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EN
The early/middle Eocene Palaeotis weigelti is a flightless bird, which occurs in the fossil localities Messel and Geiseltal (Germany). The species is assigned to the Palaeognathae and some authors considered it to be a stem group representative of the Struthionidae (ostriches). Even though several partial skeletons have been found, the osteology of P. weigelti is incompletely known. In the present study, new details of the hindlimb morphology of the species are reported based on unpublished and previously described fossils from the Geiseltal. These data show that the recently described Galligeranoides boriensis from the early Eocene of southern France is another representative of the Palaeotididae and the oldest record of the taxon. It is further noted that Palaeogrus princeps from the middle Eocene of Italy, which was previously assigned to the Gruidae (cranes), may be another representative of the Palaeotididae. Galligeranoides was before assigned to the North American Geranoididae, a taxon mainly known from hindlimb elements. The Geranoididae are usually considered to be closely related to the Asian Eogruidae and both taxa are currently classified in the Gruiformes (cranes and allies). However, as detailed in the present study, derived similarities suggest close affinities between the Palaeotididae and Geranoididae. Eogruids were identified as stem group representatives of the palaeognathous Struthionidae by some earlier authors, and if close affinities between Palaeotididae and Geranoididae are corroborated in future analyses, palaeognathous affinities of the Eogruidae need to be critically revisited.
Acta Ornithologica
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2008
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tom 43
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nr 2
226-230
EN
The phylogenetic affinities and evolutionary history of the Madagascan Leptosomidae (Courol or "Cuckoo-roller") are reviewed to rectify erroneous accounts in the recent literature. These birds are not closely related to rollers, and multiple molecular and morphological data sets congruently support their position outside the clade including Coraciiformes sensu stricto (rollers and ground rollers), Piciformes (woodpeckers and allies), and Alcediniformes (kingfishers and allies). The recent discovery that Plesiocathartes, from the Eocene of Europe and North America, is a stem lineage representative of the Leptosomidae further shows that Pan-Leptosomidae were widely distributed across the Northern Hemisphere in the early Paleogene. The Courol is among the few avian taxa which qualify as "living fossils", and its persistence on Madagascar may have been facilitated by the absence of ecological factors that led to extinction of Pan-Leptosomidae elsewhere.
PL
W odpowiedzi na błędne ujęcia powtarzane w literaturze, praca ta zawiera rewizję filogenetycznych pokrewieństw i ewolucyjnej historii madagaskarskich kuroli Leptosomidae. Liczne molekularne and morfologiczne dane zgodnie wskazują, że ptaki te nie tylko nie są blisko spokrewnione z kraskami, ale nawet nie należą do kladu obejmującego kraskowe Coraciiformes sensu stricto (kraski i ziemnokraski), dzięciołowe Piciformes i zimorodkowe Alcediniformes. Co więcej, ostatnie odkrycie, że Plesiocathartes Gaillard, 1908 z eocenu Europy i Ameryki Płn. reprezentuje pienne Leptosomidae wykazuje, że Pan-Leptosomidae były szeroko rozpowszechnione we wczesnym paleogenie Półkuli Północnej. Kurol jest jednym z nielicznych ptasich taksonów, które kwalifikują się jako "żyjące skamieniałości", a jego przetrwanie na Madagaskarze jest zapewne wynikiem braku ekologicznych czynników, które doprowadziły do wymarcia Pan-Leptosomidae na pozostałych obszarach.
EN
A skull of a new pelecaniform bird is described from the Middle Eocene of Messel (Germany). Masillastega rectirostris gen. et sp. nov. is tentatively referred to the Sulidae (boobies and gannets). If this assignment is correct, the new taxon would represent the earliest fossil record of the family, preceding Sula ronzoni Milne−Edwards, 1867 from the lowermost Oligocene of France by about 15 million years. Masillastega rectirostris most distinctly differs from extant Sulidae in the proportionally longer beak which indicates that the Eocene taxon was not adapted to plunge−diving. Contrary to extant Sulidae, which are exclusively marine birds, Masillastega rectirostris was found in a freshwater deposit. It is the first pelecaniform bird known from Messel and one of the few large birds discovered at this site.
