scholarly journals A new small-bodied ornithopod (Dinosauria, Ornithischia) from a deep, high-energy Early Cretaceous river of the Australian–Antarctic rift system

PeerJ ◽  
2018 ◽  
Vol 5 ◽  
pp. e4113 ◽  
Author(s):  
Matthew C. Herne ◽  
Alan M. Tait ◽  
Vera Weisbecker ◽  
Michael Hall ◽  
Jay P. Nair ◽  
...  

A new small-bodied ornithopod dinosaur,Diluvicursor pickeringi, gen. et sp. nov., is named from the lower Albian of the Eumeralla Formation in southeastern Australia and helps shed new light on the anatomy and diversity of Gondwanan ornithopods. Comprising an almost complete tail and partial lower right hindlimb, the holotype (NMV P221080) was deposited as a carcass or body-part in a log-filled scour near the base of a deep, high-energy river that incised a faunally rich, substantially forested riverine floodplain within the Australian–Antarctic rift graben. The deposit is termed the ‘Eric the Red West Sandstone.’ The holotype, interpreted as an older juvenile ∼1.2 m in total length, appears to have endured antemortem trauma to the pes. A referred, isolated posterior caudal vertebra (NMV P229456) from the holotype locality, suggestsD. pickeringigrew to at least 2.3 m in length.D. pickeringiis characterised by 10 potential autapomorphies, among which dorsoventrally low neural arches and transversely broad caudal ribs on the anterior-most caudal vertebrae are a visually defining combination of features. These features suggestD. pickeringihad robust anterior caudal musculature and strong locomotor abilities. Another isolated anterior caudal vertebra (NMV P228342) from the same deposit, suggests that the fossil assemblage hosts at least two ornithopod taxa.D. pickeringiand two stratigraphically younger, indeterminate Eumeralla Formation ornithopods from Dinosaur Cove, NMV P185992/P185993 and NMV P186047, are closely related. However, the tail ofD. pickeringiis far shorter than that of NMV P185992/P185993 and its pes more robust than that of NMV P186047. Preliminary cladistic analysis, utilising three existing datasets, failed to resolveD. pickeringibeyond a large polytomy of Ornithopoda. However, qualitative assessment of shared anatomical features suggest that the Eumeralla Formation ornithopods, South AmericanAnabisetia saldiviaiandGasparinisaura cincosaltensis, Afro-Laurasian dryosaurids and possibly AntarcticMorrosaurus antarcticusshare a close phylogenetic progenitor. Future phylogenetic analysis with improved data on Australian ornithopods will help to test these suggested affinities.

Zootaxa ◽  
2012 ◽  
Vol 3166 (1) ◽  
pp. 1 ◽  
Author(s):  
JULIA B. DESOJO ◽  
MARTÍN D. EZCURRA ◽  
EDIO E. KISCHLAT

We describe the new aetosaur Aetobarbakinoides brasiliensis gen. et sp. nov. from the early Late Triassic (late Carnian-early Norian) Brazilian Santa Maria Formation. The holotype is composed of a partial postcranium including several cer-vical and dorsal vertebrae and ribs, one anterior caudal vertebra, right scapula, right humerus, right tibia, partial right pes,and anterior and mid-dorsal paramedian osteoderms. Aetobarbakinoides is differentiated from other aetosaurs by the pres-ence of cervical vertebrae with widely laterally extended prezygapophyses, mid-cervical vertebrae with anterior articularfacet width more than 1.2 times wider than the posterior one, anterior caudal vertebrae with extremely anteroposteriorlyshort prezygapophyses, elongated humerus and tibia in relation to the axial skeleton, and paramedian osteoderms with aweakly raised anterior bar. A cladistic analysis recovered the new species as more derived than the South American generaAetosauroides (late Carnian-early Norian) and Neoaetosauroides (late Norian-Rhaetian), and it is nested as the sister-tax-on of an unnamed clade, composed of Typothoracisinae and Desmatosuchinae, due to the absence of a ventral keel in thecervical vertebrae. Aetobarbakinoides presents a skeletal anatomy previously unknown among South American aetosaurs,with the combination of presacral vertebrae with hyposphene, anteroposteriorly short and unkeeled cervical vertebrae,gracile limbs, and paramedian osteoderms with a weakly raised anterior bar. Aetobarbakinoides is among the oldest knownaetosaurs together with Aetosauroides from Argentina and Brazil and Stagonolepis robertsoni from Scotland, indicatinga widely distributed early record for the group. In addition, the recognition of a suite of derived features in Aetobarbaki-noides, which is one of the oldest known aetosaurs, is in agreement with an older origin for the group, as it is expected by the extensive ghost lineages at the base of the main pseudosuchian clades.


