Daubaylia potomaca is a nematode parasite that exhibits an unusual direct life cycle in planorbid snails in which adult females are the infective stage, after being shed from a definitive host. The present study examined the shedding patterns of this nematode to determine what cues or mechanisms might lead to the parasite leaving its host. A correlation was found between host death and the frequency and number of D. potomaca shed, suggesting that the nematodes can detect that the host is dying and may leave in search of a new host. Furthermore, elevated intensities of D. potomaca in the snail induce shedding earlier, suggesting that competition for space and resources may also play a role in the shedding patterns of the nematode, but not when time to death is controlled. Finally, nematodes shed a longer time before host death were significantly longer and more likely to be gravid than those shed as time to snail death approached, implying that the nematode reaching maturity or being inseminated might also be cues for D. potomaca to leave its snail host. In summary, the shedding patterns of D. potomaca appear to be a complex mix of host death detection, competition, and nematode maturation.

A new tick species belonging to the African subgenus Afrixodes Morel, 1966 of the genus Ixodes Latreille, 1795, namely, Ixodes (Afrixodes) microgalei n. sp., is described. Females of this species are most similar to those of Ixodes colasbelcouri Arthur, 1957 and Ixodes nesomys Uilenberg & Hoogstraal, 1969. The female of the new species can easily be differentiated from I. colasbelcouri by a short spur on coxae IV, and from I. nesomys by longer spurs on coxae I and large punctations on its scutum. Ixodes microgalei is known only from the eastern humid forest of Madagascar, specifically in the Province of Antananarivo, where its females have been collected from several species of shrew tenrecs (Afrosoricida, Tenrecidae), namely, Microgale dobsoni Thomas, Microgale parvula Grandidier, and Microgale soricoides Jenkins.

We provide new data for the ticks Amblyomma multipunctum and Amblyomma naponense from Ecuador. In addition, we describe the nymph of A. multipunctum for the first time. During December 2012, ticks were collected by dragging in forest trails of 1 locality at Puyo, Pastaza Province (elevation 979 m), and another locality at Papallacta, Napo Province (3,474 m). A total of 10 adults of A. naponense were collected at Puyo, whereas 27 adults and 3 nymphs of A. multipunctum were collected at Papallacta. Compared to sequences of a fragment of the mitochondrial 16S rDNA gene of adult and nymphal ticks, the sequence of an Amblyomma nymph was identical to the sequences generated from the A. multipunctum adults. The 3 collected nymphs (including the 1 used for molecular analysis) had the same morphotype, and were used for the first morphological description of the nymphal stage of A. multipunctum. Sequences generated from the A. naponense specimens were closest (97% identity by BLAST) to a corresponding sequence of A. naponense from Brazil, whereas the A. multipunctum sequences were closer to (90–91% identity) several Neotropical Amblyomma species. Herein, we provide just the second record of A. naponense in Ecuador, more than 100 yr after this tick was reported in this country. Adults and nymphs of A. multipunctum were found in highland, humid montane forest areas, in agreement with the only 2 previous reports of A. multipunctum in Ecuador and Colombia. No genetic differences were found among A. multipunctum ticks that presented significant morphological differences, suggesting intraspecific polymorphism in the adult stages of this species.

Genetic analyses of hosts and their parasites are key to understand the evolutionary patterns and processes that have shaped host–parasite associations. We evaluated the genetic structure of the digenean Crassicutis cichlasomae and its most common host, the Mayan cichlid “Cichlasoma” urophthalmus, encompassing most of their geographical range in Middle-America (river basins in southeastern Mexico, Belize, and Guatemala together with the Yucatan Peninsula). Genetic diversity and structure analyses were done based on 167 cytochrome c oxidase subunit 1 sequences (330 bp) for C. cichlasomae from 21 populations and 161 cytochrome b sequences (599 bp) for “C.” urophthalmus from 26 populations. Analyses performed included phylogenetic tree estimation under Bayesian inference and maximum likelihood analysis, genetic diversity, distance and structure estimates, haplotype networks, and demographic evaluations. Crassicutis cichlasomae showed high genetic diversity values and genetic structuring, corresponding with 4 groups clearly differentiated and highly divergent. Conversely, “C.” urophthalmus showed low levels of genetic diversity and genetic differentiation, defined as 2 groups with low divergence and with no correspondence with geographical distribution. Our results show that species of cichlids parasitized by C. cichlasomae other than “C.” urophthalmus, along with multiple colonization events and subsequent isolation in different basins, are likely factors that shaped the genetic structure of the parasite. Meanwhile, historical long-distance dispersal and drought periods during the Holocene, with significant population size reductions and fragmentations, are factors that could have shaped the genetic structure of the Mayan cichlid.