EN
Representatives of the avian taxon Zygodactylidae are among the most abundant small arboreal birds in the early Palaeogene of the Northern Hemisphere. Still, however, the osteology of these birds, which have recently been shown to be the sister taxon of the Passeriformes, is only incompletely known. Here we describe a new species of Primozygodactylus from the middle Eocene of Messel in Germany. The holotype specimen of P. eunjooae sp. nov. for the first time allows a detailed examination of the distal tarsometatarsus in one of the Messel zygodactylids. It also exhibits exceptionally well−preserved tail feathers which, most notably, are formed by a long central pair of rectrices. We further report on a new specimen of Primozygodactylus major, which is the largest zygodactylid from Messel. Being one of the few dissociated skeletons of Primozygodactylus, the new specimen shows some previously unknown osteological features of this taxon and allows a more detailed comparison with other zygodactylids.
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nr 3
EN
Fluvioviridavis platyrhamphus, a new genus and species of short-legged landbirds from the Lower Eocene Green fiver Formation (Wyoming, USA) is described. The taxon is known from a single, nearly complete and slightly dissociated skeleton which was made the paratype of the putative oilbird Prefica nivea Olson, 1987 (Steatornithidae, Caprimulgiformes). Apart from the greatly abbreviated tarsometatarsus, Fluvioviridavis especially corresponds to recent oilbirds in the unusually wide proximal end of the humerus. However, in other features, e.g., the shape of its much longer beak, the Eocene taxon is clearly distinguished from the recent oilbird (Steatornis). In contrast, Prefica nivea agrees with Steatornis in the shape of the mandible but differs in the much narrower proximal end of the humerus. At present, no derived character convincingly supports a classification of F. platyrhamphus into any of the higher avian taxa. The species is here classified 'order and family incertae sedis'. An isolated skull from the Middle Eocene of Messel (Hessen, Germany) is tentatively assigned to ?Fluvioviridavis sp., and associated bones from the Lower Eocene London Clay of Walton-on-the-Naze (Essex, England) might also be related to the genus Fluvioviridavis.
PL
W pracy opisano nowy rodzaj i gatunek krótkonogiego ptaka lądowego nazwanego Fluvioviridavis platyrhamphus, z wczesnoeoceńskiej formacji Green River (Wyoming, USA). Takson ten jest znany z jednego prawie kompletnego i nieco rozproszonego szkieletu, ustanowionego jako paratyp domniemanego kopalnego tłuszczaka Prefica nivea Olson, 1987 (Steatornithidae, Caprimulgiformes). Oprócz silnie skróconych kości skoku, Fluvioviridavis nawiązuje do współczesnych tłuszczaków bardzo szeroką nasadą kości ramiennej. Jednak pod innymi względami, np. kształtem znacznie bardziej wydłużonego dzioba, eoceński takson wyraźnie różni się od współczesnego tłuszczaka (Steatornis), natomiast Prefica nivea ma kształt szczęki podobny jak Steatornis, ale różni się odeń o wyraźnie węższą nasadą kości ramiennej. Obecnie nie można wskazać żadnej apomorfii przekonująco wiążącej F. platyrhamphus z jakimkolwiek taksonem wyższej rangi, toteż rodzaj i gatunek ten uznano w niniejszej pracy za reprezentujący ,,rodzinę i rząd incertae sedis". Pojedyncza czaszka ze środkowego eocenu Messel (Hesja, Niemcy) została prowizorycznie zaliczona do ?Fluvioviridavis sp.; do rodzaju Fluvioviridavis mogą też należeć kości z wczesnoeoceńskich iłów londyńskich (London Clay) z Walton-on-the-Naze (Essex, Anglia).