2008 ◽  
Vol 39 (4) ◽  
pp. 381-406 ◽  
Author(s):  
Mariana Chani-Posse de Maus

AbstractThe genus Endeius Coiffait & Sáiz, 1968 (Staphylininae: Staphylinini), distributed from Chile and Argentina through Juan Fernández Is. and Galapagos Is., is revised using characters of external morphology and male and female genitalia. Endeius comprises seven valid species: E. punctipennis (Solier), E. nitidipennis (Solier), E. subpunctipennis Coiffait & Sáiz, E. loensis Coiffait & Sáiz, E. franzi Sáiz, E. lugubris Sáiz and E. ovaliceps Coiffait. Belonuchus multipunctatus (Coiffait), comb. nov., is excluded from Endeius. An identification key to all species of the genus is provided. Monophyly of Endeius, as considered in the present study, is supported by one synapomorphy from the external morphology. Within the genus, the best supported subgroup consists of E. punctipennis (Solier), E. subpunctipennis Coiffait & Sáiz, E. loensis Coiffait & Sáiz and E. ovaliceps Coiffait.


2001 ◽  
Vol 15 (3) ◽  
pp. 353 ◽  
Author(s):  
Brian E. Heterick

The Australian ants of the genus Monomorium are revised. Fifty-nine species are recognised. Of these, 41 are described as new: Monomorium aithoderum, M. albipes, M. anderseni, M. anthracinum, M. arenarium, M. bifidum, M. bihamatum, M. brachythrix, M. burchera, M. capito, M. carinatum, M. castaneum, M. crinitum, M. decuria, M. disetigerum, M. draculai, M. durokoppinense, M. elegantulum, M. eremophilum, M. euryodon, M. flavonigrum, M. lacunosum, M. legulus, M. longinode, M. macarthuri, M. majeri, M. megalops, M. micula, M. nanum, M. nightcapense, M. nigriceps, M. parantarcticum, M. petiolatum, M. pubescens, M. ravenshoense, M. rufonigrum, M. shattucki, M. silaceum, M. stictonotum, M. striatifrons, and M. xantheklemma. Thirteen species pass into synonymy: M. armstrongi with M. whitei, M. broomense and M. ilia with M. laeve, M. donisthorpeiand M. fraterculus with M. fieldi, M. flavipes and M. insularis with M. leae, M. foreli with M. sordidum, M. howense with M. tambourinense, M. macareaveyi with M. bicorne, M. sanguinolentum with M. rubriceps, M. subapterum with M. rothsteini, and M. turneri withM. gilberti. Sixteen infraspecific forms are also synonymised: M. kilianii obscurelluminto M. kilianii, M. laeve nigriusand M. laeve fraterculus into M. fieldi, M. ilia lamingtonensisinto M. laeve, M. rothsteini humilior, M. rothsteini leda, M. rothsteini doddi and M. subapterum bogischi into M. rothsteini, M. rothsteini squamigena, M. rothsteini tostum and M. sordidum nigriventris into M. sordidum, M. fraterculus barretti and M. sydneyense nigella into M. sydneyense, M. gilberti mediorubra into M. gilberti, and M. rubriceps cinctumand M. rubriceps rubrum into M. rubriceps. Seventeen species and one subspecies are unchanged. Monomorium kiliani reverts to M. kilianii, M. kilianii tambourinenseis raised to species status, M. occidaneus is here treated as a species inquirenda, and M. flavigaster is removed from the genus Monomorium. Since the generic status of the latter taxon is uncertain, M. flavigaster is here regarded as incertae sedis. The supposedly extralimitalMonomorium talpa is synonymised under Monomorium australicum. At a higher taxonomic level the South American genus Antichthonidris is synonymised under Monomorium. Seven species-groups are proposed for the Australian fauna, (the bicorne-, falcatum-, insolescens-, kilianii-, longinode-, monomorium-, and rubriceps-groups). A cladistic analysis was undertaken of species for which all castes were examined (identifiable males and/or queens were lacking for all members of the falcatum-, insolescens- and longinode-groups). In all, fifteen species of Australian Monomorium were examined (M. bicorne, M. whitei, M. striatifrons and M. rufonigrum from the bicorne-group, M. crinitumand M. kilianii from the kilianii-group, M. fieldi, M. laeve, M. rothsteini, M. sordidum and M. sydneyense from the monomorium-group, and M. centrale, M. leae, M. euryodon and M. rubriceps from the rubriceps-group), together with Monomorium antarcticum(from New Zealand) and the Neotropical Antichthonidris denticulatus. The taxon used for the outgroup was the Neotropical ant Megalomyrmex modestus. Using the PAUP program, 37 characters for worker, queen and male castes were analysed. The clade incorporating the tiny generalists (M. fieldi, M. laeve, M. sordidum, and M. sydneyense), together with M. rothsteini, was found to be the clade most strongly supported as a monophyletic grouping. In this analysis M. euryodon was the sister taxon to the above clade. These ants were shown on this analysis to share a common ancestor with the other members of the rubriceps-group, with M. antarcticum and A. denticulatus, and with thekilianii-group. The relationships between these latter four sets of species were left unresolved, except that M. crinitum was shown to be the sister taxon to M. kilianii. The large, arid zone species in thebicorne-group were also shown as ancestral to the other Australian Monomorium. A key is provided to enable researchers to identify the workers of all Australian Monomorium, as well as extralimital species established in Australia.