Notoedric mange was responsible for a population decline of bobcats (Lynx rufus) in 2 Southern California counties from 2002–2006 and is now reported to affect bobcats in Northern and Southern California. With this study we document clinical laboratory and necropsy findings for bobcats with mange. Bobcats in this study included free-ranging bobcats with mange (n = 34), a control group of free-ranging bobcats without mange (n = 11), and a captive control group of bobcats without mange (n = 19). We used 2 control groups to evaluate potential anomalies due to capture stress or diet. Free-ranging healthy and mange-infected bobcats were trapped or salvaged. Animals were tested by serum biochemistry, complete blood count, urine protein and creatinine, body weight, necropsy, and assessment for anticoagulant rodenticide residues in liver tissue. Bobcats with severe mange were emaciated, dehydrated, and anemic with low serum creatinine, hyperphosphatemia, hypoglycemia, hypernatremia, and hyperchloremia, and sometimes septicemic when compared to control groups. Liver enzymes and leukocyte counts were elevated in free-ranging, recently captured bobcats whether or not they were infested with mange, suggesting capture stress. Bobcats with mange had lower levels of serum cholesterol, albumin, globulin, and total protein due to protein loss likely secondary to severe dermatopathy. Renal insufficiency was unlikely in most cases, as urine protein:creatinine ratios were within normal limits. A primary gastrointestinal loss of protein or blood was possible in a few cases, as evidenced by elevated blood urea nitrogen, anemia, intestinal parasitism, colitis, gastric hemorrhage, and melena. The prevalence of exposure to anticoagulant rodenticides was 100% (n = 15) in bobcats with mange. These findings paint a picture of debilitating, multisystemic disease with infectious and toxic contributing factors that can progress to death in individuals and potential decline in populations.

Cats serve as definitive hosts for zoonotic Toxoplasma gondii, a protozoan that threatens human reproductive health, but they also excrete sporocysts of related protozoan that pose no known human health risk. Here we provide the first definitive evidence for natural infection with the enzootic parasite Sarcocystis muris, one such enzootic parasite. Sporulated Sarcocystis sp. sporocysts were found in rectal contents of an adult feral cat (Felis catus) in Giza, Egypt. After these sporocysts were orally inoculated into 2 Swiss Webster mice, sarcocysts were found to have developed in skeletal muscles 114 days later. As observed through transmission electron microscopy, the cyst wall corresponded to Type 1, and the parasitophorous vacuolar membrane had tiny outpocketing of blebs (<200 nm thick) that were not invaginated into the interior of the cyst; these structures were identical to the sarcocyst wall described for a Costa Rican isolate of S. muris that has served as an experimental model for nearly 4 decades. Two parasite-free cats fed sarcocyst-infected muscles developed patent infections; fully sporulated sporocysts (10–11 × 7.0 μm) were found in the lamina propria of small intestines of cats killed 6 and 7 days postinoculation (PI). Interferon gamma gene knockout (KO) mice were orally inoculated with sporocysts from experimentally infected cats, and their tissues were examined histologically; sarcocysts were found in 5 KO mice killed 87, 115, 196, 196, 196 days PI, but no stages were seen in 5 KO mice 10, 14, 14, 18, and 39 days PI. Bradyzoites were released from intramuscular sarcocysts of a KO mouse killed 115 days PI and orally inoculated into 5 KO mice. No stage of Sarcocystis was found in any organ (including intestinal lamina propria) of KO mice killed 4, 8, 81, 190, and 190 days PI, confirming that the definitive host is required to complete the life cycle even in the case of immunodeficient mice. This is the first confirmation of S. muris infection in a naturally infected cat anywhere.

Despite the availability of many parasitological methods for detection of Cryptosporidium and Isospora (Cystoisospora) belli in fecal samples, there are uncertainties about the accuracy of these techniques in laboratory practice. In this study, 27 formalin-fixed positive stool samples for Cryptosporidium and 15 for I. belli were analyzed by 2 concentration methods, sedimentation by centrifugation (SC) and formalin–ethyl acetate (FE), and by 3 tintorial techniques, modified Ziehl-Neelsen (ZN), safranin (SF), and auramine (AR). No significant differences were observed on Cryptosporidium identification between concentration methods, while a significantly higher number of I. belli oocysts (P < 0.0001) was detected in fecal smears concentrated by the SC than by the FE method. Fecal samples processed by FE produced a median oocyst loss to the fatty ring of 34.8% for Cryptosporidium and 45.4% for I. belli. However, FE concentration provided 63% of Cryptosporidium and 100% of I. belli slides classified as superior for microscopic examination. Regarding the efficiency of staining methods, a more significant detection of Cryptosporidium oocysts was observed in fecal smears stained by ZN (P < 0.01) or AR (P < 0.05) than by the SF method. Regular to high-quality slides for microscopic examination were mostly observed in fecal smears stained with AR or ZN for Cryptosporidium and with SF or ZN for I. belli. This study suggests a great variability in oocyst power detection by routine parasitological methods, and that the most frequent intestinal coccidians in humans have specific requirements for concentration and staining.

Seven cases of parasitism by Strongyloides cebus were identified in Lagothrix cana from Brazil. Aspects of the clinical presentation, treatment, pathology, and parasitic biology of these infections are described. Moderate to severe disease was observed, requiring hospitalization of 3 primates, and diarrhea was the most common clinical sign described. One L. cana individual died, for which ulcerative enteritis was the major finding upon histopathological analysis. The use of ivermectin in these atelids was safe and effective against the parasite. Parallel attempts to experimentally infect gerbils with the parasite failed. Lagothrix cana is presented as a new host for S. cebus. The evidence that Strongyloides infections are common in nonhuman primates under free-living conditions, and even more prevalent in captive animals, likely represents a neglected problem.

