Mico intermedius
Creators: name: Russell A. Mittermeier
name: Anthony B. Rylands
name: Don E. Wilson
Publisher: name: Lynx Edicions
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Primates
Callitrichidae
Mico
Mico intermedius

description: 7.
Rio Aripuana Marmoset
Mico intermedius
French: Ouistiti de I'Aripuana / German: Rio-Aripuana-Seidenaffchen / Spanish: Titi de Aripuané Other common names: Aripuana Marmoset, Hershkovitz's Marmoset
Taxonomy. Callithrix humeralifer intermedius Hershkovitz, 1977,
Brazil, near mouth of Rio Guariba, left bank of Rio Aripuana, south-eastern Amazonas.
This species is monotypic.
Distribution. Brazilian Amazon between rios Roosevelt and Aripuana, the S limits are not known, but probably around the headwaters of the Aripuana and Roosevelt.
Descriptive notes. Head-body 20-24 cm, tail 32-40 cm; weight ¢.280 g (males) and c.310 g (females). The forequarters of the Rio Aripuana Marmoset are whitishsilvery, whitish, or yellowish-white, and fur becomes irregularly spotted with chestnut on the posterior one-half of the forequarters. Upper part of the chest is creamy-white, underparts are pale orange, the thigh stripe is golden-yellow, and the rump (including the base of the tail) is dark brown. The tail is pale off-white and not ringed. Face and ears are pink or variably pigmented with gray, and the crown is grayish. There are rudimentary white ear tufts, originating from the external surfaces only.
Habitat. Dense primary and secondary rainforest, with distinct wet (December—March) and dry (May—October) seasons. A field study of the Rio Aripuana Marmoset carried out at Aripuana, on the left bank of the Rio Aripuana in 1978 and 1979, found that they were more common in disturbed forests patches, with denser understories and vine tangles, resulting from tree falls or human disturbances. They are scarce in riparian flooded forest and tall forest with minimal and sparse undergrowth. One group was observed in white-sand forest (smaller-leaved, with a floristic community quite distinct from the surrounding clay-soil forest).
Food and Feeding. The Rio Aripuana Marmoset eats mostly small and sweet fruits, nectar, gums, and small animal prey. Fruits contributed 32-94% of the plant part of the diet each month, exudates 6-59%, and flowers and nectar 4:5-18%, just from April to September (end of the dry season). During a twelve-month period, a group of Rio Aripuana Marmosets fed on fruits of 52 plants in 24 families. Among the most important families providing fruits were Moraceae (contributing 14 species, including Pseudolmedia, Naucleopsis, Sorocea, Ficus), Urticaceae (Cecropia, Pourouma), Burseraceae (Protium, Tetragastris), and Fabaceae (Inga). Species of three genera, Pourouma, Inga, and Cecropia, had long, piecemeal, fruiting seasons and provided fruits for the entire year and, in many months, were predominant in the diets. Cecropia was particularly important during the dry season when fruits were otherwise scarce compared with the early and middle wet season. Flowers and nectar of Symphonia globulifera were important in the dry season from July to September. Rio Aripuana Marmosets gouged tree trunks, branches, and lianas (“cipos”) throughout the year, but exudates were predominant in the diet in the last months of the wet season (March-April) when fruits were exceptionally scarce. Exudate sources included 34 species in twelve families. Fourteen were legumes (e.g. Enterolobium, Hymenolobium, Parkia, Diplotropis, Inga, and Acacia), and species of Anacardiaceae (cashew family: Anacardium, Spondias, Tapirira) and Meliaceae (Trichilia guianensis) also were important sources of exudate. Depending on the month, 25-34% of their daily activity was spent searching for and feeding on small animal prey. Rio Aripuana Marmosets eat insects, spiders, small lizards, and frogs. Insect prey include Orthoptera, notably Tettigoniidae (long-horned grasshoppers), Acrididae (short-horned grasshoppers), Gryllidae (crickets), Mantodea (praying mantises), Isoptera (termites), Lepidoptera (butterflies and moths), Coleoptera (beetles), Hemiptera (cicadas and others), Blattaria (cockroaches), and Phasmida (stick insects). When searching for prey they move slowly through dense vegetation, searching clumps of dead leaves, humus clumps at the bases of epiphytes, and under leaves along branches (particularly for grasshoppers resting during the day). Occasionally, Rio Aripuana Marmosets go to the ground and search stealthily in the leaf litter. They also forage above swarms of army ants (Eciton burchellii cupiens), staying at the head of the swarm, picking offfleeing and disturbed insects.
