Thomas pygmy anteater
| Thomas pygmy anteater | ||||||||||||
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| Cyclopes thomasi | ||||||||||||
| Miranda , Casali , Perini , Machado & Santos , 2017 |
The Thomas pygmy anteater ( Cyclopes thomasi ) is a species of mammal belonging to the genus of the pygmy anteater . Their range covers the western part of the Amazon basin in western Brazil and central Peru . In their outward appearance, the animals are characterized by an orange to reddish-brown back fur and a weak central stripe on the belly. The way of life is hardly explored. The species was introduced in 2017. The first description was preceded by genetic and morphological studies that refuted the original view that all pygmy anteaters could be assigned to one species.
description
Habitus
The Thomas pygmy anteater is a representative of the pygmy anteater. Information on body size and weight is not available. In all dwarf anteaters, the tail is longer than the rest of the body and can be used as a grasping organ . The limbs end in two rays on the hands and in four rays on the feet, each with a strong claw. The back of the Thomas dwarf anteater has a distinct orange to reddish brown tint, the underside is more yellowish, while the legs and tail are gray. On the abdomen there is an indistinct, little developed dark stripe along the center line of the body, but there is no corresponding stripe on the back. In this feature, the kind that in similar Bolivia occurring Bolivia silky anteater ( Cyclopes Catellus ), whose belly strips but clear and whose legs are rather yellowish. The reddish pygmy anteater ( Cyclopes rufus ), which is widespread in southwestern Brazil , also has a reddish-brown back coloration, but it lacks noticeable stripes. As with almost all dwarf anteaters, the hair does not have a medullary canal.
Skull features
As with all dwarf anteaters, the skull is strongly arched at the forehead line and dented at the base. There is no concave indentation in the area of the frontal and nasal bones . The lateral bone sutures between the nasal bone and the upper jaw do not run parallel to each other, but diverge forward. There is only brief contact between the frontal bone and the upper jaw. The suture that connects the frontal bone to the parietal bone shows a triangular shape. The external auditory canal at the base of the skull is oriented forward. In addition, the tympanic membrane is not overlaid by the wing bone .
distribution
The Thomas pygmy anteater is endemic to South America . The representative of the dwarf anteater is common in the western Amazon basin . Evidence of the species is available from the western Brazilian state of Acre and from the central Peruvian regions of Pasco and Ucayali . The northern limit of the deposit is found on the Rio Juruá , the southern limit on the Río Ucayali . The eastern border is not exactly known, but should coincide with the Rio Madeira .
Way of life
The way of life of the Thomas dwarf anteater has hardly been studied so far. In general, pygmy anteaters are arboreal , they are solitary and nocturnal. The preferred food consists of state-forming insects ( myrmecophag ).
Systematics
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Internal systematics of pygmy anteaters according to Miranda et al. 2017
No genetic data are yet available for Cyclopes catellus |
The Thomas pygmy anteater is a species from the genus of the pygmy anteater ( Cyclopes ), which, according to molecular genetic studies from 2017, contains a further six species. The genus is currently the only member of the thus monotypical family of Cyclopedidae within the suborder of the anteaters (Vermilingua). The Cyclopedidae are regarded as the sister group of the Myrmecophagidae , the latter grouping the other anteaters together with the genera Myrmecophaga and Tamandua . The dwarf anteaters are the smallest representatives of the anteaters. In contrast to the members of the Myrmecophagidae, they are completely adapted to tree life. The reddish dwarf anteater is considered to be the sister species of the Thomas dwarf ant . According to the genetic analyzes, both species form a separate clade within the genus Cyclopes , which stands opposite the other pygmy anteaters. Their separation from the line with the other dwarf anteaters took place in the Middle Miocene about 10.3 million years ago. The splitting of the clade into Cyclopes rufus and Cyclopes thomasi dates back to the Upper Pliocene about 3.4 million years ago. The separate position of the two species as well as the high age of differentiation could already be recognized in earlier analyzes. Possibly both are related to the stronger elevation of the Andes at this time. This resulted in a stronger sediment transport to the western Amazon region, which favored the conversion of the former swampy landscape into a drier forest area.