Isospora bors n. sp. (Apicomplexa: Eimeriidae) is described from 6 of 30 (20%) Baiuch rock gecko Bunopus tuberculatus Blanford in Saudi Arabia. Sporulated oocysts are subspheroidal to spheroidal, 18 × 16 (17–20 × 15–17) μm, with a bilayered, smooth, yellow-orange wall, without striae or micropyle. Polar body and oocyst residuum, both absent. Sporocysts are ovoidal, 10 × 7 (9–11 × 6–9) μm, with a Stieda body and sporocyst residuum. Endogenous stages developed in the cytoplasm of epithelial cells of the small intestine and above the host cell nucleus.

Strongyluris dracocola n. sp. from the intestine of Lophognathus temporalis collected in Papua New Guinea is described and illustrated. Strongyluris dracocola n. sp. represents the 32nd species assigned to the genus and the sixth from the Australo-Papuan region. It can be easily separated from the other Australo-Papuan species because it is the only species to have an unpaired median papilla adjacent to the sucker.

Hepatozoon species are apicomplexan parasites that infect blood cells and viscera of terrestrial vertebrates. One species, Hepatozoon clamatae, primarily infects green frogs, Rana clamitans, whereas another, Hepatozoon catesbianae, primarily infects bullfrogs, Rana catesbeiana, although both species of parasite are capable of infecting either species of frog. The aim of this study was to determine whether the basis for this partial host specificity is manifested at the gamont, or intraerythrocytic, stage of the parasite's life cycle. Blood was drawn from infected frogs and treated in vitro with a saline solution to induce intracellular gamonts to emerge from host erythrocytes. This treated blood was added to in vitro samples of uninfected blood of green frogs and bullfrogs. After 1 hr, samples were analyzed to determine the level of re-entry of the parasites into uninfected erythrocytes. Results obtained using multiple combinations of donor and recipient frogs indicate that extracellular gamonts of both parasite species do not exhibit preference for erythrocytes of 1 frog species over those of another. These results suggest that the basis for the observed host specificity is not determined at the gamont stage and is more likely dependent on another stage in the parasite life cycle.

Pterygodermatites (Mesopectines) niameyensis n. sp. is described from Mastomys natalensis in Niamey/Niger (West Africa). It differs from other species of same subgenus by the morphology of the head, which presents 4 simple cephalic papillae and nearly axial oral opening, a number of caudal papillae, precloacal cuticular formations, and the spicule length/body length ratio. Scanning electron microscopy shows the presence of 2 pairs of lateral sensory structures for male worms.

A new species of Spirura is described from the stomach of Heliosciurus gambianus and Xerus erythropus (Sciuridae). Considering the number of preanal papillae of males, Babero (1973) and Giannetto and Canestri Trotti (1995) proposed the subdivision of the genus into 2 groups; those with 4 pairs of preanal papillae (25 species) and with more than 4 pairs of preanal papillae (4 species). Spirura mounporti n. sp. belongs to the second, with 5 pairs of preanal papillae, and differs from Spirura infundibuliformis (McLeod, 1933) Anderson et al., 1993, Spirura zapi (Erickson, 1938) Chabaud et al., 1965, Spirura leiperi Gupta and Trivedi, 1985, and Spirura michiganensis Sandground, 1935 in the number of pairs of pre-cloacal papillae. The new species further differs from other species of the genus in having 21 caudal papillae, in the ratio of spicules:body length, and in its morpho-anatomical characters.

Staphylocystoides gulyaevi n. sp. is described based on specimens obtained from the dusky shrew Sorex monticolus collected on Sukkwan Island, southeast Alaska. Staphylocystoides gulyaevi n. sp. is compared with other North American members of the genus having 10 rostellar hooks. The new species is morphologically similar to Staphylocystoides parvissima and Staphylocystoides asketus. The uterus in S. gulyaevi n. sp. develops much more rapidly, and a well-developed uterus appears abruptly after it is barely visible in a previous proglottid. In S. parvissima the uterus grows gradually, and its early development is seen in several proglottids. At the level of pre-gravid proglottids the uterus of S. gulyaevi n. sp. occupies only the middle field of the proglottid, while in S. parvissima it fills the whole proglottid including lateral fields. The rostellar hooks in the new species are significantly smaller in size than in S. asketus. Additionally, the new species has fewer proglottids than S. asketus, while having a similar strobila length. Molecular comparison, using 3 genes (28s rDNA, cox1, and nad1), between S. gulyaevi n. sp. and S. parvissima, further corroborates the status of S. gulyaevi n. sp. as a new species. The new species is the seventh species of Staphylocystoides found in North America and the first cestode or any helminth reported from shrews in southeast Alaska.

