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Julia A Clarke - One of the best experts on this subject based on the ideXlab platform.
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a new stem parrot from the green river formation and the complex evolution of the grasping foot in pan Psittaciformes
Journal of Vertebrate Paleontology, 2012Co-Authors: Daniel T Ksepka, Julia A ClarkeAbstract:ABSTRACT Deposits from the Fossil Butte Member of the Green River Formation preserve exceptional fossils from one of the most diverse Paleogene avifaunas worldwide. Stem lineage parrots are well represented in this avifauna. Here we report a new species of Pan-Psittaciformes (crown clade parrots and their stem lineage relatives). The new species shares several features with extant parrots that are not present in the contemporaneous clades Halcyornithidae and Messelasturidae, including a wider pelvis, deeper trochlea cartilaginis tibialis, and larger pygostyle. Morphology of the foot suggests strong grasping ability and an arboreal ecology. Phylogenetic analysis of a combined data set of morphological and molecular sequence data resulted in limited support for a sister-group relationship between the new taxon and Quercypsittidae as well as a previously unrecognized clade including Vastanavidae, Halcyornithidae, and Messelasturidae. Regardless of whether this phylogeny or alternate hypotheses are preferred,...
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stem parrots aves halcyornithidae from the green river formation and a combined phylogeny of pan Psittaciformes
Journal of Paleontology, 2011Co-Authors: Daniel T Ksepka, Julia A Clarke, Lance GrandeAbstract:Abstract A new species of stem parrot is reported from the early Eocene Fossil Butte Member of the Green River Formation. Well-preserved specimens including a complete skeleton and referred partial postcranial skeleton reveal new osteological details of the clade Halcyornithidae and expand the known diversity of the Green River avifauna. Cyrilavis colburnorum n. sp. shares key morphologies with the smaller Green River halcyornithid Cyrilavis olsoni. A combined phylogenetic analysis of Pan-Psittaciformes using 101 morphological characters and sequence data from three genes (RAG-1, Z-chromosomal spindlin and cytochrome b) supports the placement of 1) Halcyornithidae, 2) a small clade uniting the Messel fossil taxon Psittacopes lepidus and an unnamed London Clay species, and 3) Quercypsittidae on branches successively closer to the crown clade Psittaciformes. Analysis of the morphological dataset alone yields a similar strict consensus tree with slightly less resolution (one additional branch collapsed). Rel...
Gerald Mayr - One of the best experts on this subject based on the ideXlab platform.
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A reassessment of Eocene parrotlike fossils indicates a previously undetected radiation of zygodactyl stem group representatives of passerines (Passeriformes)
Zoologica Scripta, 2015Co-Authors: Gerald MayrAbstract:In the past years, various Eocene fossil birds were described as stem group representatives of the zygodactyl Psittaciformes (parrots). These birds show quite disparate morphologies, which cast some doubt on the correct assignment of all of them to the psittaciform stem group. A reassessment of their affinities is further needed, because it was recently proposed that among extant birds, Psittaciformes and Passeriformes (passerines) form a clade and that passerines possibly derived from a zygodactyl ancestor. Here, phylogenetic analyses are performed, which for the first time also include representatives of the Zygodactylidae, the extinct zygodactyl sister taxon of the Passeriformes. The early Eocene Psittacopes was originally described as a stem group representative of Psittaciformes. However, none of the present analyses supported psittaciform affinities for Psittacopes and instead recovered this taxon in a clade together with zygodactylids and passerines. Also part of this clade are the early Eocene taxa Pumiliornis and Morsoravis, and it is detailed that Psittacopes and the long-beaked and presumably nectarivorous Pumiliornis, with which it has not yet been compared, are very similar in their postcranial osteology. The present analysis corroborates the hypothesis of a zygodactyl stem species of passerines. To account for these results, Psittacopes is here assigned to a new higher-level taxon and a new name is also introduced for the clade including Zygodactylidae and Passeriformes.