Breeding. Despite the supernumerary adults in each group, breeding is generally restricted to a single female at any one time. In the single study of a group of Rio Aripuana Marmosets, a female gave birth to three sets of twins in a year: early September (early wet season), early February (mid- to late wet season), and mid-July (dry season). Infants in three other groups were seen in August-September and January-February. Interbirth intervals for the female that produced twins three times were 148-162 days and 154-160 days, which is only a little longer than the gestation period of ¢.150 days. Births twice a year would seem to be the norm. One adult male carried infants on the day of their birth. Other adult group members carried infants as soon as two days after their birth. Two males, however, were particularly active in carrying the twins, and three males were seen copulating with the breeding female, indicating the possibility of polyandry rather than a monogamous breeding system. After about three weeks, infants were carried separately and began to spend time off of their adult carriers. Parking of infants was seen occasionally.
Activity patterns. Rio Aripuana Marmosets begin their day ¢.30 minutes to one hour after sunrise and return to their sleeping sites at ¢.16:00 h, sometimes later and sometimes earlier, especially when it is raining. Sleeping sites include dense liana tangles, low bushy vegetation, low trees with dense crowns, and occasionally tree holes. Heights of sleeping sites varied from c.50 cm above the ground to 20 m up in the canopy. On average, individuals spent 38% of their day traveling, 30% foraging for animal prey, 18% foraging on plant foods (fruits, exudates, or flowers), and 14% resting and engaged in social activities, such as grooming.
Movements, Home range and Social organization. Home range size of one group of Rio Aripuana Marmosets that was studied over a full year was 28-2 ha, with monthly sizes from 11-5 ha to 21-5 ha. Less than one-half of the home range (44%) was used 90% of the time. Daily movements were 772-2115 m, with overall monthly means of 1200-1774 m; the group visited between one-third and a little less than one-half of its home range each day. Group size was 8-15 individuals, with a mean of 11-5 individuals among eight groups. Groups include 1-4 adult males, 1-5 adult females, and varying numbers of subadults, juveniles, and infants. Encounters between groups at the borders of their home ranges are characterized by calling, displaying, chasing, and scent marking. Displays, sometimes involving the majority of individuals in each group facing each other a few meters apart, include frowning (lowering the head and eyebrows and staring), rapid scratching of the tail (held in one hand and scratched with the other), and tail-raising (presenting their genitalia with the tail raised and looking back toward the opponents). Agitation with much long calling is typical of these encounters, which can last up to 2-3 hours, with intervals of 5-15 minutes when respective group members come together and rest and groom. Densities of the Rio Aripuana Marmoset in tall forest with sparse undergrowth were 0-44-0-57 groups/km?, whereas in areas with patches of disturbed successional forest with denser vegetation in the understory, they were more abundant (3-1-4-7 groups/km?).
Status and Conservation. CITES Appendix II. Classified as Least Concern on The IUCN Red List. The Cuiaba-Porto Velho Highway bisects the distribution of the Rio Aripuana Marmoset, east to west, and is resulting in a steady destruction of the forests between the rios Aripuana and Roosevelt where it lives. Urbanization, logging, and cattle ranching are destroying and fragmenting forests of the entire northern Mato Grosso State. The Rio Aripuana Marmoset does not occur in any protected area.
Bibliography. Hershkovitz (1977), Rylands (1981, 1982, 1984, 1986a, 1986b, 1989b, 1990), Rylands & de Faria (1993), Rylands et al. (1993, 2009), Stevenson & Rylands (1988).
description: Published as part of Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Callitrichiade, pp. 262-346 in Handbook of the Mammals of the World – Volume 3 Primates, Barcelona :Lynx Edicions on pages 310-311, DOI: 10.5281/zenodo.5730714