Within genetically diverse infections of malaria parasites (Plasmodium spp.), the relative proportions of genetic clones in the vertebrate host's blood can influence clonal competition, transmission success, gametocyte sex ratio, and virulence. Clonal proportions depend on establishment success of each clone when they enter a new host and on subsequent differences in rates of asexual replication and clearance. Both of these life history traits could be influenced by clone genotype. To assess genetic (clonal) influences on both establishment success and later changes in relative proportion for the lizard malaria parasite Plasmodium mexicanum, 7 naturally infected fence lizards harboring a single clone of P. mexicanum served as donors to initiate replicate experimental infections containing each of the clones and combinations of 2 clones. Measured were relative establishment success of each clone, change in relative proportions over time, and rate of increase of parasite density and total parasitemia. Relative clonal proportions were determined using microsatellite markers. Rates of increase in the parasitemia and degree of change in relative proportions were not correlated, so both rapidly and slowly growing infections could show either little or substantial change in clonal proportions over time. There was a significant clone effect on establishment efficiency but not on later changes in relative proportions. These results argue for a combination of genetic and environmental (host) effects on the success of P. mexicanum clones in genetically complex infections. The maintenance of genetic variation for establishment success, but not subsequent replication rate or shifts in relative proportion, suggests trade-offs between these traits during life history evolution of malaria parasites.

Aspidodera kinsellai n. sp. (Heterakoidea: Aspidoderidae) from the 9-banded armadillo, Dasypus novemcinctus, is herein described. This nematode occurs from Costa Rica north through central Mexico where it can be found causing co-infections with Aspidodera sogandaresi. Aspidodera kinsellai n. sp. can be discriminated from this and all other species in the family based on 3 key features, including (1) conspicuous lateral grooves with no lateral alae starting immediately after the hood and terminating at the cloacal/anal region; (2) long hoods in both male (360 μm) and female (401 μm), and (3) a relatively long (152 μm) terminal spine or terminus that gradually tapers to a point from the last pair of papillae. This is the 18th recognized species of the family and the 3rd in the genus present outside of South America. A phylogenetic analysis of the species in the genus with the use of the mitochondrial partial genes cytochrome C oxidase subunit 1 (cox1), the ribosomal large subunit (rrnL), and the internal transcriber spacer (ITS) shows that 2 species of Aspidodera may have entered into North America from the south via 2 independent events.

Gyrodactylus mediotorus n. sp. is described from the body, fins, and buccal cavity of the spottail shiner, Notropis hudsonius (Cyprinidae) from the St. Lawrence River, Quebec, Canada. Gyrodactylus mediotorus n. sp. is the first species of Gyrodactylus Nordmann, 1832 described from N. hudsonius and is characterized by large hamuli, large medial process of the ventral bar, narrow linguiform ventral bar membrane, large anterolateral processes, and marginal hooks with long shafts and distinctly shaped sickle. The species that most resembles Gyrodactylus mediotorus n. sp. is Gyrodactylus protuberus Rogers and Wellborn, 1965 described from the stargazing shiner, Notropis uranoscopus Suttkus, 1959. The 2 species can be differentiated based on the larger hamuli (68.4 vs. 64) and ventral bar (38.4 vs. 24) of Gyrodactylus mediotorus n. sp. and the shape of the marginal hooks which for Gyrodactylus mediotorus n. sp. has a slightly larger toe and a point which is not as angled. The morphological description is supplemented with 436 sequenced base pairs of the 18S gene (including the V4 region) as well as 1,041 sequenced base pairs spanning the complete ITS-1, 5.8S, and ITS-2 regions. BLAST (Basic Local Alignment Search Tool) searches failed to provide any close matches for either regions of DNA, with Gyrodactylus colemanensis infecting Salvelinus fontinalis being the most genetically similar for both the 18S (∼91%, JF836090) and ITS (∼84%, JF836142) rDNA regions. Gyrodactylus mediotorus n. sp. has been found infecting spottail shiners in the St. Lawrence River in low prevalence and intensities periodically over the last 15 yr.

During an inventory of parasites of anurans in Occidental Mexico, an apparently undescribed species of Halipegus was found under the tongue of Rana psilonota Webb, 2001. The objective of this study is to describe this new species. Halipegus psilonotae differs from all other congeners by the combination of the following characters: parasite under the tongue of frogs, body size small, ventral sucker representing 0.19–0.2 of body length, ovary smaller than testes, egg filament short (27.5–40).

In the order Chiroptera, more than 30 trypanosome species belonging to the subgenera Herpetosoma, Schizotrypanum, Megatrypanum, and Trypanozoon have been described. The species Trypanosoma cruzi, Trypanosoma cruzi marinkellei, and Trypanosoma dionisii are the most common in bats and belong to the Schizotrypanum subgenus. Bats from 2 different biomes, Pantanal and Amazonia/Cerrado in the state of Mato Grosso, Brazil, were evaluated according to the presence of trypanosome parasites by means of hemoculture and PCR in primary samples (blood samples). A total of 211 bats from 20 different species were caught and the trypanosome prevalence, evaluated through hemoculture, was 9.0% (19), 15.5% (13), and 4.8% (6) in the municipalities of Confresa (Amazonia/Cerrado biome) and Poconé (Pantanal biome). Among the 123 primary samples obtained from the bats, only 3 (2.4%) were positive. Phylogenetic analysis using trypanosomatid barcoding (V7V8 region of SSU rDNA) identified all the isolates and primary samples as T. c. marinkellei. The sequences of the isolates were segregated according to the bat host genus or species and suggest that co-evolutionary patterns exist between hosts and parasites. Further studies in different Brazilian regions and biomes need to be conducted in order to gain real understanding of the diversity of trypanosomes in bats.

