Fossil Birds

In the Tagus Valley there are five Pleistocene deposits with the presence of skeletal remains of birds. With some exceptions, the species of birds that lived in Pleistocene are the same that exist in Portugal today. On Pleistocene, birds are only known in the context of human occupation of caves. Birds had a secondary importance to the human groups of Palaeolithic period, because the majority of Pleistocene birds found in these deposits are not edible species and many of them live or frequently appear in caves. For this reason we believe that almost all Pleistocene remains of birds, found in caves are not of human origin.

Coucals are large, predatory, primarily ground-dwelling cuckoos of the genus Centropus, with 26 extant species ranging from Africa to Australia. Their evolutionary and biogeographical history are poorly understood and their fossil record almost non-existent. Only one species (Centropus phasianinus) currently inhabits Australia, but there is now fossil evidence for at least three Pleistocene species. One of these (Centropus colossus) was described from southeastern Australia in 1985. Here we describe additional elements of this species from the same site, and remains of two further extinct species from the Thylacoleo Caves of the Nullarbor Plain, south-central Australia. The skeletal morphology and large size of the three extinct species indicates that they had reduced capacity for flight and were probably primarily ground-dwelling. The extinct species include the two largest-known cuckoos, weighing upwards of 1 kg each. They demonstrate that gigantism in this lineage has been more marked in a continental context than on islands, contrary to the impression gained from extant species. The evolutionary relationships of the Australian fossil coucals are uncertain, but our phylogenetic analysis indicates a possible close relationship between one of the Nullarbor species and extant Centropus violaceus from the Bismarck Archipelago. The presence of three coucals in southern Australia markedly extends the geographical range of the genus from tropical Australia into southern temperate regions. This demonstrates the remarkable and consistent ability of coucals to colonize continents despite their very limited flying ability.

A new Anseriformes, Conflicto antarcticus gen. et sp. nov., represented by associated bones of a single individual,
from the early Palaeocene of Antarctica is described. The new taxon is unlike any other known member of the order.
Conflicto antarcticus is a medium-sized (2 kg) stem anseriform. The forelimb and pectoral girdle bones suggest that
it was a flying bird, and the bones of the hindlimb show that it had elongated legs. The os quadratum represents a
unique combination of features; some are similar to the features of the ancestral quadrate for galloanserines and some
are similar to Anseriformes, but features such as the presence of three foramina are exclusive among Neornithes.
The incisura or foramen nervi suracoracoidei is absent in C. antarcticus, as in most anatids and all Galliformes.
Phylogenetic analysis shows that C. antarcticus + Anatalavis oxfordi is the most basal stem Anseriformes clade. This
implies that the duck-type beak must have developed at an early stage of anseriform evolution. Conflicto antarcticus
represents one (and possibly the most) substantial record of a non-marine Palaeocene bird from the Southern
Hemisphere and supports the hypothesis that Neognathae had already diversified in the earliest Palaeocene.

The giant flightless bird Sylviornis neocaledoniae (Aves: Sylviornithidae) existed on La Grande Terre and Ile des Pins, New Caledonia, until the late Holocene when it went extinct shortly after human arrival on these islands. The species was generally considered to be a megapode (Megapodiidae) until the family Sylviornithidae was erected for it in 2005 to reflect multiple cranial autapomorphies. However, despite thousands of bones having been reported for this unique and enigmatic taxon, the postcranial anatomy has remained largely unknown. We rectify this deficiency and describe the postcranial skeleton of S. neocaledoniae based on ~600 fossils and use data from this and its cranial anatomy to make a comprehensive assessment of its phylogenetic affinities. Sylviornis neocaledoniae is found to be a stem galliform, distant from megapodiids, and the sister taxon to the extinct flightless Megavitiornis altirostris from Fiji, which we transfer to the family Sylviornithidae. These two sp...

The penguins (Aves: Sphenisciformes) are the most derived group of diving seabirds. Exclusive to the Southern Hemisphere, ten of the seventeen extant species can be found in South America. South America has been recognised as one of the richest areas with fossil penguins worldwide, but until the late twentieth century this record was limited to the Argentinian Patagonia. Only at the beginning of this century were the first species from southern Peru and northern Chile described. Currently, seventeen palaeospecies have been described for South America, with a chronostratigraphic range from Middle Eocene to Late Pliocene. Traditionally the study of fossil penguins has been made on the basis of isolated specimens, with the humerus and tarsometatarsus being the most widely used elements for the typification of species. However, recently the number of skulls and partial skeletons discovered in South America has significantly increased, facilitating their interpretation and use in phylogenetic analyses. This work summarizes the fossil record of Sphenisciformes on the continent, based on type specimen revisions and the compilation of bibliographic data.

