''Jabiru codorensis'' is an extinct species of

stork 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 ...

related to the extant

Jabiru The jabiru ( or ; ''Jabiru mycteria'') is a large stork found in the Americas from Mexico to Argentina, except west of the Andes. It sometimes wanders into the United States, usually in Texas, but has also been reported in Mississippi, Oklahoma ...

. It lived in what is now

Venezuela Venezuela, officially the Bolivarian Republic of Venezuela, is a country on the northern coast of South America, consisting of a continental landmass and many Federal Dependencies of Venezuela, islands and islets in the Caribbean Sea. It com ...

during the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Codore Formation, specifically the E1 Jebe Member. The

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

, AMU CURS 130–5, is a

tibiotarsus The tibiotarsus is the large bone between the femur and the tarsometatarsus in the leg of a bird. It is the fusion of the proximal part of the tarsus with the tibia. A similar structure also occurred in the Mesozoic Heterodontosauridae. These ...

lacking its proximal end. The second specimen,

paratype In zoology and botany, a paratype is a specimen of an organism that helps define what the scientific name of a species and other taxon actually represents, but it is not the holotype (and in botany is also neither an isotype (biology), isotype ...

(AMU CURS 130–5), a

tarsometatarsus The tarsometatarsus is a bone that is only found in the lower leg of birds and some non-avian dinosaurs. It is formed from the fusion of several bird bones found in other types of animals, and homologous to the mammalian tarsus (ankle bones) a ...

likewise lacks its proximal end and was found in association with the holotype specimen. Due to the proximity of the two specimens it is believed that they stem from the same individual. It was named by Stig Walsh and Rodolfo Sánchez in 2008. While examining the material, they initially thought the bones belonged to a

phorusrhacid Phorusrhacids, colloquially known as terror birds, are an extinct family of large carnivorous, mostly flightless birds that were among the largest apex predators in South America during the Cenozoic era. Their definitive fossil records range from ...

, a family of large

cursorial A cursorial organism is one that is adapted specifically to run. An animal can be considered cursorial if it has the ability to run fast (e.g. cheetah) or if it can keep a constant speed for a long distance (high endurance). "Cursorial" is often ...

predatory birds. Although fossil material of the genus ''Jabiru'' had been reported in the past, said remains have either been mentioned without source or were later regarded as belonging to the stork '' Ciconia maltha''. The

species name In taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, altho ...

was chosen to reflect the Codore Formation where the fossils had been found.

Description

Although morphologically similar to the extant

(''Jabiru mycteria''), this species differs from its relative through the narrower and shorter sulcus extensorius. It also possesses a pons supratendineus which protrudes at a shallower angle and an additional sulcus on the caudal surface of the tibiotarsus. The tarsometatarsus also differs from the modern Jabiru, having a deeper plantar sulcus and a more weakly developed ridge along the fossa supratrochlearis plantaris. The tibiotarsus is long and slender, growing more slender as it moves away from the proximal end before widening again at the

epiphysis An epiphysis (; : epiphyses) is one of the rounded ends or tips of a long bone that ossify from one or more secondary centers of ossification. Between the epiphysis and diaphysis (the long midsection of the long bone) lies the metaphysis, inc ...

at the distal end of the bone. The preserved portion of the bone is long, but taking into account the missing proximal end it may have reached a

total length Fish measurement is the measuring of individual fish and various parts of their anatomies, for data used in many areas of ichthyology, including taxonomy and fishery biology. Overall length Standard length (SL) is the length of a fish measured f ...

of . The front (cranial) surface of the

shaft Shaft may refer to: Rotating machine elements * Shaft (mechanical engineering), a rotating machine element used to transmit power * Line shaft, a power transmission system * Drive shaft, a shaft for transferring torque * Axle, a shaft around whi ...

is flattened, while the back takes on a more rounded shape. Due to fossilisation the bone is slightly compressed. The sulcus extensorius, a groove on the surface of the bone, is narrow but deep, making up 28% of the shaft's depth in some areas of the bone. The pons supratendineus emerges at a similar angle as in the

painted stork The painted stork (''Mycteria leucocephala'') is a large wader in the stork family. It is found in the wetlands of the plains of tropical Asia south of the Himalayas in the Indian Subcontinent and extending into Southeast Asia. Their distinctive ...