The helminth parasite fauna of the hylid frog Pseudacris hypochondriaca in several localities along the Baja California Peninsula in northwestern Mexico is presented. The helminth fauna consists of 4 species of nematodes (Oswaldocruzia pipiens, a larval form of an Ascaridid, 2 new species belonging to the genera Rhabdias and Cosmocercoides), and 1 species of digenean (Gorgoderina sp.). The new species of Rhabdias represents the 88th species assigned to the genus and the third species described from Mexican anurans. Also, the species of Cosmocercoides represents the 20th species assigned to the genus and the first representative of this genus described from Mexico.

Between September 1991 and March 1993, 25 moth skinks (Lipinia noctua) were collected from various localities on the Cook Islands, Fiji, Papua New Guinea (PNG), and Vanuatu and examined for coccidians. In addition, a single Roux's lipinia skink (Lipinia rouxi) was collected from PNG and examined for coccidia. Sixteen (64%) L. noctua were found to harbor 2 new eimerians, and L. rouxi harbored another new Eimeria sp. Oocysts of Eimeria lipinia n. sp. from 9 (36%) L. noctua from the Cook Islands, Fiji, and PNG were subspherical with a bilayered wall and measured (L × W) 18.6 × 16.9 μm, with a L/W ratio of 1.1. Both micropyle and oocyst residuum were absent, but a polar granule was present. Oocysts of Eimeria melanesia n. sp. from 6 (24%) L. noctua from Fiji and Vanuatu and a single L. rouxi from PNG were subspherical to ellipsoidal with a bilayered wall and measured 19.8 × 17.5 μm, and L/W was 1.1. Both micropyle and oocyst residuum were absent, but a single or fragmented polar granule was present. Oocysts of Eimeria lessoni n. sp. from 1 (4%) L. noctua from PNG were cylindroidal with a bilayered wall and measured 28.1 × 15.7 μm, and L/W was 1.8. Both micropyle and oocyst residuum were absent, but a single polar granule was present. These represent the third report of Eimeria spp. reported from any host on PNG and the only coccidians, to our knowledge, ever described from L. noctua and L. rouxi and from the Cook Islands and Vanuatu.

Pigmented hemosporidian parasites that do not exhibit erthyrocytic schizogony, and infect birds, chelonians, and squamates, have been classified in various genera over time. These classifications have reflected vertebrate hosts, insect vectors, and variations in morphology and life history observed in representative species. Side-necked turtles (Podocnemis spp.) from the Peruvian Amazon were screened for hemoparasites and 2 species of hemosporid parasites infecting these hosts were observed. Molecular phylogenetic analysis of these new isolates, along with parasites from lizards, a snake, and a variety of Haemoproteus species from birds from both the Haemoproteus and Parahaemoproteus subgenera, strongly support the separation of the non-avian parasites into a separate genus. The name with precedent for this group is Haemocystidium Castellani and Willey 1909, and we propose that subgeneric classification of Haemocystidium and Simondia be applied to parasites of squamates and chelonians, respectively. We offer a description of Haemocystidium (Simondia) pacayae n. sp. and a redescription of Haemocystidium (Simondia) peltocephali (Lainson and Naiff 1998, n. comb.) Morphologically, the parasites are quite similar, with H. pacayae slightly more elongated than H. peltocephali. The discovery and identification of parasite species is urgent, especially in endangered species and wildlife inhabiting rapidly declining ecosystems such as the Amazon.

Tetraphyllidean cestodes of the genus Trilocularia have been reported from Squalus acanthias throughout this shark's global distribution, occupying both the stomach and spiral intestine. This study investigated whether variation seen in microthrix form among specimens within this host species is indicative of interspecific variation or is attributable to developmental transformation of a single cestode species. Sequence data for the 2 nuclear genes 28S rDNA (D1–D3) and ITS1, and the mitochondrial gene 16S rDNA, were generated for 22 specimens of Trilocularia; 3 from the stomach and 19 from the spiral intestine, including individuals exhibiting each of the 3 spinithrix forms found. Sequence data for 22 specimens were identical for the 2 nuclear genes. Some variation was seen in the mitochondrial gene but maximum likelihood analysis revealed no pattern with either site or microthrix type, suggesting microthrix variation may be developmental. To explore the developmental hypothesis further, a total of 118 juvenile worms from the stomach and 124 from the spiral intestine were collected from S. acanthias off the coast of Rhode Island and examined with either scanning electron microscopy (SEM) or light microscopy. SEM revealed differences in microthrix form between worms from the 2 sites. Of the stomach and spiral intestine worms examined, respectively, 98% versus 30% were scolopate, 2% versus 47% were aristate gladiate, and 0% versus 15% were lingulate in microthrix form. In addition, 3 of the 77 specimens from the spiral intestine examined with SEM exhibited mixtures of spinitriches. ANOVAs showed significant differences in the morphometrics of stomach worms, when compared to spiral intestine worms, as well as significat differences in the scolex width:below scolex width ratio of worms with scolopate spinitriches when compared to those with aristate gladiate or lingulate spinitriches. In combination, these data suggest that microthrix form may change over the course of development, indicating that caution should be exercised when interpreting microthrix patterns in the context of species designations.

