| Pulchrapollia | |
|---|---|
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | †Halcyornithiformes |
| Family: | †Halcyornithidae |
| Genus: | †Pulchrapollia Dyke & Cooper, 2000 |
| Type species | |
| †Pulchrapollia gracilis (Dyke & Cooper, 2000) | |
Pulchrapollia is anextinct genus ofhalcyornithid bird from theEarly EoceneLondon Clay ofWalton-on-the-Naze, United Kingdom and theNanjemoy Formation ofVirginia, United States. The genus contains three species,Pulchrapollia gracilis,Pulchrapollia tenuipes andPulchrapollia eximia.
The holotype ofPulchrapollia was originally found in 1978 by a collector nearWalton-on-the-Naze in Bed A, a Ypresian sediment of the London Clay, a fossil-rich formation. The holotype, BMNH A 6207, consists of a partial skeleton including much of the legs and wings, as well as two vertebrae and miscellaneous indeterminate skeletal fragments.[1] Additional specimens from the London Clay at Walton-on-the-Naze have been collected, including NMS.Z.2021.40.64 in 1985 and NMS.Z.2021.40.65 in 1991, both type specimens for species ofPulchrapollia, by M. Daniels.[2] In 2016,Gerald Mayr tentatively referred several new specimens from the Nanjemoy Formation ofVirginia, United States toPulchrapollia without specific assignment.[3]
In 2000, BMNH A 6207 was described as the type speciesPulchrapollia gracilis and assigned to thePsittaciformes byDyke and Cooper. The generic name is from Latinpulchra, meaning "beautiful", and "Polly", a common English name given to parrots. The specific epithet is from the Latingracilis, meaning slender.[1] In 2023, Mayr and Kitchener describedPulchrapollia tenuipes based on NMS.Z.2021.40.65. The specific epithet is from the Latintenuis, meaning slender, andpes, meaning foot, referring to a slendertarsometatarsus. Also described wasPulchrapollia eximia, holotype NMS.Z.2021.40.64. The specific epithet is from the Latineximius, meaning extraordinary, and refers to the very good preservation of the type fossil.[2]
Pulchrapollia was a small bird, about the size of thered-fronted parakeet. Thecoracoid is long and slender and has a well-developed procoracoid process. The humerus and ulna are gracile, as is the humerus.[1] Like other halcyornithids,Pulchrapollia had zygodactyl feet, with two toes facing forward and two facing back on each foot.[4] The holotype ofPulchrapollia eximia preserves aneurocranium, which is much smaller than that in other halcyornithids; the neurocranium ofPseudasturides macrocephalus, a similarly-sized bird, is twice as large, and that ofHalcyornis toliapicus is also much larger, with correspondingly largerbrain. It is possible that this difference represents an increase in encephalisation among halcyornithids over time.[2]
Pulchrapollia is a member of theHalcyornithidae, a family of Eocene birds known from theearly Eocene of Europe and North America. Halcyornithids are regarded as basal relatives of both parrots and songbirds.[4]Pulchrapollia was initially described as a psittaciform stem-parrot, and indeed was regarded as distinct from the Halcyornithidae.[1] The affinities of the halcyornithids are currently not clear, but new data on other fossil birds close to Psittacopasseres such as theMesselasturidae are allowing for clarification of the position of these zygodactyl Eocene birds.[2]