Trichurid nematodes from South American Camelid: an approach to native assemblages through the parasitology of archaeological sites.

To gain insights into the trichurid diversity in pre-Hispanic remains of South American camelids (SACs), as well as into modern SAC populations, a bibliographic search was carried out to find parasitological studies. Results showed that a total of 17 studies were performed at archaeological and paleontological sites, in which a total of 213 samples were examined. The sample set was used as the unit of analysis, and 83% of 52 pre-Hispanic sample sets were positive for parasites. Parasitological studies confirmed the pre-Hispanic presence of diverse trichurids: two Trichuris species and capillariid eggs with morphological differences that allowed them to be assigned to three different species. Currently, the richness of the native trichurid assemblages in SACs has been extended by the inclusion of two species (Trichuris sp. 2 and Capillariinae gen. sp. 1). Modern T. tenuis Chandler, 1930, considered SAC-specific, would have invaded SAC populations during the European colonization. The estimate of regional and temporal trichurid prevalence and paleoecological information allowed us to propose a possible origin for some of them. Although the present analysis is exploratory, it should stimulate future studies about the biogeographic history of SAC helminths, provide relevant information to improve descriptions of the Holocene ecology, and identify threatened helminths.

Updated checklist of helminths found in terrestrial mammals of Argentine Patagonia.

The aim of the present study was to evaluate the state of knowledge about the helminthology of wild mammals in Argentine Patagonia and its link with the conservation of parasite species and biodiversity. To this end, the information included in the previously reported checklist of the helminths found in terrestrial wild mammals of Argentine Patagonia was completed and updated. The methodology used for the search was the same as that previously used, with slight modifications. Eighty-two species of mammals currently inhabit the region, and an additional six species are considered to have become extinct before the 20th century. The reports used to complete and update the information correspond to research done since 2015 to date. Considering the number of records analysed in the previously reported checklist and those of the current update, a total of 1918 helminthological reports for current Patagonian mammals and 2141 on mammal species that inhabited Patagonia before the 20th century were accounted for. It is important to point out that 41% of the 82 species of wild mammals currently inhabiting Patagonia have not been studied helminthologically; 38% of these without helminthological records are either threatened or do not have categorization, and 79% of mammals without helminthological studies have some degree of endemism. Therefore, in order to evaluate conservation priorities, the information about the parasitic richness in Patagonian wild mammals should be substantially increased, especially in those endangered or endemic.

Fox parasites in pre-Columbian times: Evidence from the past to understand the current helminth assemblages.

This work aims to increase the information on the entero-parasitism in Holocene carnivores, by examining coprolites found in Patagonia. Molecular analysis was conducted following the Authenticity Criteria to Determine Ancient DNA sequences. The nucleotide sequences showed 99% of identity with the Control Region sequences of Lycalopex culpaeus (culpeo fox). Coprolites were positive for gastrointestinal parasites. The presence of Alaria sp. and Clonorchis sp. represents the first record for pre-Columbian America. The parasitological findings suggest the importance of these carnivores for the dissemination of their own parasites and those to their prey in rockshelters, areas with high re-use of space.

Apex Predators, Rockshelters, and Zoonoses in the Patagonian Holocene.

Carnivorous mammals are a trophic guild with an important role in the dissemination of parasite infective stages (larvae, eggs, cysts, and oocysts). In the present study, new samples of coprolites attributed to carnivorous mammals, obtained from 2 archaeological caves, were analyzed for the presence of parasites with the aim to increase the knowledge about parasites in rockshelters that could have spread to humans and other mammals. To this purpose, fragments of 3 coprolites from Cerro Casa de Piedra, cave 5 and cave 7, were examined. Coprolites were rehydrated in aqueous trisodium phosphate and processed by spontaneous sedimentation. High parasite richness was observed and new parasite species for archaeological contexts were found. The parasitological findings in Puma concolor coprolites associated with caves suggest the importance of these carnivores in the dissemination of parasites in areas with high re-use of space and steady conditions of temperature, humidity, and radiation.