Eight species of Neoechinorhynchus were reported from Australian waters. Neoechinorhynchus vittiformis n. sp. is described from Eleutheronema tetradactylum (Shaw). It can be distinguished from all its congeners by the following combination of characters: long cylindrical trunk without cuticular plaques, globular proboscis, proboscis armature with the anterior circle of hooks larger with simple roots and the middle and posterior hooks the same size and smaller, short neck, lemnisci nearly equal, almost reaching the anterior testis which is more than half the length of the posterior testis. Neoechinorhynchus (Neoechinorhynchus) bryanti n. sp., described from Liza subviridis (Valenciennes), also with an elongated trunk, can be distinguished from its congeners by the combination of a wider anterior trunk without cuticular plaques, a relatively long conical neck, a subglobular proboscis having anterior hooks with manubria, the hooks becoming gradually smaller posteriorly, the lemnisci not reaching level of testes and the anterior testis being longer than posterior testis. Neoechinorhynchus sp. resembled Neoechinorhynchus aldrichettae Edmonds, 1971 but had a rectangular-shaped proboscis with larger anterior hooks. New host and locality records were presented for N. aldrichettae, Neoechinorhynchus (Hebesoma) agilis (Rudolphi) and Neoechinorhynchus tylosuri Yamaguti, 1939. No additional specimens of either Neoechinorhynchus ningalooensis Pichelin and Cribb, 2001 or the species inquirenda, Neoechinorhynchus magnus Southwell and Macfie, 1925, were available for study. Of the 8 putative species listed here, 5 (N. [N.] bryanti, N. magnus, N. ningalooensis, N. vittiformis, and Neoechinorhynchus sp.) are endemic to Australian waters. By comparison with the North American fauna the Australian fauna was considered impoverished. The morphological and zoogeographical similarities within the group of 8 long, slender neoechinorhynchid species found in the African, Indo Malayan, and Western Pacific Regions, including the 3 found in Australia, may reflect a degree of evolutionary affinity.

A new species, Crepidostomum affine n. sp., is described from Hiodon tergisus in Mississippi, and morphological data are provided for Crepidostomum auritum from Aplodinotus grunniens in Mississippi and for Crepidostomum illinoiense from Hiodon alosoides in Minnesota. The new species is most similar morphologically to C. illinoiense, but has a shorter intertesticular space, measuring 0–74 μm (mean = 19.3 ± 23.1 SD in 73 specimens) compared with 0–229 μm (mean = 57.3 ± 56.7 SD in 34 specimens), and the distance between the ovary and the anterior testis is relatively shorter in the new species, representing 2.6–7.9% of overall body length compared with 4.1–12.4% in C. illinoiense. Fragments of nuclear ribosomal as well as mitochondrial DNA are compared among C. affine n. sp., C. illinoiense, C. auritum and Crepidostomum cornutum. Crepidostomum affine n. sp. and C. illinoiense are most similar, having between 19 and 20 variable bases (1.29–1.36%) in the amplified nuclear ribosomal RNA fragment comprising the complete ITS2 spacer and partial 28S gene, and between 35 and 39 variable bases (8.62–9.61%) in the amplified fragment of the COI region. Specimens of C. illinoiense from the Missouri River in North Dakota and Red Lake River in Minnesota differed by 1 base (0.07%) in the rRNA fragment and 4 bases (0.95%) in COI fragment. Crepidostomum cornutum and C. auritum also have 19 (1.29%) variable bases in the amplified ITS2 and partial 28S regions and 50 (12.32%) variable bases in the amplified COI region. Both C. cornutum and C. auritum demonstrated much greater levels of differences compared to C. affine n. sp. These results add to previously published data reporting species of fish digeneans that might be endemic to the Pearl and Pascagoula river basins in Mississippi.

Oral administration of Toxoplasma gondii oocysts to cats (i.e., monoxenous transmission) typically induces patent infections in fewer than half of test subjects. In the present study, oral administration of T. gondii oocysts to 5 kittens induced a patent infection in 2 of them, but only 1 kitten shed enough oocysts to enable further study. Those monoxenously-produced oocysts were administered to another kitten, which produced a second generation of monoxenous oocysts, and then those were used to induce a third generation of monoxenous oocysts. These results provide a rationale to develop a strain of T. gondii that has efficient direct transmission. The isolate of T. gondii that was able to be passaged in this manner has been designated the Dubey strain and cultured tachyzoites have been donated to a repository.

