Ypresiglaux

Last updated

Ypresiglaux
Temporal range: early Eocene,
54.6–55  Ma
Ꞓ
O
S
D
C
P
T
J
K
Pg
N
↓
Ypresiglaux michaeldanielsi holotype.jpg
Holotype fossil elements of Y. michaeldanielsi
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Strigiformes
Genus:† Ypresiglaux
Mayr & Kitchener, 2022
Type species
†Ypresiglaux michaeldanielsi
Mayr & Kitchener, 2022
Other species
  • †Y. gulottaiMayr & Kitchener, 2022
Synonyms

Ypresiglaux (meaning "Ypresian owl") is an extinct genus of strigiform bird from the Early Eocene London Clay Formation of Essex, United Kingdom and Nanjemoy Formation of Virginia, United States. The genus contains two species: Y. michaeldanielsi, known from a partial skeleton, and Y. gulottai, known from a distal tarsometatarsus. [1]

Contents

Discovery and naming

Cliffs near the type locality Cliff erosion at the Naze - geograph.org.uk - 724944.jpg
Cliffs near the type locality
Skull elements of Y. michaeldanielsi Ypresiglaux.jpg
Skull elements of Y. michaeldanielsi

Ypresiglaux was described in 2022 by German zoologist Gerald Mayr and British zoologist Andrew C. Kitchener. The generic name, "Ypresiglaux", combines a reference to the Ypresian-dated type locality with the Greek word "glaux," meaning "owl". The type species, Y. michaeldanielsi, was described on the basis of a partial skeleton collected in 1992. This specimen, NMS.Z.2021.40.26, which includes the mandible, vertebrae, pectoral girdle, wing bones, and a partial right leg, was designated as the holotype. NMS.Z.2021.40.27, an additional specimen collected in 1982, consists of the distal portion of the right femur, distal half of the right tarsometatarsus, and pedal phalanges. It was also referred to Y. michaeldanielsi. These fossils were discovered by Michael Daniels in layers of the London Clay Formation (Walton Member), dated to the early Ypresian, which is located near Walton-on-the-Naze in Essex, England. The specific name, "michaeldanielsi", honors Michael Daniels. Y. michaeldanielsi represents one of the most completely-known Palaeogene owls. [1]

Additional fossil material, consisting of a partial right femur, partial right tarsometatarsus, and pedal phalanges (specimen NMS.Z.2021.40.27) was also collected from the Walton Member of the London Clay Formation. Since the fossil material is slightly larger than overlapping bones of Y. michaeldanielsi, it is possible that it represents a female specimen of the latter, since sexual dimorphism has been consistently observed in owls. Some important differences between the bones suggest that they may represent a distinct species. However, due to the lack of morphological differences, the specimen could not be confidently placed beyond "Ypresiglaux sp." [1]

In 2016, Gerald Mayr described a distal right tarsometatarsus as belonging to a new species of the extinct owl genus Eostrix , E. gulottai. The holotype specimen, SMF Av 627, was discovered in layers of the Eocene (Ypresian)-dated Nanjemoy Formation (Potapaco Member) of Stafford County, Virginia, USA. In 2022, Mayr and Kitchener moved 'Eostrix' gulottai to the new genus Ypresiglaux as the new combination, Y. gulottai. The specific name honors Marco Gulotta, the discoverer of the specimen. [2] [1]

Description

Ypresiglaux was a very small owl. Y. michaeldanielsi was comparable in size to the Eurasian Pygmy Owl, which has a body mass of 50–77 grams. [1] Y. gulottai was even smaller, and represents the smallest known owl (extinct or extant). It is suggested that it likely had a diet comparable to the similarly sized extant long-whiskered owlet and elf owl, which primarily eat arthropods. [2]

It is likely that Ypresiglaux did not have the same degree of head rotational mobility as extant owls because of differences in the atlas and axis. Mayr and Kitchener (2022) further suggest that Ypresiglaux occupied a diurnal niche, contrary to extant owls, which are often nocturnal. [1] Preserved fossilized toe pad integument was observed on a piece of matrix collected with a pedal phalanx. A similar instance was seen in the holotype of the contemporary Lutavis . [3]