New parasitological findings for pre-Hispanic camelids.

Paleoparasitological examination provides information of parasite-host associations in the past, shedding light on the geographical origin of some parasites, on the possible dispersal routes and on some of the processes that modelled the parasitic communities. The aim of the present study was to examine parasite remains present in camelid coprolites collected from the archaeological site Alero Destacamento Guardaparque, Patagonia and to discuss the paleoparasitological findings in a biogeographical and paleoecological context. Coprolites were collected from different stratified layers dating from middle to late Holocene, a period covering approximately 7000 years. Paleoparasitological examination revealed the presence of eggs attributed to Lamanema chavezi or Nematodirus lamae, Nematodirus spathiger, Dictyocaulus sp., eggs of two unidentified capillariids, Strongylus-type eggs and oocysts of Eimeria macusaniensis. Enteric parasites of camelids had not changed significantly during the Holocene up to the entry of introduced livestock, although environmental conditions fluctuated greatly throughout this period, indicating the stability of these associations over time. This is the first finding of N. spathiger and Dictyocaulus sp. in paleoparasitological record and their presence are associated with the interaction of camelids with introduced livestock, which likely allowed parasite host switching. In the present study, the zoonotic importance of parasites of camelids is also discussed.

Biometric identification of capillariid eggs from archaeological sites in Patagonia.

Numerous eggs of capillariid nematodes have been found in coprolites from a wide range of hosts and in raptor pellets in archaeological samples from Patagonia. The structure and sculpture of the eggshell of these nematodes and their biometry are commonly used for identification. The aim of this study was to determine whether eggs of the genus Calodium with similar morphology, found in different archaeological samples from Patagonia, belong to the same species. For this purpose, capillariid eggs (N= 843) with thick walls and radial striations were studied by permutational multivariate analysis of variance (PERMANOVA). Eggs exhibiting similar shape and structure also showed similar biometry, regardless of the zoological origin of coprolites (P= 0.84), host diet (P= 0.19), character of the archaeological sites (P= 0.67) and chronology (P= 0.66). Thus, they were attributed to the same species. We suggest that an unidentified zoonotic species of the genus Calodium occurred in the digestive tract of a wide range of hosts in Patagonia during the Holocene and that both human and animal populations were exposed to this parasite during the Holocene in the study area.

DNA extraction and a cost-effective detection method for Echinococcus granulosus protoscoleces.

Most methods of DNA purification from protoscoleces of Echinococcus granulosus involve the use of expensive kits and may also require a second step after extraction for an effective purification. The present work describes an optimized cost-effective method that is fast and simple. This method is based on a chemical lysis with proteinase K with a subsequent one-step PCR detection. In this study we used already available primers and newly designed primers to amplify two fragments of different size corresponding to the mitochondrial cytochrome C oxidase subunit 1 gene. By one-step PCR, both fragments were successfully amplified from even a single protoscolex. This result demonstrates that this method of extraction is efficient even with small amounts of sample and that PCR is highly sensitive. The major advantage of this lysis-PCR method is that it avoids a second step of purification resulting in a simpler and more economical method. Our research will serve as a base for future studies on E. granulosus genotyping, mainly with wild mammals with a low number of cysts.

Paleoparasitological finding of eggs of nematodes in rodent coprolites dated at the early Holocene from the archaeological site Cerro Casa de Piedra 7, Santa Cruz, Argentina.

