''Gurilynia'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

enantiornithine The Enantiornithes, also known as enantiornithines or enantiornitheans in literature, are a group of extinct avialans ("birds" in the broad sense), the most abundant and diverse group known from the Mesozoic era. Almost all retained teeth and cla ...

birds.Kurochkin, E.N. (1999) "A new large enantiornithid from the Late Cretaceous of Mongolia." In I. Darevskii and A. Averianov (editors), "Materials on the History of Fauna of Eurasia. Zoological Institute of the Russian Academy of Sciences, Saint-Petersburg" 277: 132–147. QL1 .A4253 v.277 1999 n Russian/ref> One species is known, ''G. nessovi''. It lived during the

Maastrichtian The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interval from ...

stage of the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...

period, between 70 and 66 mya. Clarke, Julia A., Norell, Mark A. (2004) "New Avialan Remains and a Review of the Late Cretaceous Nemegt Formation of Mongolia" "American Museum Novitates" Number 3447, 12pp. June 2, 2004 ''Gurilynia'' is known from fragmentary

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

s found at the Gurilyn Tsav locality of the

Nemegt Formation The Nemegt Formation (also known as Nemegtskaya Svita) is a geological formation in the Gobi Desert of Mongolia, dating to the Late Cretaceous. The formation consists of river channel sediments and contains fossils of fish, turtles, crocodilians, ...

in south Gobi,

Mongolia Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 million, ...

Description

The fossil material includes three partial bones. The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

is the

proximal Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position pro ...

end of a right

humerus The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a roun ...

, catalog number PIN 4499-12. This specimen indicates the largest Mongolian Mesozoic bird, with a length of , hip height of , and weight of . A

paratype In zoology and botany, a paratype is a specimen of an organism that helps define what the scientific name of a species and other taxon actually represents, but it is not the holotype (and in botany is also neither an isotype nor a syntype). Of ...

is the

distal Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position pro ...

end of a left humerus, catalog number PIN 4499-14. The last paratype is the shoulder end of a left

coracoid A coracoid (from Greek κόραξ, ''koraks'', raven) is a paired bone which is part of the shoulder assembly in all vertebrates except therian mammals (marsupials and placentals). In therian mammals (including humans), a coracoid process is prese ...

, catalog number PIN 4499-13. All three fossils are in the collection of the Paleontological Institute of the Russian Academy of Sciences. The material is depicted in the journal with both photographs and illustrations. The humeral head is around wide. The largest

from the

Early Cretaceous The Early Cretaceous ( geochronological name) or the Lower Cretaceous (chronostratigraphic name), is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 145 Ma to 100.5 Ma. Geology Pro ...

is ''

Pengornis ''Pengornis'' is the largest known enantiornithine bird from the Early Cretaceous of northeast China. The name derives from "Peng", which refers to a mythological bird from Chinese folklore, and "-ornis", which means bird in Greek. ''Pengorni ...

'', with a humeral head width of ."Insight into diversity, body size and morphological evolution from the largest Early Cretaceous enantiornithine bird" Zhonghe Zhou, Julia Clarke, Fucheng Zhang "Journal of Anatomy" (2008) 212, pp565–577. Kurochkin also mentions that "The additional distal portions of the ulna, radius, and carpometacarpus from the same beds also very probably belong to the Enantiornithes." This passage may describe PIN 4499-1, which was later assigned to ''

Teviornis ''Teviornis'' is a genus of extinct birds. One species has been described, ''T. gobiensis''. It lived in the Maastrichtian stage at the end of the Late Cretaceous period, some 70 million years ago. It is known from fossils collected from the Nem ...

''. Kurochkin also adds that ''G. nessovi'' demonstrates that there were large Enantiornithids in Central Asia as well as the Americas at the end of the Cretaceous.

References

{{Taxonbar, from=Q4163335 Euenantiornitheans Fossil taxa described in 1999 Late Cretaceous birds of Asia Nemegt fauna