Phorusrhacidae

Andalgalornis

• South America
• Florida
• Antarctic
• Morocco

The Phorusrhacidae (often referred to in popular publications " terror birds " ) were large to very large, ground-dwelling and mostly flightless birds, whose fossils have been found mainly in South America. They took during the Paleogene and Neogene in South America, the role of top predators. The only extant birds, which are more closely related to them, are the South American Seriemas ( Cariamidae ). Ten genera and 25 species have been described. The oldest type is Paleopsilopterus itaboraiensis from the middle Paleocene ( Itaboraium ) Rio de Janeiro ( Brazil).

History and distribution of the family

The first Phorusrhacide Phorusrhacos longissimus was described in 1887 by the Argentine naturalist Florentino Ameghino by a Fund in the Argentine province of Santa Cruz. Later discoveries were made in other parts of Argentina, Bolivia and Brazil. From the Antarctic King George Island, two single, three-toed footprints 18 cm long from the time of 55 million years ago are known to be associated with either a Phorusrhaciden or a flightless bird. In addition, old layers was found on the island of Seymour the front part of a Phorusrhacoidenschnabels in 40 million years. Also from the Aquitaine Basin in France was reported with the 38-35 million year old Ameghinornis a Phorusrhacoide, who was only as big as a Seriema and apparently could still fly. However, close Alvarenga and Courtier (2003), this finding from the group of Phorusrhacidae from, and the family in this view contains only taxa from South America and Titanis walleri from the Upper Pliocene and Lower Pleistocene of North America. Today Ameghinornis and his relatives are asked the Ameghinornithidae in a separate family. 2011, the genus Lavocatavis been described in terms of a single femur, a Phorusrhacide from the early or middle Eocene of Morocco.

With the emergence of the Isthmus of Panama, that is, the formation of a land bridge between North and South America, the Phorusrhaciden therefore spread out to North America. As a stratigraphically youngest Fund was long the already mentioned 2.5 to 1.5 million years old Titanis walleri from North Florida. 2010 published a research group led by Herculano Alvarenga Phorusrhaciden residues from Uruguay who have an absolute age of 17,620 ± 100 years. This corresponds to chronostratigraphic the uppermost Pleistocene.

Features

Phorusrhaciden had a strong hull, a high, fitted to carnal food bill, a relatively long neck and long, muscular hind legs. Your stub wings are likely in most species have only served to maintain balance during the race. The flightless animals reached a body weight of about 45 to 350 kg, were one to three meters high and reached speeds of over 50 km / h

Way of life

The Phorusrhaciden took in South America, along with the flesh-eating mammals of the order Sparassodonta bag and terrestrial crocodiles Sebecidae the family the role of the missing here carnivores ( Carnivora ). While the other two groups, however, were rather slow, most of the terror birds specialized on fast prey in front of 27 million years, becoming increasingly open dry forests and savannas of South America. At the same time her gigantism began. Five million years ago, they had the predatory marsupial displaced completely from the savannahs. The larger species could kill with kicks prey of the size of an antelope. During an attack, the birds also used her head with large beak like an ax. Instead of getting wound up in the sacrifice, they put fast and accurate blows. There were, however clumsily built and slow terror birds, which probably fed on carrion. In South America, Phorusrhaciden died out at the end of the Pliocene. Very little is known about the cause of their extinction. It is believed that the Phorusrhaciden the new immigrant saber-toothed cats ( Machairodontinae ) and dogs ( Canidae ) were no match.

Outer systematics

As obvious carnivore birds Phorusrhaciden were first put to the birds of prey shortly after their discovery. But back in 1899 could prove Museum in London that is related to the still living in South American savannas Seriemas ( Cariamidae ) Charles W. Andrews by the British. Other close relatives are extinct families Bathornithidae from North America and the Idiornithidae from Europe. Both groups lived from Eocene to early Oligocene. All four families were traditionally made in the order of the Gruiformes ( Gruiformes ), and summarized here in a superfamily Cariamoidea or subordination Cariamae. As newer, stand on comparative DNA sequence analyzes supporting research, the monophyly of the crane -like in question and see the Seriemas out of order, and the affiliation of the Phorusrhacidae to the crane -like is now doubtful, and in more recent publications they are together with the Seriemas the order Cariamiformes assigned.

Inside systematics

The Phorusrhacidae after Alvarenga and Courtier (2003) divided into five subfamilies, 14 genera and 18 species. Their greatest diversity they reached during the Lower Miocene.

Subfamily Physornithinae

To subfamily Physornithinae are large to very large species. The birds had a heavy body, short legs and large beaks and may have been scavengers. Fossils from this group are 27-17 million years old.

• Genus Paraphysornis (Upper Oligocene / Lower Miocene of São Paulo, Brazil)
• Genus Physornis ( Intermediate to Upper Oligocene of Santa Cruz, Argentina)

Subfamily Phorusrhacinae

To subfamily Phorusrhacinae include medium-sized to very large species, up to a height of 2 to 3 meters. There were fast predators. Fossils from this group are 27-3 million years old.

• Genus Devincenzia (Upper Miocene to Lower Pliocene of Northeast Argentina and Arroyo novel, Uruguay)
• Genus Kelenken ( Middle Miocene of Río Negro, Argentina (currently the largest known Phorusrhacid ) )
• Genus Phorusrhacos (Lower than average Miocene )
• Genus Titanis ( Pliocene )

Subfamily Patagornithinae

To subfamily Patagornithinae include high medium large species, about 1.5 meters.

• Genus Patagornis (Lower than average Miocene of Santa Cruz, Argentina) including Morenomerceraria, Palaeociconia, Tolmodus
• Genus Andrewsornis ( Intermediate to Upper Oligocene of southern Argentina )
• Genus Andalgalornis (Upper Miocene to Lower Pliocene )

Subfamily Psilopterinae

To subfamily Psilopterinae include the smallest species, up to a height of about one meter. They had possibly retains a residual ability to fly. Fossils from this group are 63-3 million years old. The smallest known terror bird Psilopterus lemoinei belongs to this subfamily. He was as tall as a harpy and 8 kg.

• Genus Psilopterus ( Middle Oligocene to Upper Miocene of South and Ostargentinien )
• Genus Procariama (Upper Miocene to Lower Pliocene of Catamarca, Argentina)
• Genus Paleopsilopterus ( Middle Paleocene of Itaboraí, Brazil)

Subfamily Mesembriornithinae

The subfamily contains two Mesembriornithinae about 1 to 1.5 meters high, medium-sized species.

• Genus Mesembriornis (Upper Miocene to Upper Pliocene )

The described until 2011 North African genus Lavocatavis is not assigned to any subfamily. Originally belonged Physornis and Paraphysornis together mt Brontornis to the subfamily Brontornithinae. However, a revision of the genus Brontornis from the year 2007 showed a closer relationship with the geese birds, whereupon Brontornis will be made ​​on the basis of this group and the new subfamily Physornithinae the terror birds were introduced.