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well preserved new skeleton of the middle eocene messelastur substantiates sister group relationship between messelasturidae and halcyornithidae aves pan Psittaciformes
Journal of Systematic Palaeontology, 2011Co-Authors: Gerald MayrAbstract:A virtually uncrushed skeleton of Messelastur gratulator from the Middle Eocene of Messel (Germany) is described, which for the first time preserves the feet of this poorly known avian species. The new fossil corroborates a close relationship between Messelastur and the early Eocene Tynskya eocaena, from which M. gratulator differs in its more raptor-like feet. The specimen further shows that the Messelasturidae are the sister taxon of the early Eocene Halcyornithidae (‘Pseudasturidae’), which are considered to be stem group representatives of the Psittaciformes. A sister group relationship between Messelasturidae and Halcyornithidae is supported by a phylogenetic analysis of 100 morphological characters, but concerning the extant taxa the results of the primary analysis conflict with current hypotheses on avian higher-level relationships. After constraints were enforced, the analysis resulted in a sister group relationship between the Messelasturidae/Halcyornithidae clade and Psittaciformes. Messelasturi...
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quercypsitta like birds from the early eocene of india aves Psittaciformes
Journal of Vertebrate Paleontology, 2010Co-Authors: Gerald Mayr, Rajendra S Rana, Kenneth D Rose, Ashok Sahni, Kishor Kumar, Lachham Singh, Thierry SmithAbstract:We report new avian remains from the early Eocene Cambay Formation of Vastan Lignite Mine in western India. Most of the bones belong to the as yet poorly known taxon Vastanavis, of which a new species, V. cambayensis, is described. For the first time, tarsometatarsi of Vastanavis can be identified, which show that this taxon had semi-zygodactyl feet. In overall morphology, Vastanavis closely resembles the species of the Quercypsittidae, which occur in the late Eocene of Europe and are considered stem group representatives of the parrots (Psittaciformes). Several plesiomorphic features indicate, however, that Vastanavis is outside a clade including Quercypsitta and crown group Psittaciformes, and we therefore assign it to a new family, Vastanavidae. Vastanavis corresponds well with an as yet undescribed avian species from the early Eocene London Clay in England, and we conclude that, at least concerning the arboreal taxa, the early Eocene avifauna of India shows some concordances with the much better known one from the early Eocene of Europe. We further describe a distal tarsometatarsus from Vastan Lignite Mine that superficially resembles that of extant New World vultures (Cathartidae), but comes from a roller-sized species.
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the phylogenetic affinities of the parrot taxa agapornis loriculus and melopsittacus aves Psittaciformes hypotarsal morphology supports the results of molecular analyses
Emu, 2008Co-Authors: Gerald MayrAbstract:The interrelationships between the currently recognised subtaxa of parrots (Psittaciformes) are poorly understood and even monophyly of some is not well established. A recent phylogenetic analysis of nuclear gene sequences strongly supports a previously unrecognised clade including Agapornis (lovebirds), Melopsittacus (Budgerigar), Cyclopsittini (fig-parrots) and Loriini (lories). In the present study it is shown that these taxa also share a unique derived morphology of the hypotarsus, which further occurs in Loriculus (hanging-parrots) and Micropsitta (pygmy-parrots). It is hypothesised that Agapornis, Loriculus, Micropsitta, Cyclopsittini, Melopsittacus and Loriini form a clade for which the name Loricoloriinae is proposed. The presence of an ossified arcus parahyalis on the hyoid bone further suggests a clade including Cyclopsittini, Melopsittacus and Loriini, which also gained support from analysis of molecular data.
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a new parrot from the miocene of germany with com ments on the variation of hypotarsus morphology in some Psittaciformes
Belgian Journal of Zoology, 2004Co-Authors: Gerald Mayr, Ursula B Gohlich, Forschungsinstitut SenckenbergAbstract:A new taxon of parrot (Psittaciformes) is described from the Middle Miocene of Southern Germany. Bavaripsitta ballmanni gen. et sp. n. is known from an almost complete tarsometatarsus which resembles the corre- sponding bone of some small Psittaculini (Polytelis, Alisterus) and Platycercini (e.g., Psephotus spp.) in general shape and morphology. Although the new taxon cannot be assigned to any of the modern groups of parrots, together with other fossil specimens it shows that there was a considerable diversity of parrots in the Lower and Middle Miocene of the Old World. Our study further provides the first detailed survey on the variation of hypotarsus mor- phology within extant Psittaciformes. A derived hypotarsal structure is described that supports monophyly of a clade including the genera Psephotus, Eunymphicus, Cyanoramphus, Northiella, Prosopeia, Barnardius, Platycer- cus, and Melopsittacus, to the exclusion of Neophema and Neopsephotus (all Platycercini). Also well characterized by a derived morphology of the hypotarsus are Loriinae and Cyclopsittacini. A shared derived hypotarsal morphol- ogy may further support sister group relationship between Agapornis and Loriculus (Psittaculini).
