.Results.While one of the twoThalassemysspecimens from Porrentruy can be attributed toTh. hugii, the other specimen represents a new species,Th. bruntrutanan. sp. It differs fromTh. hugiiby several features: more elongated nuchal that strongly thickens anterolaterally; wider vertebral scales; proportionally longer plastron; broader and less inclined xiphiplastron; wider angle between scapular process and acromion process. Our results show thatTh. hugiiandTh. bruntrutanaalso occur simultaneously in the Kimmeridgian of Solothurn as well as in the Kimmeridgian of England (Kimmeridge Clay). This study is an important step towards a better understanding of the paleobiogeographic distribution of Late Jurassic turtles in Europe.


2020 ◽  
Author(s):  
Jérémy Anquetin ◽  
Charlotte André

Background. The mostly Berriasian (Early Cretaceous) Purbeck Group of southern England has produced a rich turtle fauna dominated by the freshwater paracryptodires Pleurosternon bullockii and Dorsetochelys typocardium. Each of these species is known by numerous relatively complete shells and by a single cranium. The two other turtles found in the Purbeck Group (Hylaeochelys belli, a species of uncertain affinities, and the terrestrial helochelydrid "Helochelydra" anglica) are known only from shell remains.Methods. In the present contribution, we describe a new turtle cranium from the Purbeck Group of Swanage, Dorset (southern England). We also explore the phylogenetic relationships of this new cranium and of Hylaeochelys belli in the context of a recently published global turtle matrix.Results. Before complete preparation, the new Purbeck cranium was provisionally referred to Dorsetochelys typocardium, but our analysis clearly contradicts a referral to this species in particular and to paracryptodires in general. In contrast, the new cranium shares a number of features with the Late Jurassic, coastal marine Thalassochelydia, including a posterolaterally open foramen palatinum posterius, a strong ridge on the posterior surface of the processus articularis of the quadrate, a strong posterior orientation of the processus articularis in ventral view, and a processus trochlearis oticum limited to the medial part of the otic chamber and bordered by a deep recess laterally. Our phylogenetic analysis confirms a placement of the new Purbeck cranium within the clade Thalassochelydia.Discussion. In terms of morphology, the new Purbeck cranium does not correspond to any known taxon. However, we refrain from naming a new species based on it because there is a good chance that this cranium actually belongs to the shell-based species Hylaeochelys belli (also recovered as a thalassochelydian in our phylogenetic analysis). Unfortunately, we lack any objective evidence to support this conclusion for the moment. In any case, the new Purbeck cranium confirms what others have previously suggested based on Hylaeochelys belli: thalassochelydian turtles survived the Jurassic-Cretaceous transition.


2017 ◽  
Vol 4 (10) ◽  
pp. 170499 ◽  
Author(s):  
Adam C. Pritchard ◽  
Sterling J. Nesbitt

The Triassic Period saw the first appearance of numerous amniote lineages (e.g. Lepidosauria, Archosauria, Mammalia) that defined Mesozoic ecosystems following the end Permian Mass Extinction, as well as the first major morphological diversification of crown-group reptiles. Unfortunately, much of our understanding of this event comes from the record of large-bodied reptiles (total body length > 1 m). Here we present a new species of drepanosaurid (small-bodied, chameleon-like diapsids) from the Upper Triassic Chinle Formation of New Mexico. Using reconstructions of micro-computed tomography data, we reveal the three-dimensional skull osteology of this clade for the first time. The skull presents many archaic anatomical traits unknown in Triassic crown-group reptiles (e.g. absence of bony support for the external ear), whereas other traits (e.g. toothless rostrum, anteriorly directed orbits, inflated endocranium) resemble derived avian theropods. A phylogenetic analysis of Permo-Triassic diapsids supports the hypothesis that drepanosaurs are an archaic lineage that originated in the Permian, far removed from crown-group Reptilia. The phylogenetic position of drepanosaurids indicates the presence of archaic Permian clades among Triassic small reptile assemblages and that morphological convergence produced a remarkably bird-like skull nearly 100 Myr before one is known to have emerged in Theropoda.


Zootaxa ◽  
2007 ◽  
Vol 1616 (1) ◽  
pp. 61-68 ◽  
Author(s):  
G. PRIYALAKSHMI ◽  
N. R. MENON ◽  
M. ANTONIO TODARO

During an interstitial faunal survey along the south-west coast of Kerala, India, gastrotrich fauna were found in abundance. Together with species of the genera Xenotrichula, Halichaetonotus and Tetranchyroderma, were present several undescribed thaumastodermatid gastrotrichs belonging to the buccal palp bearing genus Pseudostomella. Adults of the new species are characterized by the following traits: total body length of about 300 μ m; cuticular armature made up of medium sized pentancres covering the entire dorsolateral surface; pre-buccal, grasping palps bearing five, large papillae dorsally and 4-6 smaller papillae ventrally; adhesive apparatus made up of six anterior, 22-24 ventrolateral, two dorsolateral and six posterior adhesive tubes; caudal organ pear-shaped; frontal organ spherical. Pseudostomella cheraensis sp. nov. is the fourth taxon of the genus known from India; however, all the previous species reported hitherto from India have tetrancres instead of pentancres.


