Two species of bufonid frogs from Borneo were examined for helminths: Phrynoidis juxtasper (n = 5), and Ingerophrynus divergens (n = 4). We found 2 species of Nematoda, Cosmocerca ornata and Seuratascaris numidica, and 1 species of Acanthocephala, Pseudoacanthocephalus bufonis. Seuratascaris numidica was the only helminth infecting both bufonid species. The most numerous helminth (n = 15) was S. numidica in P. juxtasper. The 2 species of Bufonidae are parasitized by generalist helminths that also infect other species of anurans. Four new host records are reported.

Falcaustra samarensis n. sp. (Ascaridida, Kathlaniidae) from the intestines of Megophrys stejnegeri Taylor 1920 (Anura, Megophryidae) is described and illustrated. Falcaustra samarensis n. sp. represents the one hundred fourth species assigned to the genus and the thirty-seventh Oriental species. It is distinguished from other Oriental species by the pattern of caudal papillae (8 precloacal, 2 adcloacal, 10 postcloacal, and 1 median), length of spicules (2,050–3,300 µm) and presence of 1 pseudosucker. Megophrys stejnegeri was also found to harbor 2 additional species of Nematoda, adults of Aplectana ranae and Batrachostrongylus longispiculus. Megophrys stejnegeri represents a new host record for each of these helminth species.

Three species of Polypedates frogs (Rhacophoridae) from Borneo, Malaysia, were examined for helminths: Polypedates colletti (n = 5), P. macrotis (n = 8), and P. otilophus (n = 5). We found 3 species of Nematoda: Cosmocerca ornata, Raillietnema rhacophori, and Physalopteroides sp. Cosmocerca ornata was the only helminth infecting all 3 rhacophorid species. The most numerous helminth (too numerous to count) was R. rhacophori in P. otilophus. The 3 species of Polypedates are parasitized by generalist helminths that also infect other species of anurans. Four new host records are reported.

Horsehair worms, such as Paragordius varius, exhibit knotting behavior that may serve various functions such as water regulation, mate facilitation, and predator avoidance. Previous studies have found knots consisting only of males, suggesting that this behavior may be mediated by an aggregation pheromone. We conducted a quantitative field study to determine the relative number and size of adult P. varius that occur singly and in knots in a creek known to have a large number of adults in September of 2018. We collected 96 horsehair worms; all were male and associated with vegetation. We found significantly more adult male P. varius occurring singly than in knots and found no significant difference in their length or dry weight. Behavioral assays in the lab can help determine the possible presence and function of hairworm aggregation pheromone.

Between March 2016 and March 2018, 52 golden topminnows, Fundulus chrysotus, were collected in the Arkansas (n = 5), Ouachita (n = 20), Red (n = 21), and St. Francis (n = 6) river drainages of Arkansas and examined for parasites. Twenty-three (44%) were infected/infested, including 1 (2%) with Calyptospora funduli, 4 (8%) with Myxobolus sp., 9 (18%) with Salsuginus sp., 2 (4%) with Homalometron sp., 2 (4%) with metacercaria of Clinostomum marginatum, 4 (8%) with Posthodiplostomum minimum, 5 (10%) with immature Proteocephalus sp., 4 (8%) with larval Eustrongylides sp., 5 (10%) with acanthocephalan cystacanths, 2 (4%) with Leptorhynchoides sp., 1 (2%) with Neoechinorhynchus sp., and 1 (2%) with Lernaea cyprinacea. Six (12%) topminnows harbored multiple infections. We document 4 new host and 3 new distributional records; the Homalometron sp. appears to be new, and the samples of Myxidium likely represent at least 1, if not 2, previously undescribed species, but both require additional specimens for a description.

Three species (1 new) of HaliotrematoidesKritsky, Yang, and Sun, 2009 (Dactylogyridae), are described from the gill lamellae of porgies, Calamus spp. (Perciformes: Sparidae), from the northern Gulf of Mexico off Florida: Haliotrematoides parvicirrus (Zhukov, 1983) Kritsky, Yang, and Sun, 2009, from littlehead porgy Calamus proridens Jordan and Gilbert and knobbed porgy Calamus nodosus Randall and Caldwell (both new host records); Haliotrematoides bostryx n. sp. from C. proridens (type host), C. nodosus, jolthead porgy Calamus bajonado (Bloch and Schneider), and grass porgy Calamus arctifrons Goode and Bean; and Haliotrematoides mediohamus (Zhukov, 1983) Kritsky, Yang, and Sun, 2009, from C. proridens, C. nodosus, and sheepshead porgy Calamus penna (Valenciennes) (all new host records). Locations from which H. parvicirrus and H. mediohamus were collected in the northern Gulf of Mexico represent new geographic records for these species.