N V Zelenkov - One of the best experts on this subject based on the ideXlab platform.
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anatomy of the forelimb musculature and ligaments of psittacus erithacus aves Psittaciformes
Journal of Anatomy, 2018Co-Authors: Daria Razmadze, Aleksandra A Panyutina, N V ZelenkovAbstract:: Parrots (order Psittaciformes) are a rather homogeneous group of birds that can be easily distinguished by the notably modified morphology of the skull and hindlimb. Detailed description of the forelimb morphology in these birds has never been provided, though parrots are often used as model objects in flight studies. Parrots are also considered the closest living relatives of the perching birds (Passeriformes), and thus knowledge of the wing morphology in Psittaciformes is important for understanding the evolution of the locomotor apparatus on the way to the most speciose group of birds. Here we provide a comprehensive illustrated description of the wing morphology (musculature and ligaments) of the African grey parrot (Psittacus erithacus) and compare it with several closely related taxa of the high clade Eufalconimorphae and more distantly related outgroups (based on personal dissections and literature data). We note a general similarity of the wing musculature between P. erithacus and Falconidae. A number of features common with the outgroup Columbidae supports a generally plesiomorphic structure of the forelimb in parrots as compared with the Passeriformes. Nevertheless, the wing of the Psittaciformes displays a series of structural (likely autapomorphic) modifications, which can be explained in terms of adaptations for flight with vertical body. An analysis of the anatomical data for parrots (ratio of wing elevators and highly unusual development of the M. supracoracoideus), which is based on the current experiment-based knowledge of the flapping flight in birds, allows us to hypothesize that parrots are able to produce useful aerodynamic force during the upstroke, which is also known for pigeons and hummingbirds. This supposed ability of vertical flight and the zygodactyl foot together link the origin of parrots with the dense (likely tropical) forests.
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the first fossil parrot aves Psittaciformes from siberia and its implications for the historical biogeography of Psittaciformes
Biology Letters, 2016Co-Authors: N V ZelenkovAbstract:Modern parrots (crown Psittaciformes) are a species-rich group of mostly tropical and subtropical birds with a very limited fossil record. A partial tarsometatarsus from the late Early Miocene of Siberia (Baikal Lake) is the first pre-Quaternary find of crown Psittaciformes in Asia (and Siberia in particular) and is also the northern-most find of this bird order worldwide. This find documents a broad geographical distribution of parrots during the warmest phase of the Miocene (the so-called ‘Miocene Climatic Optimum’), which has implications for the historical biogeography of Psittaciformes. The presence of parrots on both sides of the Pacific Ocean at the end of the Early Miocene implies a (most probably eastwards) trans-Beringian dispersal which likely took place about 16–18 Ma. The broad Eurasian distribution of parrots in the past further supports a hypothesis that ancestors of modern genera Coracopsis and Agapornis could reach Africa from Eurasia.
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two new parrots Psittaciformes from the lower eocene fur formation of denmark
Palaeontology, 2008Co-Authors: David M Waterhouse, N V Zelenkov, Bent E K Lindow, Gareth J DykeAbstract:Two new fossil psittaciform birds from the Lower Eocene 'Mo Clay' (Fur Formation) of Denmark (c. 54 Ma) are described. An unnamed specimen is assigned to the extinct avian family of stem-group parrots, Pseudas- turidae (genus and species incertae sedis), while a second (Mopsitta tanta gen. et sp. nov.) is the largest fossil parrot yet known. Both specimens are the first fossil records of these birds from Denmark. Although the phylogenetic posi- tion of Mopsitta is unclear (it is classified as family incer- tae sedis), this form is phylogenetically closer to Recent Pstittacidae than to other known Palaeogene psittaciforms and may, therefore, represent the oldest known crown- group parrot.
David M Waterhouse - One of the best experts on this subject based on the ideXlab platform.