The present review aims to improve the scope and coverage of the phylogenetic matrices currently in use, as well as explore some aspects of the relationships among Paleogene penguins, using two key skeletal elements, the humerus and tarsometatarsus. These bones are extremely important for phylogenetic analyses based on fossils because they are commonly found solid specimens, often selected as holo− and paratypes of fossil taxa. The resulting dataset includes 25 new characters, making a total of 75 characters, along with eight previously uncoded taxa for a total of 48. The incorporation and analysis of this corrected subset of morphological characters raise some interesting questions consider− ing the relationships among Paleogene penguins, particularly regarding the possible exis− tence of two separate clades including Palaeeudyptes and Paraptenodytes, the monophyly of Platydyptes and Paraptenodytes, and the position of Anthropornis. Additionally, Noto− dyptes wimani is here recovered in the same collapsed node as Archaeospheniscus and not within Delphinornis, as in former analyses.

The Australian pre-Pleistocene fossil record of Accipitridae (eagles, hawks, old-world vultures) comprises one latest Oligocene or early Miocene and one middle Miocene species, each represented by partial bones. Globally, most fossil accipitrids are based on single bones. The recent discovery of an older and considerably more complete accipitrid from late Oligocene sediments in Australia is therefore significant. It is derived from the Pinpa Local Fauna from the Namba Formation at Lake Pinpa, South Australia (~26-24 Ma). The fossil, described as Archaehierax sylvestris gen. et sp. nov., represents a raptor that was larger than the blackbreasted buzzard Hamirostra melanosternon but smaller and more gracile than the wedge-tailed eagle Aquila audax. Comprehensive morphological and molecular phylogenetic analyses resolved Archaehierax as a basal accipitrid, not closely related to any living subfamily and perhaps the sister taxon to all other accipitrids exclusive of elanines. Relatively short wings similar to species of Spizaetus and Spilornis suggest it was adapted for flight within enclosed forests. Additional accipitrid fossils from the Namba Formation, a distal femur and a distal humerus, are incomparable with the holotype of A. sylvestris; they may represent distinct species or smaller individuals of the new taxon. lsid:zoobank.org:pub:6A25C569-3E9F-43B8-AAF8-F36CE405C06E ARTICLE HISTORY

A comparison between the Paleogene and Neogene marine assemblages in South America suggests a major turnover among penguins by the late Miocene, with the disappearance of the stem Sphenisciformes and the rise of the modern penguins. However, isolated specimens attributed to Palaeospheniscus from the late Miocene of Chile suggest that stem and crown taxa coexisted until the end of the Miocene. To clarify the stratigraphic range of Palaeospheniscus and determine how long the stem Sphenisciformes persisted in South America, the present study offers a revision of its putative records in Chile (Bahía Inglesa and Coquimbo formations), Peru (Chilcatay Formation), and South Africa (Ysterplaats site). In order to reliably discriminate isolated humeri of Palaeospheniscus from Spheniscus, twelve potential discriminating characters were identified and evaluated. Despite the existence of a wide range of variability and overlap, these humeri can be discriminated using large sets of characters, such as a transverse ligament sulcus connected with the capital incisure by a sulcus, or the lack of the proximal ligament pit in Palaeospheniscus. The putative record of Palaeospheniscus in the late Miocene–Pliocene of Chile and early Pliocene of South Africa is discarded, restricting its stratigraphic range to the early and middle Miocene of Argentina and the middle Miocene of Peru. This reduces the biochron of the genus from 18 Ma to a maximum of 11 Ma and suggests that the middle Miocene was a crucial time for the establishment of modern seabirds communities in general and penguins in particular.