The first scientific description of the Thomas dwarf anteater was made in 2017 by a research group led by Flávia R. Miranda . It was preceded by extensive genetic and morphological studies on pygmy anteaters from the entire range. Originally, all representatives of the genus Cyclopes were considered to belong to one species, Cyclopes didactylus . The animals of the western and southwestern Amazon basins represented the subspecies Cyclopes didactylus ida and Cyclopes didactylus catellus . Both forms go back to Oldfield Thomas , the former was introduced by him in 1900, the latter in 1928. The analyzes by Miranda and fellow researchers, however, revealed a greater differentiation of the genus. The clear genetic and morphological differences as well as the high genetic age combined with the early phylogenetic separation of the southwestern and western populations prompted Miranda's team to view these as separate species, which resulted in the establishment of the species Cyclopes thomasi . The specific epithet thomasi honors Oldfield Thomas and his work on mammalogy , especially on the genus Cyclopes . The holotype consists of a full-grown female that was collected from Porto Walter in the Brazilian state of Acre in 1985 . The region represents the type area of the species.
Threat and protection
The Thomas pygmy anteater is not currently listed on the IUCN . The environmental protection organization regards the total population of dwarf anteaters as "not endangered" ( least concern ). However, local individual populations can be threatened by the deforestation of the tropical rainforests .
literature
- Flávia R. Miranda, Daniel M. Casali, Fernando A. Perini, Fabio A. Machado and Fabrício R. Santos: Taxonomic review of the genus Cyclopes Gray, 1821 (Xenarthra: Pilosa), with the revalidation and description of new species. Zoological Journal of the Linnean Society 20, 2017, pp. 1–35 doi: 10.1093 / zoolinnean / zlx079
- Flávia R. Miranda: Cyclopedidae (Silky anteaters). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 8: Insectivores, Sloths and Colugos. Lynx Edicions, Barcelona 2018, pp. 92-102 (p. 101) ISBN 978-84-16728-08-4
Individual evidence
- ↑ a b c Virginia Hayssen, Flávia Miranda and Bret Pasch: Cyclopes didactylus (Pilosa: Cyclopedidae). Mammalian Species 44 (1), 2012, pp. 51-58
- ↑ a b c d e f Flávia R. Miranda, Daniel M. Casali, Fernando A. Perini, Fabio A. Machado and Fabrício R. Santos: Taxonomic review of the genus Cyclopes Gray, 1821 (Xenarthra: Pilosa), with the revalidation and description of new species. Zoological Journal of the Linnean Society 20, 2017, pp. 1-35
- ↑ a b c Flávia R. Miranda: Cyclopedidae (Silky anteaters). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 8: Insectivores, Sloths and Colugos. Lynx Edicions, Barcelona 2018, pp. 92-102 (p. 101) ISBN 978-84-16728-08-4
- ^ A b c Alfred L. Gardner: Suborder Vermilingua Illiger, 1811. in: Alfred L. Gardner (ed.): Mammals of South America, Volume 1: Marsupials, Xenarthrans, Shrews, and Bats. University of Chicago Press, 2008, pp. 168-178
- Jump up ↑ Raphael Teodoro Franciscani Coimbra, Flávia Regina Miranda, Camila Clozato Lara, Marco Antônio Alves Schetino and Fabrício Rodrigues dos Santos: Phylogeographic history of South American populations of the silky anteater Cyclopes didactylus (Pilosa: Cyclopedidae). Genetics and Molecular Biology 40 (1), 2017, pp. 40-49 doi: 10.1590 / 1678-4685-GMB-2016-0040
- ↑ Oldfield Thomas: Descriptions of new rodents from western South America. Annals and Magazine of Natural History 6, 1999, pp. 294-302 ( [1] )
- ↑ Oldfield Thomas: The Godman Thomas expedition to Peru. VIII. On mammals obtained by Mr. Hendee at Pebas and Iquitos, upper Amazons. Annals and Magazine of Natural History 2, 1928, pp. 285-294
- ↑ Flávia Miranda and DA Meritt Jr .: Cyclopes didactylus. The IUCN Red List of Threatened Species 2014. e.T6019A47440020 ( [2] ), last accessed on January 6, 2018