''Chunga incerta'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of cariamid

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...

which inhabited the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58Southern Cone The Southern Cone ( es, Cono Sur, pt, Cone Sul) is a geographical and cultural subregion composed of the southernmost areas of South America, mostly south of the Tropic of Capricorn. Traditionally, it covers Argentina, Chile, and Uruguay, bou ...

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

. It belongs to the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

'' Chunga'', today only represented by one species, '' Chunga burmeisteri.''

History of discovery

This species was originally described in

1974 Major events in 1974 include the aftermath of the 1973 oil crisis and the resignation of United States President Richard Nixon following the Watergate scandal. In the Middle East, the aftermath of the 1973 Yom Kippur War determined politics; f ...

Argentinian Argentines (mistakenly translated Argentineans in the past; in Spanish (masculine) or ( feminine)) are people identified with the country of Argentina. This connection may be residential, legal, historical or cultural. For most Argentines, ...

paleontologist Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ...

Eduardo Pedro Tonni.Tonni, E. P. (1974). A new cariamid (Aves, Gruiformes) from the Upper Pliocene of Buenos Aires province. Ameghiniana 11 (4): 366-372. Buenos Aires. The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

is MLP 71-VII-5-1, the distal end of a tibiotarsus. MLP 71-VII-5-2 and MLP 71-VII-5-4 were also collected. These are fragmentary remains of tibiotarsus and tarsometatarsus. All of them were deposited in the collection of the museo de ciencias naturales of

La Plata La Plata () is the capital city of Buenos Aires Province, Argentina. According to the , it has a population of 654,324 and its metropolitan area, the Greater La Plata, has 787,294 inhabitants. It is located 9 kilometers (6 miles) inland from th ...

, which belongs to the Faculty of Natural Sciences and Museum of the

Universidad Nacional de La Plata The La Plata National University ( es, Universidad Nacional de La Plata, UNLP) is one of the most important Argentine national universities and the biggest one situated in the city of La Plata, capital of Buenos Aires Province. It has over 90, ...

(UNLP). The type locality of ''C. incerta'' is the Monte Hermoso Formation, in the Partido de Monte Hermoso,

Buenos Aires Buenos Aires ( or ; ), officially the Autonomous City of Buenos Aires ( es, link=no, Ciudad Autónoma de Buenos Aires), is the capital and primate city of Argentina. The city is located on the western shore of the Río de la Plata, on South ...

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

. The postulated age for the bearing stratum is

Late Pliocene Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, ...

, during the

Montehermosan The Montehermosan age is a period of geologic time (6.8–4.0 Ma) within the Miocene and Pliocene epochs of the Neogene used more specifically with South American Land Mammal Ages. It follows the Huayquerian and precedes the Chapadmalalan The C ...

Chapadmalalan The Chapadmalalan age is a period of geologic time (4.0–3.0 Ma) within the Pliocene epoch of the Neogene used more specifically with South American Land Mammal Ages. It follows the Montehermosan and precedes the Uquian age. Fossil content F ...

South American land mammal ages The South American land mammal ages (SALMA) establish a geologic timescale for prehistoric South American fauna beginning 64.5 Ma during the Paleocene and continuing through to the Late Pleistocene (0.011 Ma). These periods are referred to as age ...

, with an approximate age of 3 mya.

Description

Since ''Chunga incerta'' is known from little more than a tibiotarsus, little can be inferred of its anatomy. Nevertheless, its mass has been estimated at 1.95 kg, similar to that of the present-day

red-legged seriema The red-legged seriema (''Cariama cristata''), also known as the crested cariama and crested seriema, is a mostly predatory terrestrial bird in the seriema family ( Cariamidae), included in the Gruiformes in the old paraphyletic circumscription ...

Distribution

The only living member of the genus '' Chunga'', '' Chunga burmeisteri'', inhabits dry environments, such as

savannah A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) ecosystem characterised by the trees being sufficiently widely spaced so that the Canopy (forest), canopy does not close. The open canopy allows sufficient light to rea ...

scrubland Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominance (ecology), dominated by shrubs, often also including grasses, Herbaceous plant, herbs, and geophytes. Shrubland may either occur naturally or ...

and

dry forest Dry or dryness most often refers to: * Lack of rainfall, which may refer to **Arid regions **Drought * Dry or dry area, relating to legal prohibition of selling, serving, or imbibing alcoholic beverages * Dry humor, deadpan * Dryness (medical) ...

. The presence of ''Chunga incerta'' in an area where the genus does not currently inhabit indicates that in the past it had a more southern and eastern austral distribution, probably accompanying different ecological conditions in that area, with warmer temperatures than those currently found in the area.Tambussi, C. P. (1995). Las Aves. In: Alberdi, M., Leone, G. and Tonni, E. eds. Biological and climatic evolution of the Pampean Region during the last five million years. A correlation test with the western Mediterranean. Ch.7: 143-162. Monographs of the National Museum of Natural Sciences, CSIC, Madrid.

References

{{Taxonbar, from=Q25406201 Pliocene birds Birds of Argentina Extinct birds of South America incerta Fossil taxa described in 1974