Helminth fauna of the screaming hairy armadillo Chaetophractus vellerosus from Argentina: the consequence of host isolation on parasite diversity

Ovarian Filariasis in a Wild Southern Tamandua (Tamanduatetradactyla; Mammalia: Myrmecophagidae)

Knowledge of reproductive health in wild southern tamanduas (Tamandua tetradactyla; Mammalia: Myrmecophagidae) is fragmentary. During necropsies of roadkill xenarthran species in Brazil, a case of ovarian filariasis in an adult female southern tamandua was observed. Macroscopically, both ovaries were irregularly enlarged and had numerous smooth protuberances. Histologically, the affected ovarian parenchyma presented adult nematodes (including females with microfilaria) surrounded by pleocellular inflammatory infiltrates. The morphological characteristics of the nematodes were consistent with the superfamily Filarioidea (order Spirurida). The adjacent ovarian parenchyma had developing and atretic follicles at different stages of maturation. Filarial nematodes were not observed in other tissues. The cause of death of this tamandua was fatal acute polytrauma as a consequence of the motor vehicle collision. This case adds to a prior report of ovarian filariasis in two southern tamanduas in Nicaragua and Guatemala, dating back almost 100 years, and suggests filarial infections could potentially have an impact on reproductive success in southern tamanduas and possibly other xenarthrans. Several xenarthran species are under different levels of threat and knowledge of their basic reproductive health is crucial for conservation programs.

An annotated checklist of the genus Pterygodermatites Wedl, 1861 (Nematoda: Rictulariidae), with notes on hosts and geographical distribution

Species of rictulariid nematodes belonging to the genus Pterygodermatites Wedl, 1861 are parasites of mammals with a wide geographical distribution. The taxonomy of this speciose genus is complex and based mainly on morphological traits of the cephalic structures and cuticular processes. Currently, the known species are allocated to five subgenera [P. (Paucipectines), P. (Neopaucipectines), P. (Multipectines), P. (Pterygodermatites) and P. (Mesopectines)], based on the classification proposed in 1969 by Quentin. Studies on life cycles, taxonomy, biogeography and association of these parasites with mammals peaked at the end of the 1960s. Although the momentum was lost, new species and geographic records have been added in the last 50 years. Therefore, an updated checklist of species of Pterygodermatites is presented here, based on a literature survey. Information on classification, geographical distribution and host range obtained for 68 species is presented, including a distribution map. Moreover, the main differential morphological traits related to each species are tabulated. More than 140 species from 10 different mammalian orders (Carnivora, Chiroptera, Didelphimorphia, Erinaceomorpha, Macroscelidae, Microbiotheria, Paucituberculata, Primates, Rodentia and Xenarthra) have been reported as hosts of Pterygodermatites spp. The taxonomic information here compiled can contribute to future studies on the biogeography, in addition to evolutionary and ecological aspects of this diverse but poorly known genus of parasitic nematodes of mammals.

Helminth-fauna of Patagonian armadillos: comparative analysis of parasites geographical variation

The similarity between parasites communities' decay with distance and its analysis may explain important ecological process such host dispersion. Patagonia is inhabited by two armadillo species, Chaetophractus villosus and Zaedyus pichiy. In this study we describe and analyze the variation on helminth fauna of these armadillos in Patagonia compared with northern localities described in previous studies. A total of 49 armadillos were collected in Patagonia. Quantitative descriptors of parasite ecology were calculated and community structure of helminths was analyzed following the central-satellite species hypothesis. The parasite richness in Patagonia decreases almost 50% in both armadillos. Zaedyus pichiy present the same central species in Patagonia as in northern localities. For C. villosus central-satellite species analysis could not be applied. The loss of some helminths in Z. pichiy could be the result of lower temperatures or the absence of intermediate arthropods hosts. But in C. villosus the absence of some helminths with Patagonian distribution could be explained by its recent dispersion in Patagonia. Trichohelix tuberculata still being the only helminth in C. villosus introduced population of Tierra del Fuego.