Factors influencing terrestriality in primates of the Americas and Madagascar.

Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs, and lorises (strepsirrhines), which are mostly arboreal. Numerous ecological drivers and species-specific factors are suggested to set the conditions for an evolutionary shift from arboreality to terrestriality, and current environmental conditions may provide analogous scenarios to those transitional periods.

Necropsies disclose a low helminth parasite diversity in periurban howler monkeys.

Primate-parasite interactions are often investigated via coprological studies given ethical and conservation restrictions of collecting primate hosts. Yet, these studies are inadequate to recover adult helminths for taxonomic identification and to accurately assess their prevalence, intensity, abundance, and site of infection. Fresh carcasses found in anthropogenic landscapes come as informative and reliable alternatives.

Barcoding a can of worms: testing performance as a DNA barcode of Nematoda.

Accurate taxonomic identifications and species delimitations are a fundamental problem in biology. The complex taxonomy of Nematoda is primarily based on morphology, which is often dubious. DNA barcoding emerged as a handy tool to identify specimens and assess diversity, but its applications in Nematoda are incipient.

Ranging behavior drives parasite richness: A more parsimonious hypothesis.

Parasitism is a ubiquitous interspecific interaction that may play an important role in the evolution of hosts and parasites, molding many aspects of their behavior and ecology. Detecting behavioral changes of hosts infected with parasites is not a straightforward task. Extrapolating from individual-level responses to group-level decision-making is still a much more complex challenge.

A new species of Cacatuocotyle (Monogenea, Dactylogyridae) parasitizing two species of Astyanax (Ostariophysi, Characidae) in southern Brazil.

A new species of Cacatuocotyle is described from the external surface of Astyanax aff. fasciatus and Astyanax jacuhiensis from Lake Guaíba, State of Rio Grande do Sul, Brazil. It differs from the other three species of the genus, recorded from Mexico and the State of Paraná, Brazil, by possessing an accessory piece with a long proximal portion, a U-shaped bar with irregular posterior margin in its midportion, and a haptor containing two circular thickenings with muscular anterior margins.

Urbanization breaks up host-parasite interactions: a case study on parasite community ecology of rufous-bellied thrushes (Turdus rufiventris) along a rural-urban gradient.

Urbanization drastically alters natural ecosystems and the structure of their plant and animal communities. Whereas some species cope successfully with these environmental changes, others may go extinct. In the case of parasite communities, the expansion of urban areas has a critical effect by changing the availability of suitable substrates for the eggs or free-larval stages of those species with direct life cycles or for the range of hosts of those species with complex cycles.

Seasonal influences on parasite community structure of Turdus rufiventris (Aves).

Seasonality has strong effects on natural systems by influencing resource availability, thereby interfering in plant-herbivore, prey-predator, and host-parasite interactions. We compared the seasonal structure of the helminth community of rufous-bellied thrushes (Turdus rufiventris), assessed its correlation with environmental variables, and interpreted temporal patterns of parasite abundance in relation to their life cycles and likely changes in the availability of intermediate hosts and vectors. Fifteen helminth species were found in a sample of 151 thrushes collected on a seasonal basis over 3 yr.