The aim of the present study was to examine the parasite remains present in rodent coprolites collected from the archaeological site Cerro Casa de Piedra 7 (CCP7), located in the Perito Moreno National Park (47°57'S, 72°05'W), Santa Cruz Province, Argentina. Eight coprolites obtained from the layer 17, dated at 10,620 ± 40 to 9,390 ± 40 yr B.P., were examined for parasites. Feces were processed whole, rehydrated, homogenized, subjected to spontaneous sedimentation, and examined via light microscopy. Eggs of parasites were measured and photographed. Seven of 8 coprolites possessed 199 eggs of 2, probably new, species of nematodes, including 43 eggs of Heteroxynema sp. Hall, 1916 (Cavioxyura sp. Quentin, 1975) (Oxyurida, Heteroxynematidae), and 156 eggs of Trichuris sp. Roederer, 1761 (Trichinellida, Trichuridae). Heteroxynema sp. is cited for the first time from ancient material worldwide. The finding of Trichuris spp. in both rodents and other host samples from the area under study is indicative of the stability of the biological and environmental conditions for this nematode genus to establish in the Patagonian Early Holocene. The rodent host was assigned to an unknown species of Caviomorpha (Hystricognathi) that lived during the Pleistocenic transition in Patagonia.

First paleoparasitological results from late Holocene in Patagonian coprolites.

These are the first paleoparasitological results from the Late Holocene in Patagonian coprolites. Coprolites collected from layers dated at 3,480 and 2,740 yr before present (B.P.), from the archaeological site Cerro Casa de Piedra, were examined. The site is a hill located in a forest steppe ecotone in Perito Moreno National Park. The coprolites could belong to humans or to other carnivores such as canids. After rehydration and spontaneous sedimentation of the samples, the parasite contents were examined. Results obtained showed the common presence of eggs of a Calodium sp., eggs of other capillariids and trichostrongylids, oocysts of Eimeria macusaniensis (Apicomplexa), and eggs of taeniids (Cestoda). Although the generic identification of some parasites could not be provided, the presence of tapeworm eggs represents the first record for the Late Holocene in Patagonia and shows that parasitism by cestodes existed in the region in pre-Columbian times. Results indicate that in the Late Patagonic Holocene, zoonotic helminths may have been commonly present in the inhabitants of Patagonia. The parasites found in the coprolites allow us to deduce what these people were eating and, thus, indicate what other pathogens, such as viruses, bacteria, and parasitic protozoans, may have infected them via the same sources.

Eimeriid oocysts from archaeological samples in Patagonia, Argentina.

Oocysts attributable to E. macusaniensis Guerrero et al. 1971, were found in coprolites and in archaeological sediments dating to the Holocene of Patagonia, Argentina. By means of a non-parametric regression using a generalized additive model, a significant relationship was found between the size of the oocysts and their antiquity. Specifically, a reduction in oocyst size over time was discovered, probably due to a parasite response to host replacement, to an extinct eimeriid species common during the Pliestocene-Holocene transition, or to environmental changes known for the Holocene. Explanations regarding coevolution between parasites, hosts and paleoenvironmental conditions are discussed herein.

Paleoparasitological analysis of a raptor pellet from southern Patagonia.

Organic remains attributable to one regurgitated pellet were examined. The pellet, belonging to a bird of prey and collected from a cave of Southern Patagonia, was dated at 6,540 +/- 110 yr. With standard paleoparasitological procedures, eggs of Capillaria sp. and a mite, Demodex sp., were found. The parasites found in the pellet belong to a rodent ingested by the bird. The present report constitutes the first paleoparasitological study of a regurgitated pellet.

Paleoparasitological records in a canid coprolite from Patagonia, Argentina.

In this note, organic remains identified as a canid coprolite were examined. The material was dated at 6540 +/- 110 B.P.; it was collected in the Perito Moreno National Park, Santa Cruz, Argentina. Paleoparasitological analysis was performed following standard procedures. Coprolite fragments were rehydrated in a trisodium phosphate aqueous solution and subjected to spontaneous sedimentation for microscope analysis. Eggs of nematodes identified as Trichuris sp., Capillaria sp., Uncinaria sp., and an ascaridid (probably Toxascaris sp.) or spirurids (presumably Physaloptera sp.), plus a cestode (Anoplocephalidae), presumably Moniezia sp., were found.