''Hollanda'' 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 ...

of small ground birds known from fossils found in the Barun Goyot Formation of

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, ...

. Found at Khermeen Tsav, it dates from the late

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...

period ( Campanian stage), about 75 million years ago. Known only from partial hind limbs, ''Hollanda'' has long legs with an unusual configuration of the toes. These indicate that it was a fast-running ground bird, possibly similar to the modern Roadrunner.Bell, A.K., Chiappe, L.M., Erickson, G.M., Suzuki, S., Watabe, M., Barsbold, R. and Tsogtbaatar, K. (2010). "Description and ecologic analysis of ''Hollanda luceria'', a Late Cretaceous bird from the Gobi Desert (Mongolia)." ''Cretaceous Research'', 31(1): 16-26. Its relationships are uncertain. Some studies have found that it was an relatively advanced bird, a member of the

Ornithurae Ornithurae (meaning "bird tails" in Greek) is a natural group which includes the common ancestor of ''Ichthyornis'', ''Hesperornis'', and all modern birds as well as all other descendants of that common ancestor. Classification Ernst Haeckel coi ...

, related to birds like '' Ichthyornis''. Other studies have recovered it as a member of the primitive family

Songlingornithidae Songlingornithidae is a family of basal euornitheans from the Early Cretaceous of China. All known specimens come from the Jiufotang Formation and the Yixian Formation, dating to the early Barremian and Aptian ages, 125–120 million years ag ...

. A more expansive study found it as an

enantiornithean 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 ...

.Hartman, Scott; Mortimer, Mickey; Wahl, William R.; Lomax, Dean R.; Lippincott, Jessica; Lovelace, David M. (2019). "A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight". PeerJ. 7: e7247. . . . .Dinosaur Institute at the Natural History Museum of Los Angeles County project lead and researcher, Alyssa Bell, named the new species after the Holland family (donors to the project) and the rock band Lucero.

References

{{Taxonbar, from=Q2610970 Late Cretaceous birds of Asia Fossil taxa described in 2010 Prehistoric avialans