A new species of Titi Monkey from the Amazon Rainforests of Brazil.

Titi Monkeys, Callicebus spp., are a large group of New World Monkeys distributed throughout much of the Amazonian and Atlantic Rainforests of South America. View on their taxonomy have varied considerably since the discovery of the group in 1903, though it is now accepted that the group is divided into a large number of species with limited distributions. Boundaries between species are generally determined by rivers, as Titi Monkeys do not swim, and are not fond of flooded forests.

In a paper published in the Papéis Avulsos de Zoologia of the Museu de Zoologia da Univeridade de São Paulo on 31 December 2014, Julion César Dalponte of the Instituto para a Conservação dos Carnívoros Neotropicais at Parque Edmundo Zanoni, Filipe Ennes Silva of the Instituto de Desenvolvimento Sustentável Mamirauá and José de Sousa e Silva Junior of the Coordenação de Zoologia at the Museu Paraense Emílio Goeldi describe a new species of Titi Monkey from the Amazon Rainforests of Brazil.

The new species is named Callicebus miltoni, in honour of Milton Thiago de Mello for his numerous contributions to primatology, and in particular his participation in the creation of the Brazilian Primatology Society and of the Latin American Primatology Society, and the foundation of a specialized primatology program at the Universidade de Brasília in the 1980s, which has contributed to most currently active primatologists in Brazil and many overseas.

Family group of Callicebus miltoni in the undercanopy of the ombrophilous forest at Panelas, right bank of the Roosevelt River, northwestern Mato Grosso, Brazil. Adriano Gambarini in Dalponte et al. (2014).

Callicebus miltoni has a distinctive coat, with ab agouti-grey pelt on the back and sides, crown, base of the tail and outer sides of the limbs, lighter grey or white in a band across the forehead, ears and on the hands and feet with the ears also having white rims and a white tuft. The sides of the face, belly, insides of the limbs and most of the tail are dark ochre of orange brown, the eyelids are beige.

The coat of Callicebus miltoni. Stephen Nash in Dalponte et al. (2014).

Callicebus miltoni is distributed between the Roosevelt and Aripuanã rivers to the south of the Amazon as far south as the base of the Dardanelos Plateau, and area known as the Roosevelt-Aripuanã Depression, which covers parts of Mato Grosso, Amazonas and Rondônia. About 25% of this area is covered by conservation units including sustainable use preserves and fully protected areas. A further 32% of this area is covered by land designated for use by indigenous peoples, with the remaining 43% either under private ownership or in areas assigned for settlement. 86% of deforestation currently occurring within this region occurs within one of the protected areas, the Reserva Extrativista Guariba-Roosevelt, though deforestation is clearly a threat in other parts of the area, particularly the mosaic reserves of the Áreas de Proteção Permanente. The potential future damming of the Roosevelt River is also a possible future threat to the Monkeys. The species is not currently hunted, though this could occur in the future, particularly in indigenous use areas, where Amazonian communities traditionally capture infant Monkeys for use as pets, and sometimes trade these with other communities and outsiders.

Geographic distribution of Callicebus miltoni. Dalponte et al. (2014).

Callicebus miltoni was found living in areas of ombrophilous alluvial forest (expand) with four distinct layers of vegetation. The canopy, with an average height of 30 m, comprises Seringueira (Hevea spp.), Jatobá (Hymenaea intermedia), Roxinho (Peltogyne catingue), Garapeira (Apuleia molaris), Copaíba (Copaifera spp.), Jutaí (Dialium guianense), Sucupira-preta (Diplotropis racemosa), Cumaru-champanhe (Dipteryx odorata), Tento (Ormosia nobilis) and Faveira (Parkia sp.) trees with an open distribution. Beneath this an undercanopy layer with an average height of 15 m comprises Matamatámirim (Eschweilera wachenheimii), Aquaricara (Geissospermum urceolatum) and Tachi (Tachigali alba) trees as well as Patauá (Oenocarpus bataua), Sete-pernas (Sochratea exorrhiza) and Açaí (Euterpe precatoria) Palms. Beneath this is a ‘tree’ layer with an open distribution and an average height of 2 m comprising Miconia sp. and Psychotria sp., and lower still a sparse and scattered ‘shrub’ layer reaching 10-50 cm and comprising Olyra cf. latifolia, Selaginella conduplicata and Calthea altissima.

Open ombrophilous alluvial forest at the right bank of the Roosevelt River, habitat of Milton’s Titi Monkey, Callicebus miltoni. Adriano Gambarini in Dalponte et al. (2014).

Callicebus miltoni was observed in the canopy and undercanopy layers of this forest, where it was seen to feed on fruits of Ingá (Inga sp.), Embaúba (Cecropia sp.) and Cacauí (Theobroma speciosum). The Monkeys appeared to be in groups comprising two to five individuals, though more may have been present in the dense canopy and have gone unobserved, as they were extremely cautious of Humans and tended to flee once they realized they were being watched. Like other Titi Monkeys, Callicebus miltoni groups engage in bouts of communal calling, particularly in the mornings and in the rainy season. These calls are thought to help maintain group cohesion and mark out territory; the more intensive calling in the rainy season is thought to be connected to a greater need to defend trees when they are in fruit. Playing back recorded group calls led to the Monkeys investigating, facilitating the location of groups being studied.

Adult male Callicebus miltoni. Jorge Lopes in Dalponte et al. (2014).

See also…

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Burmese Snub-nosed Monkey found in China.
The discovery of the Burmese Snub-nosed Monkey, Rhinopithecus strykeri, was announced in January 2011 in a paper in the American Journal of...

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