''Palaeoscinis'' (meaning "ancient oscine") is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

songbird A songbird is a bird belonging to the suborder Passeri of the perching birds (Passeriformes). Another name that is sometimes seen as the scientific or vernacular name is Oscines, from Latin ''oscen'', "songbird". The Passeriformes contains 5000 ...

described in 1957 from the middle

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

of the

Monterey Formation The Monterey Formation is an extensive Miocene oil-rich geological sedimentary formation in California, with outcrops of the formation in parts of the California Coast Ranges, Peninsular Ranges, and on some of California's off-shore islan ...

Santa Barbara, California Santa Barbara ( es, Santa Bárbara, meaning "Saint Barbara") is a coastal city in Santa Barbara County, California, of which it is also the county seat. Situated on a south-facing section of coastline, the longest such section on the West Co ...

. It is assigned to the extinct

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Palaeoscinidae, and contains the type and only species ''P. turdirostris''. The fossil was first discovered in 1955 on two slabs of

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

intended for use as

flagstones Flagstone (flag) is a generic flat Rock (geology), stone, sometimes cut in regular rectangular or square shape and usually used for Sidewalk, paving slabs or walkways, patios, flooring, fences and roofing. It may be used for memorials, headstone ...

before being recognised for their significance. It was preserved partly as an imprint of the skeleton with some of bones still intact and in articulation with only slight separation of individual bones, including scattered tracheal rings. The fossil was found in marine sediments, but the anatomy of ''Palaeoscinis'' indicates that it was a songbird rather than a

seabird Seabirds (also known as marine birds) are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same enviro ...

. The specific name was chosen for the thrush-like shape of its beak. The beak is long and slender, similar to that of the modern varied thrush, and its body proportions are also generally similar to thrushes. The legs are relatively short, though, unlike thrushes, and are shorter than the bones of the wing. Feather imprints on the slab suggest the wings may have been relatively short, although it is possible that they were not fully preserved. The foot is typical of songbirds, with a reversed 1st toe and three forward facing ones, of which the middle is the longest and the 2nd is the shortest, with the 1st and 4th toes roughly equal in length. The three forward facing claws are short, but the claw of the reversed 1st toe is long, approximately 70% the length of the preceding

toe bone Toes are the digits (fingers) of the foot of a tetrapod. Animal species such as cats that walk on their toes are described as being ''digitigrade''. Humans, and other animals that walk on the soles of their feet, are described as being ''plant ...

. ''Palaeoscinus'' was assigned to its own family due to the combination of skeletal characteristics (mostly of the

sternum The sternum or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major blood vessels from injury. Sha ...

shoulder The human shoulder is made up of three bones: the clavicle (collarbone), the scapula (shoulder blade), and the humerus (upper arm bone) as well as associated muscles, ligaments and tendons. The articulations between the bones of the shoulder mak ...

, and humerus) and its proportions being unlike any modern or fossil family of songbirds. However, it was regarded as similar and possibly related to the

Pycnonotidae The bulbuls are members of a family, Pycnonotidae, of medium-sized passerine songbirds, which also includes greenbuls, brownbuls, leafloves, and bristlebills. The family is distributed across most of Africa and into the Middle East, tropical ...

(bulbuls),

Bombycillidae The waxwings are three species of passerine birds classified in the genus ''Bombycilla''. They are pinkish-brown and pale grey with distinctive smooth plumage in which many body feathers are not individually visible, a black and white eyestri ...

(waxwings),

Corvidae Corvidae is a cosmopolitan family of oscine passerine birds that contains the crows, ravens, rooks, jackdaws, jays, magpies, treepies, choughs, and nutcrackers. In colloquial English, they are known as the crow family or corvids. Cu ...

, or Cinclidae (dippers) by Howard (1957). It was provisionally allocated as closest to the Pycnonotidae over the other families by Wetmore (1960) based on its proportions, although this relationship is not certain. The area has produced fossils of other marine animals, including fossils of a

shearwater Shearwaters are medium-sized long-winged seabirds in the petrel family Procellariidae. They have a global marine distribution, but are most common in temperate and cold waters, and are pelagic outside the breeding season. Description These tub ...

and the "pseudo-toothed"

pelagornithid The Pelagornithidae, commonly called pelagornithids, pseudodontorns, bony-toothed birds, false-toothed birds or pseudotooth birds, are a prehistoric family of large seabirds. Their fossil remains have been found all over the world in rocks datin ...

'' Osteodontornis'', as well as a porpoise and fish, alongside fossils of palms.

References

* * * Fossil taxa described in 1957 Miocene birds of North America Songbirds {{Paleo-bird-stub