Silvered leaf monkey

Abstract: Within phylogenetic limits reproductive characteristics of a given species may vary between populations in response to ecological and social factors. For instance, in environments where high quality nutrition is readily available, the onset and speed of reproduction are often accelerated. Other influencing factors might be maternal experience or the sex of the infant. Here we present data on reproductive characteristics for the silvered leaf monkey (Trachypithecus cristatus), a medium-sized Asian colobine housed at the Wildlife Conservation Society's Bronx Zoo as a one-male group. To place the species into an appropriate phylogenetic context, we limited our comparison to other colobine species. Demographic data span 21.4 years (October 1985 to March 2007) and derive from 30 adult females (128.0 female years). Detailed behavioral data stem from a 2.2 years study (November 2002 to January 2005; 734 days, 4,225 hr). As in other Asian colobines, receptive periods were short (mean=4.3 days, n=68). This is expected for one-male groups where receptivity likely indicates, rather than conceals, ovulation. Gestation length was estimated based on a change in the pattern of sexual behavior (mean=194.6 days, n=7). It fell within the range reported for the taxon. Births occurred year round, at an early age (mean=2.9 years, n=8), at short intervals (mean=14.9 months, n=59) in combination with a short lactation (mean 12.1 months, n=9) likely due to the nearly unlimited availability of nutrition in this zoo setting. Primiparous females tended to have a longer first interbirth interval but infant survival rates were similar to multipara possibly due to the absence of predators. Maternal investment was independent of the infant's sex and birth sex ratio was even. Our results emphasize that when interpreted with caution, zoo populations yield realistic reproductive characteristics that can help fill the gap in our knowledge about colobine life history. Am. J. Primatol. 71:852–859, 2009. © 2009 Wiley-Liss, Inc.

Abstract: On the basis of morphological characteristics of adult and microfilarial stages, Wuchereria kalimantani sp. n. (Nematoda: Filarioidea) is described. The parasites were recovered from the inguinal lymph nodes and testes of silvered leaf monkeys (Presbytis cristatus) from a rubber estate, Banjar Regency, South Kalimantan (Borneo), Indonesia. Adult males are characterized by having more than 24 caudal papillae, a left spicule with a simple lamina, four pairs of sessile caudal papillae, a blunt tail, a mean overall length of 41 mm, and sheathed microfilariae with a nude tail tip; accordingly, the parasite is placed in the genus Wuchereria. This is the second species of Wuchereria described on the basis of both adult and embryonic forms, and is the first such species that has been found to infect primates naturally.

Abstract: On the basis of morphological characteristics of adult and microfilarial stages, Wuchereria kalimantani sp. n. (Nematoda: Filarioidea) is described. The parasites were recovered from the inguinal lymph nodes and testes of silvered leaf monkeys (Presbytis cristatus) from a rubber estate, Banjar Regency, South Kalimantan (Borneo), Indonesia. Adult males are characterized by having more than 24 caudal papillae, a left spicule with a simple lamina, four pairs of sessile caudal papillae, a blunt tail, a mean overall length of 41 mm, and sheathed microfilariae with a nude tail tip; accordingly, the parasite is placed in the genus Wuchereria. This is the second species of Wuchereria described on the basis of both adult and embryonic forms, and is the first such species that has been found to infect primates naturally. The history of Wuchereria began in 1876