Trogons (Trogoniformes) are the only group of birds with a heterodactyl foot, in which the second toe is permanently reversed.
Trogons and their close relatives, quetzals, are members a pantropically distributed order of birds consisting of a single family, the Trogonidae, which contains at least 43 species and 109 subspecies.
They are among the most colorful birds in the world: males are patterned with hues of iridescent green, blue, violet and purple above, and a bright red, yellow or orange abdomen; females have gray or brown plumage.
“Trogons are the only group of birds with a heterodactyl foot, in which the second toe is permanently reversed,” said Dr. Gerald Mayr from the Senckenberg Research Institute and Natural History Museum Frankfurt and his colleagues.
“These colorful birds are mainly insectivorous or frugivorous; they breed in tree holes and are able to dig their nesting cavities into rotten wood with their powerful beaks.”
“The living species occur in tropical or subtropical latitudes of Africa, Asia and the Americas, and trogons are particularly diversified in the New World, where most species and genera occur.”
“Trogons have a scant Paleogene fossil record,” the paleontologists added.
“The hitherto oldest member of the group is Septentrogon madseni from the Early Eocene (54.5 million years ago) Fur Formation in Denmark.”
“The oldest well-represented trogoniform specimens are from the latest early or earliest Middle Eocene ( 48 million years ago) of Messel in Germany.”
“This site yielded two articulated skeletons of Masillatrogon pumilio, a species that exhibits heterodactyl feet and was smaller than all living trogons.”
The newly-described fossil species already had the heterodactyl foot characterizing living trogons.
The bird had a much narrower and more gracile beak than living trogons, which denotes different ecological attributes of the ancient species.
Named Eotrogon stenorhynchus, it lived in what is now…
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