Ecto-adenosinedeaminase (E-ADA) plays an important role in the production and differentiation of blood cells as well as in the control of extracellular adenosine levels. Infectious diseases can influence the synthesis of new cells or cause cell destruction, as occurs in canine rangeliosis, which results in anemia, thrombocytopenia, leukocytosis, and/or leukopenia. Thus, this study aimed to evaluate E-ADA activity in sera, erythrocytes, lymphocytes, and adenosine levels in sera samples of dogs infected by Rangelia vitalii. Twelve animals were divided into 2 groups: noninfected (n = 5) and infected by R. vitalii (n = 7). Animals were infected with 2 ml of blood containing the parasite, and parasitemia was estimated daily for 20 days by microscopic examination of peripheral blood smears. Blood collection was performed on days 0, 10, and 20 post-infection (PI) in order to evaluate the evolution of the disease. The blood collected was used to assess the activity of E-ADA. We observed an increase of E-ADA activity in sera (day 20 PI) and erythrocytes (days 10 and 20 PI) in the infected group (P < 0.05). E-ADA activity in lymphocytes was decreased on day 10, when the parasitemia was high, and increased after 20 days, when the number of circulating parasites was low. HPLC measured adenosine levels in the serum and found a reduction on days 10 and 20 PI. In conclusion, our results showed that E-ADA activity was altered in sera, lymphocytes, and erythrocytes of dogs experimentally infected by R. vitalii as well as the serum concentration of adenosine. These alterations may contribute to the pathogenesis of anemia and immune response in infected dogs.

In this study, we investigated oysters, Crassostrea virginica, from Laguna Madre in South Texas, where a 45-yr old study recorded metacercarial infections of the echinostomatid trematode, Acanthoparyphium spinulosum, an Asian relative of which, Acanthoparyphium tyosenense, has been associated with human infections via the ingestion of raw mollusks. In an effort to examine the base-line infection parameters of Acanthoparyphium sp. in oysters, we examined the effect of distance from the shoreline, which is the habitat of the first intermediate host snail, Cerithidea pliculosa, as well as temporal changes in oyster infection levels, by conducting quarterly collections of oysters during a year. We found that almost all oysters (prevalence = 97.8–100%) were infected regardless of distance to the shoreline and season. However, the abundance of metacercariae was significantly higher close to the shoreline, while no significant temporal changes could be detected. In addition to the echinostomatid, we found a high abundance of the metacestode Tylocephalum sp. and the presence of 4 other metazoan parasites. None of the infections seemed to incur significant tissue damage to the oysters. Our study shows that at least locally, recreational harvesters of oysters may be exposed to Acanthoparyphium sp. Future studies should examine oysters from snail host habitats in the Gulf of Mexico, and the potential zoonotic risk of Acanthoparyphium sp. should be evaluated using experimental infections of animal models.

Avian hemosporidian parasites are a genetically diverse group of parasites with a near cosmopolitan distribution. Over the past 2 decades, several PCR protocols have been designed to detect these parasites. The majority of these protocols amplify part of or the entire mitochondrial cytochrome b gene. However, many of these protocols co-amplify 2 genera (Haemoproteus and Plasmodium), making it impossible to determine which genus is amplified without post-PCR analysis. A uniform database (MalAvi), containing sequences amplified with the primers HAEMF and HAEMR2, has been developed to increase comparability across studies. We analyzed sequences from the MalAvi database and new sequences and found that digestion with EcoRV could be used to distinguish Haemoproteus from the majority of Plasmodium sequences. In addition, we tested 220 wild birds from Costa Rica and the United States for avian hemosporidians and assessed the ability of EcoRV to distinguish these 2 genera. Thirty-six positive samples were sequenced to confirm the restriction profiles, and we also analyzed 63 new hemosporidian sequences from ongoing studies in the United States for the restriction site. Among these new samples, all of the 85 Haemoproteus (subgenus Parahaemoproteus) and 14 Plasmodium were distinguishable. Overall, 887 of 898 (98.8%) sequences from our studies and the MalAvi database were assigned to the correct genus. Of these samples, all Haemoproteus samples were correctly identified and all but 11 Plasmodium samples were correctly identified by the EcoRV assay. Overall, this restriction enzyme protocol is able to quickly and efficiently classify these 2 genera of avian malarial parasites and would be useful for researchers interested in identifying parasites to genus-level, studies focused on sequence analysis of only a single genus, or for detecting co-infections that would need cloning prior to sequence analysis.

A leech was found parasitizing the ocular orbit of a common redstart captured during a faunistic survey of Antikythira in the Aegean Sea during the spring migration of 2012. Morphological and molecular characterizations placed the leech in the mucous-membrane specific leech family Praobdellidae and definitively as the species Parapraobdella lineata. This is the first record of any leech parasitizing a passerine bird, Phoenicurus phoenicurus, and the first of a praobdellid leech on any avian host.