EN
We identified a second, perfectly preserved skeleton of the earliest known galliform bird, Gallinuloides wyomingensis Eastman. The new specimen clearly shows that G. wyomingensis does not belong to crown group Galliformes as assumed by earlier authors. In particular, the primitive presence of a deeply excavated, concave facies articularis scapularis at the coracoid precludes the inclusion of G. wyomingensis into crown group Galliformes. Gallinuloides wyomingensis is morphologically very similar to Paraortygoides messelensis Mayr, a nearly contemporaneous galliform from Messel, Germany. The exclusive presence of stem group galliform birds in pre−Oligocene deposits does not support the Gondwanan origin of Galliformes as evidenced by the Southern Hemisphere distribution of basal crown group members (Megapodiidae and Cracidae).
7
63%
EN
We describe new specimens of the oldest European passeriform bird from the early Oligocene of Germany. This bird has hitherto been known only from a poorly preserved skeleton and we report here a second slab of the same specimen and an additional fragmentary skull. The new specimens allow the description of a new species, Wieslochia weissi gen. et. sp. nov., which lacks apomorphies of crown group Oscines, the taxon including most extant and all European passeriform species. In overall osteology, Wieslochia most closely resembles extant Suboscines but these similarities may be plesiomorphic for Passeriformes. W. weissi differs from the stem species pattern hypothesized for Eupasseres in the morphology of the distal carpometacarpus, the absence of a hooked processus acrocoracoideus (coracoid), and the presence of furrows instead of certain canals on the hypotarsus, and may even be outside crown group Eupasseres, the clade including Oscines and Suboscines. Because the earliest European fossil record of oscine passerines is from the late Oligocene, passerines outside crown group Oscines may have colonized Europe before the arrival of Oscines from the Australian continental plate.
EN
We describe a new avian taxon, Itaboravis elaphrocnemoides, gen. et sp. nov., from the late Paleocene fissure fillings of São José de Itaboraí in Brazil. The species is represented by a coracoid and two humeri, which most closely resemble the corresponding elements of the taxon Elaphrocnemus, a proposed stem group representative of the Cariamae from the late Eocene and Oligocene of the Quercy fissure fillings in France. I. elaphrocnemoides is only the second species of small landbird known from the Paleocene of the Southern Hemisphere. It is tentatively classified in the Cariamae, but we also note morphological similarities of the humerus to that of the palaeognathous Tinamidae. We further describe a carpometacarpus, which exhibits a peculiar morphology not found in any other avian taxon. This bone also shares some features with tinamous and is of a size corresponding to that of I. elaphrocnemoides, but cannot be referred to this taxon with confidence. We finally report four morphologically different distal tibiotarsi, one of which may belong to Eutreptodactylus itaboraiensis, the only other small bird described from Itaboraí.
10
51%
EN
We describe a new avian taxon (Sanshuiornis zhangi gen. et sp. nov.) from Middle Eocene black oil shales in the Huayong Formation of Guangdong Province, south China. The specimen consists of a distal tibiotarsus and a complete foot with tarsometatarsus and pedal digits in articulation. A preliminary phylogenetic analysis does not resolve the affinities of the fossil, but the bones show resemblances to some “ciconiiform” birds. The peculiar hypotarsus morphology, which is block−like and exhibits four cristae, resembles that of the early Eocene Rhynchaeites, which is a stem group representative of the Threskiornithidae. The new Chinese fossil has, however, proportionally longer legs than Rhynchaeites and its phylogenetic affinities probably cannot be resolved without further material.
EN
We report a new specimen of the extinct procellariiform species Diomedeoides brodkorbi (Aves, Diomedeoididae) from the early Oligocene (Rupelian) of Rheinweiler in southwestern Germany. The well−preserved partial skeleton allows the recognition and reassessment of new osteological details that bear on the phylogenetic affinities of diomedeoidids. The presence on the coracoid of a deeply excavated, cup−like facies articularis for the scapula suggests a stem group position of the Diomedeoididae within Procellariiformes, because this trait also occurs in stem−group representatives of several avian groups, as well as in Mesozoic non−neornithine birds, and is a plesiomorphic character. We hypothesize that the similarities of Diomedeoides to extant southern storm−petrels (Oceanitinae), such as the long mandibular symphysis, the small processus supracondylaris dorsalis and the long legs are plesiomorphic for Procellariiformes.
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