Silky anteater

Species of mammals related to sloths and armadillosTemplate:SHORTDESC:Species of mammals related to sloths and armadillos

The **silky anteater**, also known as the **pygmy anteater**, has traditionally been considered a single species of anteater, *Cyclopes didactylus*, in the genus *Cyclopes*, the only living genus in the family Cyclopedidae. Found in southern Mexico, and Central and South America, it is the smallest of all known anteaters. It has nocturnal habits and appears to be completely arboreal; its hind feet are highly modified for climbing.

A taxonomic review in 2017, including both molecular and morphological evidence, found that *Cyclopes* may actually comprise at least seven species. The only known extinct cyclopedid species is *Palaeomyrmidon incomtus*, from the Late Miocene (c. 7 to 9 million years ago) of modern-day Argentina.

## Description

Silky anteaters are the smallest living anteaters, and have proportionately shorter faces and larger crania than other species. Adults have a total length ranging from 36 to 45 cm (14 to 18 in), including a tail 17 to 24 cm (6.7 to 9.4 in) long, and weigh from 175 to 400 g (6.2 to 14.1 oz). They have dense and soft fur, which ranges from grey to yellowish in color, with a silvery sheen. Many subspecies have darker, often brownish, streaks, and paler underparts or limbs. The eyes are black, and the soles of the feet are red.

The scientific name translates roughly as "two-toed circle-foot", and refers to the presence of two claws on the fore feet, and their ability to almost encircle a branch to which the animal is clinging. The claws are present on the second and third toes, with the latter being much the larger. The fourth toe is very small, and lacks a claw, while the other two toes are vestigial or absent, and are not visible externally. The hind feet have four toes of equal length, each with long claws, and a vestigial hallux that is not externally visible. The ribs are broad and flat, overlapping to form an internal armoured casing that protects the chest.

They have partially prehensile tails.

## Distribution and habitat

Silky anteaters are found from Oaxaca and southern Veracruz in Mexico, through Central America (except El Salvador), and south to Ecuador, and northern Peru, Bolivia, and Brazil. A distinct population is found in the northern Atlantic Forest of eastern Brazil. Silky anteaters are also found on the island of Trinidad. They inhabit a range of different forest types, including semi-deciduous, tropical evergreen, and mangrove forests, from sea level to 1,500 m (4,900 ft).

## Systematics

Silky anteaters form the sister clade to the myrmecophagid anteaters, together forming Vermilingua. Vermilingua is a sister clade to sloths (Folivora), together forming Pilosa.

Until a detailed taxonomic review in 2017, seven subspecies of *C. didactylus* were recognized.

* *C. d. didactylus* Linnaeus, 1758 - the Guyanas, eastern Venezuela, Trinidad, Atlantic Forest
* *C. d. catellus* Thomas, 1928 - northern Bolivia, southeastern Peru, western Brazil
* *C. d. dorsalis* Gray, 1865 - extreme southern Mexico, Central America, northern Colombia
* *C. d. eva* Thomas, 1902 - western Ecuador, southwestern Colombia
* *C. d. ida*, Thomas, 1900 - western Brazil, eastern Ecuador and Peru
* *C. d. melini* Lönnberg, 1928 - northern Brazil, eastern Colombia
* *C. d. mexicanus* Hollister, 1914 - southern Mexico

The 2017 review suggests that four of these subspecies deserve to be recognized as species, while the others are synonyms. It also described three new species of silky anteater.

* *C. didactylus* (Linnaeus, 1758) (synonym: *C. d. melini*) - the Guyanas, eastern Venezuela, Trinidad, Atlantic Forest and northern Brazil
* *C. catellus* Thomas, 1928 - Bolivia
* *C. dorsalis* (Gray, 1865) (synonyms: *C. d. eva* and *C. d. mexicanus*) - western Ecuador, southwestern to northern Colombia, Central America, southern Mexico
* *C. ida* Thomas, 1900 - western Brazil, eastern Ecuador, eastern Colombia and Peru
* *C. thomasi* Miranda et al., 2017 - Central Peru, extreme western Brazil (Acre)
* *C. rufus* Miranda et al., 2017 - Brazil (Rondônia)
* *C. xinguensis* Miranda et al., 2017 - Brazil, between the Madeira River and the Xingu River (Below the Amazon river)

## Behavior

Silky anteaters are nocturnal and arboreal, found in lowland rainforests with continuous canopy, where they can move to different places without the need to descend from trees. They can occur at fairly high densities of 0.77 individuals/ha, for example, in some areas.[*citation needed*] Females have smaller home ranges than males.

The silky anteater is a slow-moving animal and feeds mainly on ants, eating between 700 and 5,000 a day. Silky anteaters also feed on wasps and wasp pupae, attacking the wasp nests at night when the wasps are sluggish and unable to defend themselves. Sometimes, it also feeds on other insects, such as termites and small coccinellid beetles. The silky anteater defecates once a day. Some of those feces contain a large quantity of exoskeleton fragments of insects, indicating the silky anteater does not possess either chitinase or chitobiase, digestive enzymes found in insectivorous bats.

It is a solitary animal and gives birth to a single young, up to twice a year. The young are born already furred, and with a similar colour pattern to the adults. They begin to take solid food when they are about one-third of the adult mass. The young is usually placed inside a nest of dead leaves built in tree holes, and left for about eight hours each night.