, but with sloping sides resembling modern jabirus and storks of the genus ''

Ephippiorhynchus '' Ephippiorhynchus'' is a small genus of storks. It contains two living species only, very large birds more than 140 cm tall with a 230–270 cm wingspan. Both are mainly black and white, with huge bills. The sexes of these species are ...

''. The intercondylar notch is deep and perfectly round, which identifies the bone as belonging to a stork. Both protrusions of the tibiotarsus that border this notch are equal in size with an oval outline, flattened surface and a prominent notch. In the fossil the distal caudal surface is flattened to such a degree that the transition to the lateral and medial surface of the bone is prominently angled. This trait is shared by only two other known storks, the modern Jabiru and the

black-necked stork The black-necked stork (''Ephippiorhynchus asiaticus'') is a tall long-necked wading bird in the stork family. It is a resident species across the Indian Subcontinent and Southeast Asia with a disjunct population in Australia. It lives in wetla ...

. There is also an additional depression on this surface, which is unlikely to be caused by

taphonomy Taphonomy is the study of how organisms decay and become fossilized or preserved in the paleontological record. The term ''taphonomy'' (from Greek language, Greek , 'burial' and , 'law') was introduced to paleontology in 1940 by Soviet scientis ...

given its presence on the least compressed part of the fossil, and not found in its modern relative. Much like the tibiotarsus, the tarsometatarsus is a slender bone of great length, exceeding the tibiotarsus with a preserved length of . However it would be shorter in life as it is calculated that the missing element only accounts for an additional . With the exception of the less pronounced cristae hypotarsi, what is preserved of the proximal end is similar to ''Jabiru mycteria''. The shaft of the bone is broader than in the bones of extant Jabirus, however this may be due to the deformation that the bone went through while fossilizing. Here too the sulcus extensorius is narrow and takes up 79% of the shaft's surface. This sulcus widens slightly towards its proximal most end. A prominent ridge is present on the plantar surface of the joints that connect the tarsometatarsus with the

metatarsals The metatarsal bones or metatarsus (: metatarsi) are a group of five long bones in the midfoot, located between the tarsal bones (which form the heel and the ankle) and the phalanges (toes). Lacking individual names, the metatarsal bones are nu ...

. It borders the also prominent fossa supratrochlearis plantaris and is much better-developed than in marabou storks as well as members of ''

Ciconia __NOTOC__ ''Ciconia'' ( ; ) is a genus of birds in the stork family. Six of the seven living species occur in the Old World, but the maguari stork has a South American range. In addition, fossils suggest that ''Ciconia'' storks were somewhat mo ...

'' and ''Ephippiorhynchus'', some of which even lack this feature entirely. However the ridge is not as broad as in ''Mycteria'' and ''Jabiru''. The known elements are almost identical to ''Jabiru mycteria'' in size, which are known to reach a height of and a

wingspan The wingspan (or just span) of a bird or an airplane is the distance from one wingtip to the opposite wingtip. For example, the Boeing 777–200 has a wingspan of , and a wandering albatross (''Diomedea exulans'') caught in 1965 had a wingsp ...

of .''CRC Handbook of Avian Body Masses, 2nd Edition'' by John B. Dunning Jr. (Editor). CRC Press (2008), .

Paleobiology

Modern Jabirus are widespread across South America, ranging from

Honduras Honduras, officially the Republic of Honduras, is a country in Central America. It is bordered to the west by Guatemala, to the southwest by El Salvador, to the southeast by Nicaragua, to the south by the Pacific Ocean at the Gulf of Fonseca, ...

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

with an isolated report indicating an animal that made it as far north as

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

. In ints native range Jabirus live in wetland environments and swamps, where they feed on a variety of small animals including reptiles, fish and various invertebrates. The El Jebe Member of the Codore Formation is thought to preserve similar conditions to those that Jabirus inhabit today, which, alongside the similar morphology, may indicate that ''Jabiru codorensis'' lead a similar lifestyle to its modern relative. During the Pliocene, the region was a floodplain with both slow moving meandering rivers in the west and a larger river in the central portion of the region.

References

{{Taxonbar, from=Q112245934 Ciconiidae Pliocene birds of South America Fossil taxa described in 2008 Fossils of Venezuela