2019 ◽  
Vol 93 (3) ◽  
pp. 543-584 ◽  
Author(s):  
Matthew C. Herne ◽  
Jay P. Nair ◽  
Alistair R. Evans ◽  
Alan M. Tait

AbstractThe Flat Rocks locality in the Wonthaggi Formation (Strzelecki Group) of the Gippsland Basin, southeastern Australia, hosts fossils of a late Barremian vertebrate fauna that inhabited the ancient rift between Australia and Antarctica. Known from its dentary,Qantassaurus intrepidusRich and Vickers-Rich, 1999 has been the only dinosaur named from this locality. However, the plethora of vertebrate fossils collected from Flat Rocks suggests that further dinosaurs await discovery. From this locality, we name a new small-bodied ornithopod,Galleonosaurus dorisaen. gen. n. sp. from craniodental remains. Five ornithopodan genera are now named from Victoria.Galleonosaurus dorisaen. gen. n. sp. is known from five maxillae, from which the first description of jaw growth in an Australian dinosaur is provided. The holotype ofGalleonosaurus dorisaen. gen. n. sp. is the most complete dinosaur maxilla known from Victoria. Micro-CT imagery of the holotype reveals the complex internal anatomy of the neurovascular tract and antorbital fossa. We confirm thatQ. intrepidusis uniquely characterized by a deep foreshortened dentary. Two dentaries originally referred toQ. intrepidusare reassigned toQ.?intrepidusand a further maxilla is referred to cf.Atlascopcosaurus loadsiRich and Rich, 1989. A further ornithopod dentary morphotype is identified, more elongate than those ofQ. intrepidusandQ.?intrepidusand with three more tooth positions. This dentary might pertain toGalleonosaurus dorisaen. gen. n. sp. Phylogenetic analysis recovered Cretaceous Victorian and Argentinian nonstyracosternan ornithopods within the exclusively Gondwanan clade Elasmaria. However, the large-bodied taxonMuttaburrasaurus langdoniBartholomai and Molnar, 1981 is hypothesised as a basal iguanodontian with closer affinities to dryomorphans than to rhabdodontids.UUID:http://zoobank.org/4af87bb4-b687-42f3-9622-aa806a6b4116


Zootaxa ◽  
2008 ◽  
Vol 1727 (1) ◽  
pp. 1 ◽  
Author(s):  
CAROLINA NIETO ◽  
BARTON RICHARD

Three new species of Cloeodes are described from Argentina (C. barituensis, C. espinillo and C. opacus), based on nymphs and from adults for the first two species. Two species, C. stelzneri and C. nocturnus, are proposed as nomen dubia. The only other species from Argentina, C. penai, is revised. The validity of the monotypic genus Bernerius is analyzed. A cladistic analysis including five species of the genus Cloeodes and Bernerius is presented and the synonymy of the latter is confirmed. A key for South American species of Cloeodes is presented.


