''Xenerodiops'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

s, containing one species, ''Xenerodiops mycter''. Its

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 preserve ...

remains were found in

Egypt Egypt ( , ), officially the Arab Republic of Egypt, is a country spanning the Northeast Africa, northeast corner of Africa and Western Asia, southwest corner of Asia via the Sinai Peninsula. It is bordered by the Mediterranean Sea to northe ...

by Elwyn L. Simons and first formally described in 1987. It lived in the

Oligocene The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...

(about 33

million 1,000,000 (one million), or one thousand thousand, is the natural number following 999,999 and preceding 1,000,001. The word is derived from the early Italian ''millione'' (''milione'' in modern Italian), from ''mille'', "thousand", plus the ...

years ago). It has been placed in its own family, Xenerodiopidae; the alternative view is that this family is

synonymous A synonym is a word, morpheme, or phrase that means precisely or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are a ...

with Ardeidae, the herons.

Description

The only known

remains of this animal are an incomplete

beak The beak, bill, or rostrum is an external anatomical structure found mostly in birds, but also in turtles, non-avian dinosaurs and a few mammals. A beak is used for pecking, grasping, and holding (in probing for food, eating, manipulating and ...

(rostrum) and a left

humerus The humerus (; : humeri) 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 (bone), radius and ulna, and consists of three sections. The humeral upper extrem ...

, which allowed a reconstruction of its possible appearance. The dimensions had to be slightly larger than those of a current

heron Herons are long-legged, long-necked, freshwater and coastal birds in the family Ardeidae, with 75 recognised species, some of which are referred to as egrets or bitterns rather than herons. Members of the genus ''Botaurus'' are referred to as bi ...

, and its appearance was relatively different due to the strange beak which was rather short, heavy and curved upwards, different from that of any other form of heron according to Rasmussen et al. The

was stout enough to suggests that this animal was of a robust structure. The lifestyle of this mysterious bird is not clear: the rostrum was very mobile and it seems that the animal was able to exercise a powerful bite.

Taxonomy

When first described in 1987 as ''Xenerodiops mycter'', the species was placed in a new genus, ''Xenerodiops'', and a new family, Xenerodiopidae. The genus name is formed from the

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

''xenos'', stranger, ''erodios'', heron, and ''ops'', here meaning resemblance. The species name ''mycter'' is from the Greek ''mykter'', nose. Despite the scarcity of fossil remains, the describers considered this species to be related to the herons, family Ardeidae. At the time, herons were placed in the order

Ciconiiformes Storks are large, long-legged, long-necked wading birds with long, stout bills. They belong to the family Ciconiidae, and make up the order Ciconiiformes . Ciconiiformes previously included a number of other families, such as herons and ibise ...

, known to be paraphyletic. The order has since been split, with herons placed in Pelecaniformes. Jiří Mlíkovský compared ''X. mycter'' with '' Zeltornis ginsburgi'', found in

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

deposits in

Libya Libya, officially the State of Libya, is a country in the Maghreb region of North Africa. It borders the Mediterranean Sea to the north, Egypt to Egypt–Libya border, the east, Sudan to Libya–Sudan border, the southeast, Chad to Chad–L ...

. He considered that they might be the same species, although this could not be settled as they were described from different fossilized parts. However, he did synonymize the family Xenerodiopidae with Ardeidae, partly on the grounds that the unusually shaped rostrum was similar to those of other members of the subfamily Nycticoracinae.

Distribution and habitat

''Xenerodiops mycter'' was found in

, but may be the same species as one found in

. It lived in a

tropical The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's ax ...

climate Climate is the long-term weather pattern in a region, typically averaged over 30 years. More rigorously, it is the mean and variability of meteorological variables over a time spanning from months to millions of years. Some of the meteoro ...

, surrounded by

swamps A swamp is a forested wetland.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p. Swamps are considered to be transition zones because both land and water play a role in ...

References

{{Taxonbar, from=Q4021762 Pelecaniformes Prehistoric birds of Africa