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Holbotia, enantiornithine bird from Early Cretaceous of Mongolia now official

Ben Creisler

A new paper that officially publishes the name Holbotia, which has
been cited at various times since 1982:

Holbotia ponomarenkoi

Nikita V. Zelenkov & Alexander O. Averianov (2015)
A historical specimen of enantiornithine bird from the Early
Cretaceous of Mongolia representing a new taxon with a specialized
neck morphology.
Journal of Systematic Palaeontology (advance online publication)

We describe Holbotia ponomarenkoi gen. et sp. nov., the first
articulated specimen of an enantiornithine bird from Mongolia,
unearthed in 1977 from Early Cretaceous deposits and formerly thought
to be a pterosaur. The specimen shows a series of morphological
details that are either unique to the new taxon or very poorly known
for Enantiornithes. A previously unobserved specialized cervical
morphology, the development of a crest on the caudal surface of the
distal tibia, and the presence of unusually widely spaced small teeth
in the lower jaw are unique features of Holbotia. The results of a
phylogenetic analysis indicate that Holbotia is more closely related
to the Late Cretaceous edentulous Gobipteryx than to the Early
Cretaceous enantiornithines with reduced dentition (Longipterygidae),
which implies a different evolutionary pathway for the loss of teeth
in Enantiornithes, as compared with Ornithuromorpha. The only
preserved cervical vertebra of Holbotia ponomarenkoi displays partly
ventrally facing prezygapophyseal articular surfaces, otherwise found
only in the darters (Anhingidae), which implies an unusually increased
degree of neck mobility. Morphology of the palate, described in detail
for an Early Cretaceous enantiornithine bird for the first time, is
roughly similar to that of Archaeopteryx and non-avian paravians. It
shows that the evolution of specialized rostral morphology in Early
Cretaceous enantiornithines was possible with retention of the
primitive palatal structure, in contrast to modern birds (Neornithes),
where the diversification of skull types was coupled with the
evolution of several types of palate.