2017 ◽  
Vol 284 (1847) ◽  
pp. 20161902 ◽  
Author(s):  
David G. DeMar ◽  
Jack L. Conrad ◽  
Jason J. Head ◽  
David J. Varricchio ◽  
Gregory P. Wilson

Iguanomorpha (stem + crown Iguania) is a diverse squamate clade with members that predominate many modern American lizard ecosystems. However, the temporal and palaeobiogeographic origins of its constituent crown clades (e.g. Pleurodonta (basilisks, iguanas, and their relatives)) are poorly constrained, mainly due to a meagre Mesozoic-age fossil record. Here, we report on two nearly complete skeletons from the Late Cretaceous (Campanian) of North America that represent a new and relatively large-bodied and possibly herbivorous iguanomorph that inhabited a semi-arid environment. The new taxon exhibits a mosaic of anatomical features traditionally used in diagnosing Iguania and non-iguanian squamates (i.e. Scleroglossa; e.g. parietal foramen at the frontoparietal suture, astragalocalcaneal notch in the tibia, respectively). Our cladistic analysis of Squamata revealed a phylogenetic link between Campanian-age North American and East Asian stem iguanomorphs (i.e. the new taxon + Temujiniidae). These results and our evaluation of the squamate fossil record suggest that crown pleurodontans were restricted to the low-latitude Neotropics prior to their early Palaeogene first appearances in the mid-latitudes of North America.


2004 ◽  
Vol 35 (3) ◽  
pp. 307-316
Author(s):  
Mariano Donato

AbstractIn this study Parorphula is re-described based on characters from the external morphology and genitalia. This genus comprised two species: P. pallidinota and P. latipennis, that were described based mostly on characters from external morphology. The morphological analysis conducted in this study plus the support of results from a cladistic analysis showed that external morphological characters justify the creation of a new genus for P. latipennis. Therefore, the genus Neorphula is proposed and the new combination is established.


2012 ◽  
Vol 49 (2) ◽  
pp. 379-395 ◽  
Author(s):  
Angel Alejandro Ramírez-Velasco ◽  
Mouloud Benammi ◽  
Albert Prieto-Márquez ◽  
Jesús Alvarado Ortega ◽  
René Hernández-Rivera

Huehuecanauhtlus tiquichensis gen. et sp. nov. is the southernmost diagnostic basal hadrosauroid in the Americas. The holotype and referred material of this taxon came from Santonian strata in the Michoacán State, southwestern Mexico. Huehuecanauhtlus tiquichensis is diagnosed on the basis of a combination of dental, axial, and appendicular characters, including the following: at least two teeth exposed on the occlusal plane of the dentary and maxilla; seven sacral vertebrae; tall neural spines of caudal vertebrae; supraacetabular process long; and short and trapezoidal (in lateral view) postacetabular process. It differs from other hadrosauroids in having an ilium with extreme ventral deflection of the preacetabular process. Maximum parsimony cladistic analysis placed H. tiquichensis as a closely related outgroup to Hadrosauridae. The occurrence of H. tiquichensis in the Santonian of North America may be explained as a dispersal event from Asia to North America that occurred no later than the Albian or, alternatively, as a vicariant event of a most recent common ancestor widespread in both landmasses.


Zootaxa ◽  
2018 ◽  
Vol 4379 (2) ◽  
pp. 247 ◽  
Author(s):  
IVANA KARANOVIC

The Australian Candonidae ostracod fauna has few surface water representatives, despite Australia being one of the principal centers of Candonidae biodiversity. The majority of Australian species live in subterranean waters, with most genera and one tribe being endemic to the continent. Species in Australia show Tethyan and Gondwana connections, with relatives living in European and Central/South American subterranean waters. I describe Hancockcandonopsis gen. nov. from boreholes in the alluvial aquifers of the Peel River and Hunter Valley, which at present contains five species, of which three are named, H. inachos sp. nov., H. io sp. nov., and H. tamworthi sp. nov., and two are left on the open nomenclature. All species are allopatric and short range endemics. The genus belongs to the almost cosmopolitan Candonopsini tribe, and the major generic autapomorphy is a hook-shaped h3-seta on the cleaning leg. Characters on the prehensile palps and hemipenis of Hancockcandonopsis indicate a close relationship with the Queensland genus Pioneercandonopsis Karanovic, 2005 and two West Indies genera, Cubacandona Danielopol, 1978 and Caribecandona Broodbaker, 1983. A cladistic analysis, based on 32 Candonopsini species and 24 morphological characters, is used to test phylogenetic relationships among Candonopsini genera globally. Several hypotheses about the historical biogeography of this tribe are discussed. 


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