Some authors suggest the silky anteater usually dwells in silk cotton trees (genus *Ceiba*). Because of its resemblance to the seed pod fibers of these trees, it can use the trees as camouflage and avoid attacks of predators such as hawks and, especially, harpy eagles. During the day, they typically sleep curled up in a ball. Although they are rarely seen in the forest, they can be found more easily when they are foraging on lianas at night.

When threatened, the silky anteater, like other anteaters, defends itself by standing on its hind legs and holding its fore feet close to its face so it can strike any animal that tries to get close with its sharp claws.

The silky anteater is a host of the acanthocephalan intestinal parasite *Gigantorhynchus echinodiscus*.

## See also

* Emmons, Louise H.; Feer, François (1997-09-02). *Neotropical rainforest mammals. A field guide* (2nd ed.). Chicago: University of Chicago Press. pp. 41–42. ISBN 978-0-226-20721-6. OCLC 44179508.
* Eisenberg, J.F. and Redford, K.H. 1999. "Mammals of the Neotropics, Volume 3: The Central Neotropics: Ecuador, Peru, Bolivia, Brazil". University of Chicago Press.

## References

1. ↑ Gardner, A.L. (2005). "Order Pilosa". In Wilson, D.E.; Reeder, D.M. *Mammal Species of the World: A Taxonomic and Geographic Reference* (3rd ed.). Johns Hopkins University Press. p. 102. ISBN 978-0-8018-8221-0. OCLC 62265494.
2. ↑ 2.0 2.1 Miranda, F.; Meritt, D.A.; Tirira, D.G.; Arteaga, M. (2014). "*Cyclopes didactylus*". *IUCN Red List of Threatened Species*. **2014**: e.T6019A47440020. doi:10.2305/IUCN.UK.2014-1.RLTS.T6019A47440020.en .
3. ↑ Linnæus, Carl (1758). *Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I* (in Latin) (10th ed.). Holmiæ: Laurentius Salvius. p. 35. Retrieved 23 November 2012.
4. ↑ 4.0 4.1 4.2 Miranda, F.R.; Casali, D.M.; Perini, F.A.; Machado, F.A.; Santos, F.R. (2017). "Taxonomic review of the genus *Cyclopes* Gray, 1821 (Xenarthra: Pilosa), with the revalidation and description of new species". *Zoological Journal of the Linnean Society*. **183** (3): 687–721. doi:10.1093/zoolinnean/zlx079.
5. ↑ McDonald, H. Gregory; Vizcaíno, Sergio Fabián; Bargo, M. Sazano (2008). "Skeletal anatomy and the fossil history of the Vermilingua". In Vizcaino, Sergío Fabian; Loughry, William J. *The Biology of the Xenarthra*. Gainesville, FL: University Press of Florida. pp. 64–78. ISBN 978-0813031651.
6. ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 6.7 Hayssen, V.; et al. (2012). "*Cyclopes didactylus* (Pilosa: Cyclopedidae)". *Mammalian Species*. **44** (1): 51–58. doi:10.1644/895.1 .
7. ↑ Gibb, Gillian C.; Condamine, Fabien L.; Kuch, Melanie; Enk, Jacob; Moraes-Barros, Nadia; Superina, Mariella; Poinar, Hendrik N.; Delsuc, Frédéric (2015). "Shotgun Mitogenomics Provides a Reference PhyloGenetic Framework and Timescale for Living Xenarthrans". *Molecular Biology and Evolution*. **33** (3). PMC 4760074 .
8. ↑ 8.0 8.1 8.2 8.3 8.4 Bartoz, Suzy; Cerda, Anthony (2009). "Silky Anteater". Benedictine University. Archived from the original on October 4, 2013. Retrieved 16 Aug 2009.
9. ↑ Miranda, F.; et al. (2009). "Food habits of wild silky anteaters (*Cyclopes didactylus*) of São Luis do Maranhão, Brazil". *Edentata*. **8–10**: 1–5. doi:10.1896/020.010.0109. hdl:11336/80378 .
10. ↑ Husson, A. M. (1978). *The mammals of Suriname*. Leiden: Brill. p. 569. ISBN 9789004058194.
11. ↑ "Silky Anteater". WildMagazine. Retrieved 1 February 2012.
12. ↑ Sunquist, M.E.; Montgomery, G.G. (1973). "Activity pattern of a translocated silky anteater (*Cyclopes didactylus*)". *Journal of Mammalogy*. **54** (3): 782. doi:10.2307/1378984. JSTOR 1378984.
13. ↑ Nascimento Gomes, Ana Paula; Cesário, Clarice Silva; Olifiers, Natalie; de Cassia Bianchi, Rita; Maldonado, Arnaldo; Vilela, Roberto do Val (December 2019). "New morphological and genetic data of *Gigantorhynchus echinodiscus* (Diesing, 1851) (Acanthocephala: Archiacanthocephala) in the giant anteater *Myrmecophaga tridactyla* Linnaeus, 1758 (Pilosa: Myrmecophagidae)". *International Journal for Parasitology: Parasites and Wildlife*. **10**: 281–288. doi:10.1016/j.ijppaw.2019.09.008 . PMID 31867208.