Author(s):  
Fabiano Matos Vieira ◽  
Paula Araujo Gonçalves ◽  
Sueli de Souza Lima ◽  
Bernadete Maria de Sousa ◽  
Luís Cláudio Muniz-Pereira

Abstract Cruzia lauroi sp. nov. is described from Salvator merianae (Duméril & Bibron, 1839) (Squamata; Teiidae). The new species differs from all previously described species through several morphological characteristics: number of tooth like structures per row in the inner pharynx; and presence of unpaired papillae on the anterior border of the cloacal aperture. However, Cruzia lauroi sp. nov. is closest to C. tentaculata (Rudolphi, 1819), through having similar distribution of male caudal papillae, unpaired pre-cloacal papillae and females with an pre-equatorial vulva. Cruzia lauroi sp. nov. differs from C. tentaculata regarding smaller total body length of individuals, higher number of tooth like structures per row in the pharynx, greater size of diverticulum, smaller size of spicules and a more anterior vulva than in C. tentaculata; and the males do not have caudal alae. Cruzia mazza, C. travassosia, C. mexicana and C. testudines were considered to be species inquirendae, because their descriptions need more detailed taxonomic studies.


2021 ◽  
Vol 21 (13) ◽  
pp. 265-314
Author(s):  
László Bujtor ◽  
Richárd Albrecht ◽  
Csaba Farkas ◽  
Bertalan Makó ◽  
Dávid Maróti ◽  
...  

A new collection at Zengővárkony (Mecsek Mountains, Hungary) provided a rich and diverse but poorly preserved cephalopod-dominated fossil assemblage representing the Kimmeridgian and the lower Tithonian. The material came from mixed scree, soil, and amongst roots affected by weathering processes having been exposed to the elements for a long time. The nautiloid Pseudaganides strambergensis is the first record from the Mecsek Mountains. Due to the weathering, the ammonite fauna consists of mainly fragmentary and dissolved individuals that comprises 528 specimens belonging to 34 species and 30 genera out of which 20 species and 15 genera are reported for the first time from the Mecsek Mountains. The fauna includes specimens of known taxa. No new taxa are introduced. Based on the comparison with other faunas, this assemblage most closely resembles the fauna of the Venetian Alps (Italy). Additional faunal elements include aptychi (Laevaptychus latus, Lamellaptychus murocostatus), belemnites (Hibolithes semisulcatus), and an indetermined brachiopod. The first record of Spiraserpula spirolinites, an encrusting fossil polychaete preserved on the internal mould of a Taramelliceras shell fragment indicates favourable bottom conditions for the epifauna. The presence of Aspidoceras caletanum, Gravesia aff. gigas, and Pseudowaagenia inerme indicates faunal connections with the Submediterranean Province of the Tethys, which is in line with the tectonic and palaeogeographical position of the Mecsek Zone during the Late Jurassic. The ammonite assemblage represents elements of five Tethysian ammonite zones of the Kimmeridgian and Tithonian. The lower Kimmeridgian Herbichi Zone is indicated by Streblites tenuilobatus and Praesimoceras herbichi. The upper Kimmeridgian Acanthicum Zone is indicated by Aspidoceras acanthicum, and the Cavouri Zone by Mesosimoceras cavouri and Aspidoceras caletanum. The upper Kimmeridgian Beckeri Zone is suggested by Hybonoticeras pressulum and Pseudowaagenia inerme. Whereas Gravesia aff. gigas, Lithacoceras aff. siliceum, and Malagasites? denseplicatus are faunal elements characterising the Early Tithonian Hybonotum Zone. Phylloceratid and lytoceratid specimens account only for 12% of the fauna, while the majority of the specimens belong to the Oppeliidae and Ataxioceratidae (60%).


Mammalia ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Daniela Arenas-Viveros ◽  
Pamela Sánchez-Vendizú ◽  
Alan Giraldo ◽  
Jorge Salazar-Bravo

Abstract The systematics and taxonomy of the broadly distributed bats of the genus Cynomops has changed considerably in the last few years. Among the major changes, Cynomops abrasus was split into two species of large-bodied forms (Cynomops mastivus and C. abrasus) distributed east of the Andes. However, large Colombian specimens identified as C. abrasus from the western side of the Andes had yet to be included in any revisionary work. Phylogenetic analysis performed in this study, using mtDNA sequences (Cytochrome-b), revealed that these Colombian individuals are more closely related to Cynomops greenhalli. Morphological and molecular data allowed us to recognize populations from western Colombia, western Ecuador and northwestern Peru, as members of a new species of Cynomops. Characters that allow for its differentiation from C. greenhalli include a larger forearm, paler but more uniform ventral pelage, more globular braincase, and well-developed zygomatic processes of the maxilla (almost reaching the postorbital constriction). This study serves as another example of the importance of including multiple lines of evidence in the recognition of a new species. Given its rarity and the advanced transformation of its habitat, this new species is particularly important from a conservation perspective.


Zootaxa ◽  
2020 ◽  
Vol 4766 (3) ◽  
pp. 472-484
Author(s):  
HANNAH E. SOM ◽  
L. LEE GRISMER ◽  
PERRY L. JR. WOOD ◽  
EVAN S. H. QUAH ◽  
RAFE M. BROWN ◽  
...  

Liopeltis is a genus of poorly known, infrequently sampled species of colubrid snakes in tropical Asia. We collected a specimen of Liopeltis from Pulau Tioman, Peninsular Malaysia, that superficially resembled L. philippina, a rare species that is endemic to the Palawan Pleistocene Aggregate Island Complex, western Philippines. We analyzed morphological and mitochondrial DNA sequence data from the Pulau Tioman specimen and found distinct differences to L. philippina and all other congeners. On the basis of these corroborated lines of evidence, the Pulau Tioman specimen is described as a new species, L. tiomanica sp. nov. The new species occurs in sympatry with L. tricolor on Pulau Tioman, and our description of L. tiomanica sp. nov. brings the number of endemic amphibians and reptiles on Pulau Tioman to 12. 


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