Among Charadriiformes (shorebirds and allies), Charadrii (plovers and allies) have the poorest fossil record. The lacustrine, early Miocene deposits of Saint-Gérand-le-Puy in France have yielded several charadriiform birds, but so far no members of the Charadrii. We identified a Haematopus (oystercatcher)-like skull from the early Miocene locality of Montaigu-le-Blin, in the Saint-Gérand-le-Puy area. Affinities to extant Haematopodidae are, apart from an overall similarity, supported by two features of the occipital region not present in any other of the examined charadriiforms. The fossil nevertheless differs from recent oystercatchers in some osteological features, including much shallower temporal fossae. Additionally, we report two fossil remains of plover-like Charadrii, a humerus and a tarsometatarsus, which also represent the first record of this charadriiform clade in Saint-Gérand-le-Puy. The specimens resemble the corresponding bones of Charadriidae but a definitive assignment to that taxon is not possible.

The fossil record of South American cathartids, with few exceptions, is largely restricted to Late Pleistocene and
Holocene sites. This contribution provides for the first time fossil records of cathartids from Uruguay. The
specimens reported here include an; almost complete fibula, an incomplete furcula, and the distal end of a
tibiotarsus. The; first two specimens came from Late Pleistocene beds at two localities of from Northern Uruguay,
and the last one comes from Late Pleistocene-Early Holocene beds from South-western Uruguay. All the specimens
were associated with several megafaunal fossil remains. The systematic assignation and paleobiological
implications of these scavenger birds are here discussed.

During the last decade, new Neogene fossil assemblages from South America have revealed important clues about the evolution of seabird faunas in one of the major upwelling systems of the world: the Humboldt Current. However, most of this record comes from arid Northern Chile and Southern Peru and, in consequence, our knowledge of the evolutionary history of seabirds in the temperate transitional zone is negligible. A new Late Pliocene assemblage of fossil birds from the coastal locality of Horcon in Central Chile offers a unique opportunity to fill this gap. Isolated bones of a medium-sized penguin are the most abundant bird remains. Morphological and cladistic analyses reveal that these specimens represent a new species of crested penguin, Eudyptes calauina sp. nov. Eudyptes is a penguin genus that inhabit temperate and subantarctic regions and currently absent in central Chile. Additionally, a partial skeleton of a small species of cormorant and a partial tarsometatarsus of a sooty shearwater have been identified. The Horcon fossils suggest the existence of a mixed avifauna in central Chile during the Pliocene in concordance with the latitudinal thermal gradient. This resembles the current assemblages from the transitional zone, with the presence of species shared with Northern Chile and Southern Peru and a previously unrecorded penguin currently absent from the Humboldt System but present in the Magellanic region. Comparison of Pliocene seabird diversity across the Pacific coast of South America shows that the Horcon avifauna represents a distinctive assemblage linking the living faunas with the Late Miocene ones. A comparison with the fossil record near the Benguela Current (west coast of southern Africa) suggests that the thermic gradient could play an important role in the preservation of a higher diversity of cold/temperate seabirds in the Humboldt Current.

The first unequivocal records of teratornithid birds from the Pleistocene of South America are here described, adding a new member, and the largest, to this highly diversified guild of large carnivorous flying birds that lived during these times in the Americas. The new specimens come from four fossiliferous localities of Central Argentina that range in age from the late middle to the early late Pleistocene, and agree with other known Teratornithidae taxa in size and morphology. We updated the taxonomy of the family and analyzed its fossil record in the Pleistocene of both Americas. The available evidence suggests that forms related to Teratornis lived in the South American Pampas around the time of the Last Interglacial (MIS 5), but they were restricted to North America during the latest Pleistocene (late MIS 3–early MIS 1). The contrasting latest Pleistocene record of teratorns between North and South America is not easy to understand, especially because the supposed flight capaci...

This is a brief study on the paleoecological and paleoenvironmental indicators provided by the research on the remains of birds present at the Portuguese Pleistocene deposits. This work is based on the study of the remains of birds found in nine of the Pleistocene deposits and the data resulting from studies on seven other deposits, already published. The time lapse between these pleistocenic stations lies between 240,000 years BP (Galerias Pesadas) and 10,000 years BP (Gruta do Caldeirão), showing that during this period there was no significant change in environments associated with the bird species bird found in the different deposits. A short comparison with the present avifauna is added, based on census and inventaries which render possible the creation of atlas and the monitoring of the species actual conservation status.

