Protodontopteryx

Protodontopteryx Temporal range: EarlyPaleocene,~
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	†Odontopterygiformes
Family:	†Pelagornithidae
Genus:	†Protodontopteryx Mayret al., 2019
Type species
†Protodontopteryx ruthae Mayr et al., 2019

Protodontopteryxis agenusofpelagornithid(pseudotooth bird) that lived inNew Zealandroughly 62 million years ago, during the earlyPaleoceneepoch. It contains one species,Protodontopteryx ruthae.Protodontopteryxis the smallest, oldest, and mostbasalpelagornithid discovered.

Discovery and naming

Theholotypespecimen ofProtodontopteryx ruthae,CM 2018.124.8,was collected in theCanterbury Regionof New Zealand on 11 November 2017 by Leigh Love. It is from the Mt Ellen Member of theWaipara Greensand.The specimen is a partial skeleton including the skull, portions of the limb bones, some vertebrae, and a wing phalanx. The latter two are in a separate block ofmatrixfrom the rest, and none of the bones are preserved in articulation; since there exists a possibility the fossil contains bones from two different individuals (and potentially different species), the authors specifically designate the skull as the holotype. Another specimen, CM 2018.124.9, was also referred toP. ruthae;it consists of theproximalend of a left humerus anddistalsections of?radius and?ulna, and was collected from the Mt Ellen Member in 2016 by Love.

In 2019,Protodontopteryx ruthaewasdescribedby Gerald Mayr, Vanesa L. De Pietri, Leigh Love, Al Mannering, and Richard Paul Scofield. Thegeneric namecombines theGreekproto( "first" ) withOdontopteryx,one of the earliest-coined names for a pelagornithid. Thespecific namehonors Ruth Love, the wife of the fossil's collector Leigh Love.

Description

With an estimatedwingspanof about 1 meter (3.3 feet),Protodontopteryxwas the size of an averagegull—much smaller than all post-Paleocene pelagornithids. It had a much stouter humerus than a typical pelagornithid, indicating it was less specialized toward sustained soaring.

The beak was similar in relative length to that of other pelagornithids, but was deeper at the base and therefore tapered more strongly toward the tip. The tip was more downcurved than in other pelagornithids. The external nostrils were larger than the very reduced nostrils of other pelagornithids, and were more similar in size and position to those ofalbatrosses.This suggestsProtodontopteryxwas less pelagic than later pelagornithids (many livingaequornitheanseabirds have reduced external nostrils to protect the nasal cavity against saltwater). Like other pelagornithids,Protodontopteryxhad tooth-like projections on its beak called pseudoteeth—though these were shorter and less sharply pointed than those of its relatives, and the small interspersed pseudoteeth seen on many other pelagornithids were absent.

Paleobiology

The short pseudoteeth ofProtodontopteryx,contrasted with the more fragile needle-like pseudoteeth of later pelagornithids, may indicate a dietary shift in the family's evolution:Protodontopteryxmay have been mainlypiscivorous,while later species foraged forsquidand othermolluscs.

Paleoecology

During the early Paleocene whenProtodontopteryxlived, New Zealand had a tropical climate with a sea temperature of about 25 degrees Celsius (77 degrees Fahrenheit).Other birds found in the Waipara Greensand include the earliest knowntropicbird(Clymenoptilon) and the earliest knownpenguins(WaimanuandMuriwaimanu).