Classification

In their phylogenetic analyses, Mayr & Kitchener (2022) recovered Ypresiglaux in various positions within the Strigiformes. They stated that the discovery of additional fossil material could provide more insight into the exact phylogenetic relationships of Ypresiglaux. The cladogram below displays the results of two different phylogenetic analyses. [1]

See also

Related Research Articles

<i>Masillaraptor</i> Extinct genus of falcons

Masillaraptor is an extinct genus of masillaraptorid, a group of primitive falconiforms, from the Middle Eocene Messel Pit, Germany. It is a long-legged relative of the living falcons.

Eurofluvioviridavis is a genus of extinct primitive birds from the Middle Eocene Messel Pit, Germany. It contains a single species, Eurofluvioviridavis robustipes. It is related to Avolatavis and Vastanavis, other members of the family Vastanavidae.

Eostrix is a genus of extinct primitive owls in the family Protostrigidae, along with Oligostrix and Minerva. These owls date from the early Eocene of the United States, Europe, and Mongolia. They have been described based on fossil remains. The genus was created by Pierce Brodkorb in 1971 to place a fossil species known until that time as Protostrix mimica.

<i>Juncitarsus</i> Extinct genus of birds

Juncitarsus is an extinct genus of wading birds from the Eocene of the United States and Germany. Though previously considered a flamingo, it is likely a stem-flamingo, possibly a relative of the group which contains both flamingos and grebes (Mirandornithes).

<i>Septencoracias</i> Extinct genus of birds

Septencoracias is an extinct genus of bird related to modern rollers and other Coraciiformes such as kingfishers, bee-eaters, motmots, and todies. It contains two species, Septencoracias morsensis described in 2016, and S. simillimus, which was named in 2024. It was found in the Fur Formation of Denmark, dating back to the Ypresian of the Lower Eocene Epoch, about 54 million years ago. Septencoracias is one of the earliest known members of Coraciiformes, lending insight into the earliest radiation of this group.

<span class="mw-page-title-main">Messelasturidae</span> Extinct family of birds

Messelasturidae is an extinct family of birds known from the Eocene of North America and Europe. Their morphology is a mosaic that in some aspects are very similar to modern hawks and falcons, but in others are more similar to parrots. Initially interpreted as stem-owls, more recent studies have suggested a closer relationship to parrots and passerines. Their ecology is enigmatic.

<span class="mw-page-title-main">Halcyornithidae</span> Extinct family of birds

Halcyornithidae is an extinct family of telluravian birds thought to be related to the Psittaciformes (parrots), Passeriformes (songbirds), and to the extinct Messelasturidae. Halcyornithids have been found in various Eocene formations in Europe and North America. Widespread and diverse in the Early Eocene of North America and Europe, halcyornithids are not found in locales later than the Middle Eocene. Halcyornithids were small, arboreal birds with zygodactyl feet, with two toes facing forwards and two facing back, a trait shared with other tree-dwelling families of Eocene birds like the Zygodactylidae and the messelasturids. The skull of halcyornithids features a ridge of bone above the eye called the supraorbital process, similar to birds of prey. The relationships of the halcyornithids to other birds remain uncertain. Halcyornithids have been proposed as relatives to owls and as a lineage closer to parrots than to songbirds. Most recently, halcyornithids have been identified as the sister group of the clade including parrots and songbirds. It is also possible that Halcyornithidae is paraphyletic with respect to the Messelasturidae.

Morsoravis is an extinct genus of neoavian bird from the Early Eocene Fur Formation of Denmark. It contains a single named species, Morsoravis sedilis. Fossils of Morsoravis have also been found in the Green River Formation of Wyoming and possibly the Nanjemoy Formation of Virginia.

<i>Allgoviachen</i> Extinct genus of birds

Allgoviachen is an extinct genus of anatid bird from the Late Miocene (Tortonian) Hammerschmiede clay pits of Bavaria, Germany. The genus contains a single species, A. tortonica, known from bones belonging to the left leg.

