Mico melanurus


Taxonomy [top]

Kingdom Phylum Class Order Family

Scientific Name: Mico melanurus
Species Authority: (É. Geoffroy in Humboldt, 1812)
Common Name(s):
English Black-tailed Marmoset
Taxonomic Notes: Formerly in the genus Callithrix (see Rylands et al. 1993, 2000, 2008). Groves (2001, 2005) lists this species as Callithrix (Mico) melanura.

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2008
Date Assessed: 2008-06-30
Assessor(s): Rylands, A.B., Mittermeier, R.A. & Wallace, R.B.
Reviewer(s): Mittermeier, R.A., Rylands, A.B. (Primate Red List Authority) & Hoffmann, M. (Global Mammal Assessment Team)
Listed as Least Concern as this species is wide-ranging and adaptable, and there are no major threats resulting in a significant population decline.

Geographic Range [top]

Range Description: The most widespread of the "argentata" group marmosets, M. melanurus is the only one to occur naturally outside of Brazil, extending south through the Pantanal of Mato Grosso into Bolivia and Paraguay. Hershkovitz (1977) indicated the Rio Tacuarí in Brazil and the headwaters of the Río Mamoré in Bolivia as the southern limit of its distribution, but Stallings and Mittermeier (1983) and Stallings (1985) recorded it also from the north-eastern Paraguayan chaco, extending the known range to approximately 20ºS. In Bolivia, it occurs east of the Río Mamoré, in the Departments of Beni and Santa Cruz (Brown and Rumiz 1986; Anderson 1997).

According to Hershkovitz (1977), in Brazil it occurs to the east of the Rio Madeira, from the mouth of the Rio Aripuanã extending south to beyond the Rio Guaporé and west to the Rio Roosevelt. However, field research and the discovery of a number of distinct new marmosets has modified the range he proposed. In the state of Rondônia evidence has not been forthcoming for its occurrence between the Rios Aripuanã and Roosevelt (the range of M. intermedius). It does occur on the east bank of the Rio Aripuaná, north at least to 10ºS, and probably west to the Rio Juruena, or the Rio Teles Pires, where Ávila-Pires (1986) predicted that it would meet the range of the form M. emiliae. Hershkovitz’s (1977) proposal for its occurrence west of the Rio Aripuanã-Roosevelt was based on three localities. The first was the Foz do Rio Castanho (near the junction of the Rios Roosevelt, Guariba, and Aripuanã in the state of Amazonas) (locality 197b, p.569, Hershkovitz 1977). This is the type locality of the distinct form M. marcai described by Alperin (1993). According to Vivo (1985), the marmosets at the other two localities indicated by Hershkovitz (1977: 214b, mouth of the Rio Jiparaná, upper Rio Madeira; and 214c, Urupá, Rio Jiparaná) would not be the form melanura, but Callithrix emiliae according to their similarity (although darker) to the marmosets from the Rio Curuá, in Pará (the type locality of M. emiliae [Thomas, 1920]). However, the “Callithrix emiliae” of Vivo (1985) occurs to the west of the range of M. melanurus and, if aligned with the Callithrix emiliae of Thomas (1920), listed by Cruz Lima (1945), Cabrera (1957) and Ávila-Pires (1986), would indicate a disjunct distribution, being separated by typical M. melanurus between the Rios Aripuanã and Juruena (or Teles Pires). The Rondônia marmoset of Vivo (1985, 1991) is distinct from melanurus in its paler colour (less brownish dorsum) and the lack of the distinct pale thigh stripe.
Bolivia, Plurinational States of; Brazil (Amazonas, Mato Grosso, Rondônia); Paraguay
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: In the north-eastern Paragyana Chaco, Stallings (1985) recorded densities of 1.6 groups/km² (Agua Dulce) and 3.52 groups/km² (Chovoreca) , with mean group sizes of 4.6 and 7.8 individuals, respectively.
Population Trend: Unknown

Habitat and Ecology [top]

Habitat and Ecology: Mico melanurus is known from the Amazon lowland rain forest of the state of Mato Grosso, extending south form the south and east of Serra dos Pacáas Novos into Bolivia and Paraguay. Stallings and Mittermeier (1983) and Stallings (1985) found M. melanurus in the northeastern Chaco. The habitats there are diverse and annual precipitation is high. There it occurs in tall forest along the ephemeral waterways or cauces (Stallings 1985). Recorded during surveys in the mountainous region of Huanchaca, eastern Bolivia, by Braza and García (1987). In Bolivia, it occurs in primary and secondary growth forest, dry, deciduous forests, gallery forest and forest patches in savannas (Tarifa,1996).

Marmosets and tamarins are distinguished from the other monkeys of the New World by their small size, modified claws rather than nails on all digits except the big toe, the presence of two as opposed to three molar teeth in either side of each jaw, and by the occurrence of twin births. They eat fruits, flowers, nectar, plant exudates (gums, saps, latex) and animal prey (including frogs, snails, lizards, spiders and insects). Marmosets have morphological and behavioural adaptations for gouging trees trunks, branches and vines of certain species to stimulate the flow of gum, which they eat, and in some species form a notable component of the diet (Coimbra-Filho and Mittermeier 1976; Rylands 1984). They live in extended family groups of between four and 15 individuals. Two groups seen by Braza and García (1987) were of 7 and 12 individuals. Stallings (1985) recorded mean group sizes of 4.6 (Agua Dulce) and 7.8 individuals (Chovoreca) in Paraguay. Generally only one female per group breeds during a particular breeding season. The groups defend home ranges 10-40 ha, the size depending on availability and distribution of foods and second-growth patches.

Mean H&B 22.6, T 33.0 (N=30) (Ferrari 2008).
Systems: Terrestrial

Threats [top]

Major Threat(s): A wide ranging species with no obvious major threats at present. Generally not hunted, though there is some use as pets.

Conservation Actions [top]

Conservation Actions: Protected by Decreto de Veda General Indefinida (D.S. 22641, 1990) in Bolivia (Tarifa 1996).

This species occurs, or may occur, in several protected areas, including:

Amboró National Park (?) (98,640 ha) (637,600 ha - WCMC DB)
Noel Kempff Mercado National Park (927,000 ha) (WCMC DB)
Noel Kempff Mercado National Reserve (21,900 ha) (WCMC DB)

Pantanal Matogrossense National Park (135,000 ha)
Chapada dos Guimarães National Park (33,000 ha)
Taiamá Ecological Station (14,325 ha)
Serra das Araras Ecological Station (28,700 ha)
Iquê Ecological Station (?) (200,000 ha)

Defensores del Chaco National Park (780,000 ha) (Stallings 1985, 1989)

It is listed on Appendix II of CITES (as Callithrix melanura).

Citation: Rylands, A.B., Mittermeier, R.A. & Wallace, R.B. 2008. Mico melanurus. The IUCN Red List of Threatened Species. Version 2014.3. <>. Downloaded on 19 December 2014.
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