Recent paleontological investigations at Laetoli and neighboring localities in northern Tanzania have produced a large collection of fossil ostrich eggshells from the Pliocene-aged Laetolil Beds ($3.5-4.5 Ma) and Ndolanya Beds ($2.6-2.7 Ma). A detailed analysis of the morphology of the eggshells and their taxonomic affinities indicates that two different species of Struthio are represented. In the Lower Laetolil Beds and in the Upper Laetolil Beds below Tuff 3 a new species is recognized-Struthio kakesiensis. This is replaced in the Upper Laetolil Beds by Struthio camelus, the modern species of ostrich. Since radiometric age determinations are available for the stratigraphic sequence at Laetoli, it is possible to precisely date the first appearance of S. camelus at $3.6-3.8 Ma. Comparisons of the Laetoli material with specimens from the well-dated sequences at Lothagam and Kanapoi in northern Kenya, allow the taxonomic and biochronological analysis to be extended back in time to the late Miocene.

All fossil bird orders recorded from the Mesozoic and Cenozoic periods in deposits of Chile and the Antarctic Peninsula have been summarized. Chilean insular territory and quaternary records have been excluded. The Bahía Inglesa Formation located in Copiapó province in northern Chile and the La Meseta Formation of Seymour Island have been identified as the richest fossiliferous fossil bird-bearing localities for Chile and the Antarctic Peninsula respectively. The importance of these records as indicators of paleoenvironmental conditions is discussed.

Se presentan los primeros restos diagnósticos asignables a Spheniscus megaramphus procedentes del Miembro Bonebed de la Formación Bahía Inglesa (Mioceno tardío), consistentes en tres rostros aislados pertenecientes a la colección del Museo Paleontológico de Caldera, Chile. Se rectifica la antigüedad de la especie en el Perú, previamente asociada al Mesiniano (6 Ma) y actualmente referida al Tortoniano (9.5-9 Ma). El presente estudio confirma la existencia de esta especie en Chile, ampliando el rango de incidencia de la especie hasta los 27º S durante el Mioceno tardío. ABSTRACT The first diagnostic remains assignable to Spheniscus megaramphus coming from the Bonebed Member of the Bahia Inglesa Formation (Late Mioceno) are presented. These consist of three isolated rostrums from the collection of the Museo Paleontologico de Caldera, Chile. The antiquity of the species is rectified in Peru previously associated to the Mesinian (6 My) and at the moment referred to the Tortonian (9.5-9 My). The present study confirms the existence of this species in Chile enlarging the range of incidence of the species until the 27º S during the Late Miocene.

Three new penguin skulls (Spheniscidae), assigned to the new species Pygoscelis calderensis sp. nov. from the Bahía Inglesa Formation of Middle Miocene-Pliocene age located south of Caldera on the coast of the III Región de Atacama, Chile (27°00'S, 70°45'W to 28°00', 71°00'W), are described. This finding broadens the geographic and chronologic distribution of the genus, constituting its most northern record. Before the present work, the genus was known from the Late Pliocene of New Zealand. This record, together with other faunistic evidences, suggests the existence of periods or cold oceanic currents during the Neogene.

Recent paleontological investigations at the Pliocene site of Laetoli and at neighboring localities on the Eyasi Plateau of northern Tanzania have led to the recovery of a sizable collection of fossil bird eggs. The material comes from the Upper Laetolil Beds, dated at 3.6-3.8 Ma, and the Lower Laetolil Beds, dated at 3.8 Ma to older than 4.3 Ma. The preservation of relatively complete eggs (other than those of ratites) is an extremely rare occurrence in the fossil record, and Laetoli is the only locality in Africa that has produced such well-preserved eggs. Deposition of carbonatite air-fall tuffs led to the rapid burial of the eggs sub-aerially, and they were then preserved in paleosols that were geochemically conducive to their preservation.

Presbyornithids were the dominant birds in Palaeogene lacustrine assemblages, especially in the Northern Hemisphere, but are thought to have disappeared worldwide by the mid-Eocene. Now classified within Anseriformes (screamers, ducks, swans and geese), their relationships have long been obscured by their strange wader-like skeletal morphology. Reassessment of the late Oligocene South Australian material attributed to Wilaru tedfordi , long considered to be of a stone-curlew (Burhinidae, Charadriiformes), reveals that this taxon represents the first record of a presbyornithid in Australia. We also describe the larger Wilaru prideauxi sp. nov. from the early Miocene of South Australia, showing that presbyornithids survived in Australia at least until ca 22 Ma. Unlike on other continents, where presbyornithids were replaced by aquatic crown-group anatids (ducks, swans and geese), species of Wilaru lived alongside these waterfowl in Australia. The morphology of the tarsometatarsus of t...