Danielsraptor is an extinct genus of masillaraptorid bird from the Early Eocene (Ypresian) Walton Member of the London Clay Formation in Essex, United Kingdom. The genus contains a single species, D. phorusrhacoides, known from a partial skeleton.

Nasidytes is an extinct genus of loon (Gaviiformes) that lived during the early Eocene in what is now Great Britain. It contains a single species, N. ypresianus. Nasidytes is the earliest unambiguously identified loon in the fossil record.

<i>Tonsala</i> Extinct genus of Plotopteridae

Tonsala is an extinct genus of Plotopteridae, a family of flightless seabird similar in biology with penguins, but more closely related to modern cormorants. The genus is known from terrains dated from the Late Oligocene of the State of Washington and Japan.

<i>Lutavis</i> Extinct genus of birds

Lutavis is an extinct genus of potentially afroavian bird from the Early Eocene London Clay Formation of Essex, United Kingdom. The genus contains a single species, L. platypelvis, known from a partial skeleton.

<i>Waltonavis</i> Extinct genus of birds

Waltonavis is an extinct genus of potentially leptosomiform bird from the Early Eocene London Clay Formation of Essex, United Kingdom. The genus contains two species: W. paraleptosomus and W. danielsi, both known from partial skeletons.

<i>Psittacomimus</i> Extinct genus of psittacopedid birds

Psittacomimus is an extinct genus of psittacopedid bird from the Early Eocene London Clay Formation of Essex, United Kingdom. The genus contains a single species, P. eos, known from a partial skeleton.

<i>Minutornis</i> Extinct genus of parapasserine birds

Minutornis is an extinct genus of parapasserine bird from the Early Eocene London Clay Formation of Essex, United Kingdom. The genus contains a single species, M. primoscenoides, known from a fragmentary skeleton.

Charadriisimilis is an extinct genus of charadriiform birds from the Early Eocene (Ypresian) London Clay of Walton-on-the-Naze, United Kingdom. The genus contains a single species, Charadriisimilis essexensis, known from partial postcranial remains.

Pulchrapollia is an extinct genus of halcyornithid bird from the Early Eocene London Clay of Walton-on-the-Naze, United Kingdom and the Nanjemoy Formation of Virginia, United States. The genus contains three species, Pulchrapollia gracilis, Pulchrapollia tenuipes and Pulchrapollia eximia.

Pseudasturides is an extinct genus of halcyornithid bird from the Middle Eocene Messel pit in Hesse, Germany, and possibly the Isle of Sheppey, United Kingdom. The genus is represented by a single species, Pseudasturides macrocephalus.

Sororavis is an extinct genus of bird from the Early Eocene London Clay of Walton-on-the-Naze, United Kingdom. It contains a single named species, Sororavis solitarius. It is a member of the Morsoravidae.

References

  1. 1 2 3 4 5 6 7 Mayr, Gerald; Kitchener, Andrew C. (2022). "Early Eocene fossil illuminates the ancestral (diurnal) ecomorphology of owls and documents a mosaic evolution of the strigiform body plan". Ibis . 165: 231–247. doi: 10.1111/ibi.13125 . ISSN   0019-1019. S2CID   251455832.
  2. 1 2 Mayr, Gerald (2016). "The world's smallest owl, the earliest unambiguous charadriiform bird, and other avian remains from the early Eocene Nanjemoy Formation of Virginia (USA)". PalZ. 90 (4): 747–763. doi:10.1007/s12542-016-0330-8. S2CID   89558571.
  3. ↑ Mayr, Gerald; Kitchener, Andrew C. (30 November 2022). "New species from the early Eocene London Clay suggest an undetected early Eocene diversity of the Leptosomiformes, an avian clade that includes a living fossil from Madagascar". Palaeobiodiversity and Palaeoenvironments. 103 (3): 585–608. doi: 10.1007/s12549-022-00560-0 . ISSN   1867-1594. S2CID   254333827.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.