Felids are important in the epidemiology of Toxoplasma gondii because they are the only hosts that can excrete the environmentally resistant oocysts in their feces. Cats acquire T. gondii infection in nature by ingesting tissues of small mammals and birds. Serum samples of 223 feral marsupials and 174 feral rodents captured in 7 segments of the Atlantic Forest of the State of Pernambuco, northeastern region of Brazil, and in urban areas of the municipality of Recife were examined for antibodies to T. gondii by the modified agglutination test (MAT). Antibodies (MAT ≥ 25) were found in 6.7% (15 of 223) of the marsupials and 5.7% (10 of 174) of the rodents. No association was observed between seropositivity in marsupials or rodents and sex, age, or different areas of collection (P > 0.05). This is the first study on the seroprevalence of T. gondii in marsupials and rodents performed in the Atlantic Forest of the northeastern region of Brazil. The presence of antibodies to T. gondii are reported for the first time in long-furred woolly mouse opossum (Micoureus demerarae), murine mouse opossum (Marmosa murina), brown four-eyed opossum (Metachirus nudicaudatus), and gray short-tailed opossum (Monodelphis domestica).

The persistence of Giardia, Cryptosporidium, Rotavirus, and Adenovirus in samples of raw and treated sewage collected monthly in 2010 at the Biological Wastewater Treatment Plant of Ribeirão Preto, SP, Brazil, was analyzed. The USEPA Method 1623 was used to detect and quantify Giardia and Cryptosporidium. An enzyme immunoassay was carried out to test Rotavirus and Adenovirus antigen optical density (Rotascreen® and Adenoscreen®). The results show a significant decrease in the concentrations of Giardia, Rotavirus and Adenovirus (P < 0.05) and a trend of decreasing Cryptosporidium densities, without statistical significance. Giardia concentrations ranged from 120 to 2,200 cysts/L in raw sewage and from 0.45 to 3.5 cysts/L in treated sewage. Cryptosporidium concentration ranged from undetectable to 28.9 oocysts/L in raw sewage and undetectable to 1.05 oocysts/L in treated sewage. Rotavirus presented absorbance values that ranged from 1.17 ± 0.81 in raw sewage to 0.46 ± 0.32 in treated sewage. Adenovirus, in turn, presented absorbance values of 0.64 ± 0.20 in raw sewage and of 0.45 ± 0.04 in treated sewage. There was no significant seasonal tendency observed in the distribution of protozoa (oo)cysts and in the viral antigen density in the monthly sewage samples during 2010 (P > 0.05). Even though these pathogenic agents decreased after treatment, the remaining loads observed in treated sewage can reach the watercourses receiving it. Giardia, Cryptosporidium, Rotavirus, and Adenovirus are pathogens with very low infectious doses, representing a public health risk especially for vulnerable groups, such as children living near these watercourses and homeless people using this water for various purposes. Studies addressing the environmental persistence of opportunistic pathogens in watercourses are hugely important in the public health sphere, especially in developing countries, where economic, social, cultural, and environmental factors still persist that are favorable to population's exposure to diarrhea-causing agents.

The present study was conducted to investigate the prevalence and genotypes of Cryptosporidium in bats. A total of 247 bats, belonging to Rhinolophus sinicus, Rousettus leschenaultia, Aselliscus stoliczkanus, and Hipposideros fulvus, were collected in Yunnan Province, Southwestern China, and the intestinal tissues were examined for Cryptosporidium infection by PCR amplification of the small subunit ribosomal RNA (SSU rRNA). The overall infection rate was 7.7% (95% CI, 4.5 to 11.0%), with R. sinicus having the highest level at 9.5% (95% CI, 2.8 to 16.1%) followed by A. stoliczkanus at 7.8% (95% CI, 2.2 to 18.9%), H. fulvus at 7.2% (95% CI, 1.1 to 13.4%), and R. leschenaultia at 5.7% (95% CI, 1.2 to 15.7%). DNA sequence and phylogenetic analyses based on SSU rRNA revealed the presence of 2 novel genotypes, designated as Cryptosporidium bat genotype I in A. stoliczkanus and R. sinicus and Cryptosporidium bat genotype II in R. leschenaultia, R. sinicus, and H. fulvus. This is the first report of Cryptosporidium genotypes in bats. Further biological and genetic characterization is needed to determine the relationship of the 2 novel genotypes to established Cryptosporidium species–genotypes.

Fifty lemon sharks, Negaprion brevirostris, were captured in a shallow, mangrove-fringed shark nursery at Bimini, Bahamas and examined for the presence of skin-dwelling ectoparasitic monogenoids (Monogenoidea). Sixteen sharks were infected by Dermophthirius nigrellii (Microbothriidae); the youngest host was estimated to be 3- to 4-wk-old. Infection prevalence, mean intensity, and median intensity (0.32, 2.63, and 2.0, respectively, for all sharks) were not significantly different between neonates (estimated ages 3- to 10-wk-old) and non-neonatal juveniles (estimated ages 1- to 4-yr-old), suggesting that soon after parturition lemon sharks acquire infection levels of D. nigrellii matching those of juvenile conspecifics. Monogenoids were only found on the trailing portion of the first and second dorsal fins and upper lobe of the caudal fin. The prevalence of D. nigrellii was highest on the first dorsal fin; however, the mean and median intensities of D. nigrellii were similar between fins in all but 1 case. These results raise important husbandry implications regarding the practice of preferentially seeking neonatal and other small lemon sharks for captivity.