The present comment was motivated by the article by Acosta-Hospitaleche & Canto (2005), and from the direct observation of some specimens of Sphenicidae previously reported for the Bahia Inglesa Formation, in the Atacama region, Chile. The lack of morphological characters that they allow the differentiation with the genus Spheniscus and of associate diagnostic remains discard the assignment of cranial materials to Palaeospheniscus. Equally it is not possible to corroborate the assignment of specimens to Paraptenodytes, being suggested the use of Spheniscidae indet. aff. Paraptenodytes for an isolated tarsometatarsus. It is also suggested the use of Spheniscus spp. for the specimens previously referred to S. cf. chilensis and S. aff. humboldti. This way, the number of penguins registered in the formation decreases from nine to seven.

We describe novel material of a small fossil burhinid (Stone-curlew, thick-knee; Aves: Charadriiformes) from the late Oligocene (ca 23 Ma) of Coderet-Bransat in the Allier Basin of central France. This site is one of the renowned Saint-Gérand-le-Puy fossil localities, which have yielded thousands of fossil bird specimens. This is the first record of the Burhinidae to be described from Paleogene and Neogene deposits of Europe, and, together with the late Oligocene-early Miocene burhinid from Australia, are the earliest records worldwide. Although Genucrassum bransatensis gen. et sp. nov. differs from extant burhinids in some presumably plesiomorphic features of the humerus and carpometacarpus, we show that the postcranial elements considered here are remarkably uniform within Burhinidae even in late Oligocene taxa. Keywords Genucrassum bransatensis gen. et sp. nov. Á Coderet-Bransat Á Saint-Gérand-le-Puy Á Fossil birds Á Thick-knees Á Burhinus Zusammenfassung Frü hester Nachweis eines Triels (Charadriiformes, Burhinidae) in Europa aus dem spät-Oligozän Frankreichs Wir beschreiben neues Material eines kleinen fossilen Triels (Burhinidae, Charadriiformes) aus dem späten-Oligozän (ca 23 Ma) von Coderet-Bransat im Allier Becken in Zentral-Frankreich. Diese Fossil-Lokalität gehört zu den renommierten Saint-Gérand-le-Puy-Fossilfundstellen, welche tausende von fossilen Vogelreste geliefert haben. Das neue Fossil ist der erste Nachweis von Burhinidae in paläogenen und neogenen Ablagerungen Europas, und zusammen mit einem Triel aus dem späten-Oligozän/frühen-Miozän Australiens, stellt es den weltweit frühesten Nachweis dar. Obwohl Genucrassum bransatensis gen. et sp. nov. anhand mutmasslich plesiomorphe Merkmale am Humerus und Carpometacarpus von den Rezenten Burhiniden differenziert werden kann, zeigen wir, dass die untersuchten post-cranialen Elemente bemerkenswert einheitlich innerhalb der Burhinidae sind, und dies sogar in Taxa aus dem späten Oligozän. Communicated by F. Bairlein.

The magpie goose Anseranas semipalmata (Aves: Anseranatidae), the sole modern representative of the family, is endemic to Australia. The fossil record of Anseranatidae in Australia was until now restricted to Pliocene and younger sediments. Here we describe an anseranatid from the Oligo-Miocene Carl Creek Limestone in the Riversleigh World Heritage Property, Boodjamulla (Lawn Hill) National Park, in northwestern Queensland, as a new species and genus, based on a coracoid and two scapulae. These fossils extend the known age of the Anseranatidae lineage in Australia to about 25 million years ago. The fossil distribution of Anseranatidae now includes the Paleocene in North America, Eocene and Late Oligocene of Europe, and the Late Oligocene to earliest Miocene in Australia, indicating a globally widespread distribution of the family during the early-mid Tertiary.

Among Charadriiformes (shorebirds and allies), Charadrii (plovers and allies) have the poorest fossil record. The lacustrine, early Miocene deposits of Saint-Gerand-le-Puy in France have yielded several charadriiform birds, but so far no members of the Charadrii. We identified a Haematopus (oystercatcher)-like skull from the early Miocene locality of Montaigu-le-Blin, in the Saint-Gerand-le-Puy area. Affinities to extant Haematopodidae are, apart from an overall similarity, supported by two features of the occipital region not present in any other of the examined charadriiforms. The fossil nevertheless differs from recent oystercatchers in some osteological features, including much shallower temporal fossae. Additionally, we report two fossil remains of plover-like Charadrii, a humerus and a tarsometatarsus, which also represent the first record of this charadriiform clade in Saint-Gerand-le-Puy. The specimens resemble the corresponding bones of Charadriidae but a definitive assignm...