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two new parrots Psittaciformes from the lower eocene fur formation of denmark
Palaeontology, 2008Co-Authors: David M Waterhouse, N V Zelenkov, Bent E K Lindow, Gareth J DykeAbstract:Two new fossil psittaciform birds from the Lower Eocene 'Mo Clay' (Fur Formation) of Denmark (c. 54 Ma) are described. An unnamed specimen is assigned to the extinct avian family of stem-group parrots, Pseudas- turidae (genus and species incertae sedis), while a second (Mopsitta tanta gen. et sp. nov.) is the largest fossil parrot yet known. Both specimens are the first fossil records of these birds from Denmark. Although the phylogenetic posi- tion of Mopsitta is unclear (it is classified as family incer- tae sedis), this form is phylogenetically closer to Recent Pstittacidae than to other known Palaeogene psittaciforms and may, therefore, represent the oldest known crown- group parrot.
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parrots in a nutshell the fossil record of Psittaciformes aves
Historical Biology, 2006Co-Authors: David M WaterhouseAbstract:Parrots (traditional order Psittaciformes) are one of the most instantly recognizable groups of modern birds. Their relatively large heads, squat necks and broad, curved bills help to make parrots so easily identifiable. However, the few early fossil parrots that have been discovered to date (Lower Eocene), do not necessarily possess this “parrot-like” cranial morphology. Even more surprisingly, early psittaciforms have mainly been found in the northern hemisphere (Walton-on-the-Naze, England; Messel, Germany, etc.), with only a few, relatively recent, essentially modern parrot remains being found within their present range (mainly in tropical and sub-tropical Australasia and South America). Fossil parrots remain rare and those that have been identified are often the subject of much debate. This paper is an attempt to accumulate and re-evaluate the current information available on parrot fossils—an intriguing group of birds with a complicated and elusive past.
Daniel T Ksepka - One of the best experts on this subject based on the ideXlab platform.
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a new stem parrot from the green river formation and the complex evolution of the grasping foot in pan Psittaciformes
Journal of Vertebrate Paleontology, 2012Co-Authors: Daniel T Ksepka, Julia A ClarkeAbstract:ABSTRACT Deposits from the Fossil Butte Member of the Green River Formation preserve exceptional fossils from one of the most diverse Paleogene avifaunas worldwide. Stem lineage parrots are well represented in this avifauna. Here we report a new species of Pan-Psittaciformes (crown clade parrots and their stem lineage relatives). The new species shares several features with extant parrots that are not present in the contemporaneous clades Halcyornithidae and Messelasturidae, including a wider pelvis, deeper trochlea cartilaginis tibialis, and larger pygostyle. Morphology of the foot suggests strong grasping ability and an arboreal ecology. Phylogenetic analysis of a combined data set of morphological and molecular sequence data resulted in limited support for a sister-group relationship between the new taxon and Quercypsittidae as well as a previously unrecognized clade including Vastanavidae, Halcyornithidae, and Messelasturidae. Regardless of whether this phylogeny or alternate hypotheses are preferred,...
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stem parrots aves halcyornithidae from the green river formation and a combined phylogeny of pan Psittaciformes
Journal of Paleontology, 2011Co-Authors: Daniel T Ksepka, Julia A Clarke, Lance GrandeAbstract:Abstract A new species of stem parrot is reported from the early Eocene Fossil Butte Member of the Green River Formation. Well-preserved specimens including a complete skeleton and referred partial postcranial skeleton reveal new osteological details of the clade Halcyornithidae and expand the known diversity of the Green River avifauna. Cyrilavis colburnorum n. sp. shares key morphologies with the smaller Green River halcyornithid Cyrilavis olsoni. A combined phylogenetic analysis of Pan-Psittaciformes using 101 morphological characters and sequence data from three genes (RAG-1, Z-chromosomal spindlin and cytochrome b) supports the placement of 1) Halcyornithidae, 2) a small clade uniting the Messel fossil taxon Psittacopes lepidus and an unnamed London Clay species, and 3) Quercypsittidae on branches successively closer to the crown clade Psittaciformes. Analysis of the morphological dataset alone yields a similar strict consensus tree with slightly less resolution (one additional branch collapsed). Rel...