The magpie goose Anseranas semipalmata (Aves: Anseranatidae), the sole modern representative of the family, is endemic to Australia. The fossil record of Anseranatidae in Australia was until now restricted to Pliocene and younger sediments. Here we describe an anseranatid from the Oligo-Miocene Carl Creek Limestone in the Riversleigh World Heritage Property, Boodjamulla (Lawn Hill) National Park, in northwestern Queensland, as a new species and genus, based on a coracoid and two scapulae. These fossils extend the known age of the Anseranatidae lineage in Australia to about 25 million years ago. The fossil distribution of Anseranatidae now includes the Paleocene in North America, Eocene and Late Oligocene of Europe, and the Late Oligocene to earliest Miocene in Australia, indicating a globally widespread distribution of the family during the early-mid Tertiary.

In contrast to the rich record of eggs from non-avian dinosaurs, complete eggs attributable to Mesozoic birds are relatively scarce. Nevertheless, several well-preserved specimens have been discovered over the last three decades revealing functional and phylogenetic characters that shed light on the breeding strategies of extinct birds. Here we report the first fossil avian egg from Brazil, which was discovered in Upper Cretaceous strata of São Paulo in the southeastern part of the country. The taxonomic identity and structural features of the biomineralized tissues were determined using a combination of Scanning Electron Microscopy, Wave Dispersion Energy analyses and Computed Tomography. These show that the 125.5-μm-thick shell of the 31.4 × 19.5mm egg incorporates three structural layers of similar thickness with both prismatic and aprismatic boundaries. Close similarity between the Brazilian bird egg and those of enantiornithines from the Upper Cretaceous Bajo de la Carpa Format...

The first unequivocal records of teratornithid birds from the Pleistocene of South America are here described, adding a new member, and the largest, to this highly diversified guild of large carnivorous flying birds that lived during these times in the Americas. The new specimens come from four fossiliferous localities of Central Argentina that range in age from the late middle to the early late Pleistocene, and agree with other known Teratornithidae taxa in size and morphology. We updated the taxonomy of the family and analyzed its fossil record in the Pleistocene of both Americas. The available evidence suggests that forms related to Teratornis lived in the South American Pampas around the time of the Last Interglacial (MIS 5), but they were restricted to North America during the latest Pleistocene (late MIS 3-early MIS 1). The contrasting latest Pleistocene record of teratorns between North and South America is not easy to understand, especially because the supposed flight capacity of these birds did not prevent them from crossing large geographical barriers. Although a bias in the fossil record cannot be ruled out, it is possible that the teratorns were limited in South America by paleoclimatic-paleoecological factors as yet undetermined, and/or that the northern and southern Pleistocene species had very dissimilar specializations. In relation to the latter, the previous inferences on the teratorn paleobiology without phylogenetic support are preliminarily questioned here.

The Bird Remains from Ajdovska jama near Krško (Slovenia). -In this article five bones of avian origin from Ajdovska jama near Krško in Slovenia are described and depicted. These bones were found during the excavations in 2002 and are attributable to the following taxa: Gallus gallus, Turdus sp. aff. philomelos, Tetrao tetrix.

Resumen Se examina el registro neógeno de la extinta familia Pelagornithidae en las Formaciones Pisco (Perú) y Bahía Inglesa (Chile) en la costa pacífica de América del Sur. Se reportan nuevos especímenes pertenecientes al género Pelagornis, procedentes de los niveles Sacaco y Aguada de Lomas de la Formación Pisco, y del nivel fosfático de la Formación Bahía Inglesa. Asimismo se presentan elementos craneales y postcraneales de género indeterminado del nivel Montemar de la Formación Pisco y de la base de la misma, límite entre el nivel Cerro la Bruja y la Formación Chilcatay. Se compara el presente registro con los últimos antecedentes conocidos para la familia en el hemisferio sur. Se discute la problemática taxonómica del grupo y la correcta asignación de elementos fósiles a la familia. Se comenta sobre el actual conocimiento de la avifauna neógena dentro del área de estudio.