Ten honey badgers (Mellivora capensis wilsoni) and 10 West-Asian blunt-nosed vipers (Macrovipera lebetina obtusa) were collected from the Almadeena district North Basrah governorate, southern Iraq, and examined for helminths. Cystacanths and 2 adult specimens of an acanthocephalan Oligacanthorhynchus sp. were found, and these represent new host records and a new record for Iraq. The specimens could be distinguished from all other species of Oligacanthorhynchus in having a proboscis armature of 36 hooks arranged in 12 rows of 3 hooks without large manubria, the largest hooks (circle 1) up to 120 µ m long. There was, however, insufficient material to adequately describe the putative new species. Honey badgers are opportunistic carnivores that include snakes in their diet, supporting the contention that the vipers are paratenic hosts and honey badgers are the definitive hosts for this oligacanthorhynchid.

Spiny softshell turtles (Apalone spinifera), common snapping turtles (Chelydra serpentina), and red-eared sliders (Trachemys scripta elegans) were surveyed for leeches at 16 sites across Texas, U.S.A., from March to December of 2017. Five species of leeches were found (3 from 15 A. spinifera sampled, 4 from 9 C. serpentina sampled, and 3 from 55 T. scripta elegans), representing 3 new host records and 1 new locality record. Leech abundance was also compared to water parameters (ammonia, carbon dioxide, chloride, dissolved oxygen, hardness, nitrite, nitrate, pH, salinity, temperature, and turbidity) and qualitative environmental variables (vegetation, sediment, latitude, longitude, season, and water body) through principle components analysis, stepwise regression, and model selection. We found significant effects of sediment composition and seasonality on leech abundance. This study adds novel data on leech–host associations, distributions, and diversity in Texas.

Eighty-two green lizards, Lacerta viridis (Laurenti, 1768), from different locations of Bursa, Turkey, were examined for helminths. Two species of Cestoda, Mesocestoides sp. (as tetrathyridium) and Oochoristica tuberculata, and 4 species of Nematoda, Oswaldocruzia filiformis, Skrjabinelazia hoffmanni, Skrjabinelazia taurica, and Skrjabinodon medinae, were found. Lacerta viridis is parasitized by generalist helminths that also infect other lizards. Parasite lists for other Turkish lacertid lizards are given.

We describe a monogenean species new to science belonging to Markewitschiana, a genus characterized by the absence of anchors. Markewitschiana agdazensis n. sp. parasitizes the gills of Luciobarbus pallaryi (Cyprinidae) in Morocco. The newly described species is characterized by the presence of 7 pairs of hooks; 1 pair of “ventral structures” resembling vestiges of anchors; bar cruciform-shaped; male copulatory organ a long tube, beginning with a bulb, accessory piece tubular and articulated at the base of the MCO; and sclerotized vagina elongated with enlarged opening. This is the first report of a species of Markewitschiana outside Asia and on the gills of its fish host; individuals of this genus are usually found in the nasal cavities of their hosts.

Camallanus philippinensis n. sp. (Spirurida; Camallanidae) from the intestines of Occidozyga laevis (Günther, 1858) (Anura; Dicroglossidae) is described and illustrated. Camallanus philippinensis n. sp. represents the 106th species assigned to the genus and the first from Philippine anurans. It is distinguished from other Oriental species by the pattern of caudal papillae (6 precloacal, 4 adcloacal, 8 postcloacal), length of spicule (323–329 µm), and postequatorial vulva. Occidozyga laevis is also found to harbor cyclophyllidean cysticerci. Occidozyga laevis represents a new host record for both of these helminths.

In northeastern Brazil, studies related to freshwater fish macroparasites are incipient. This paper presents 2 new records for cymothoid isopods plus a territory extension for a third species, all in Maranhão State, Northeast Brazil.

Herein, we present the first Mexican record of Morelet's crocodile, Crocodylus moreletii, as a host for the proboscis-bearing leech, Haementeria acuecueyetzin. From November 2004 to October 2017, we captured 111 crocodiles during spotlight surveys in lagoons of the Dziuché ejido, municipality of José María Morelos, Quintana Roo, Mexico. Twenty-one (18.9%) individuals had leeches identified as H. acuecueyetzin. It is the first report of H. acuecueyetzin for the State of Quintana Roo, Mexico, and the northernmost record of the species. This is also the second case of leech parasitism in C. moreletii. Haementeria acuecueyetzin likely parasitize a large array of vertebrates, and its role as a potential vector of blood parasites in C. moreletii requires further investigation.

Eight robust ctenotus individuals, Ctenotus robustus Storr, 1970, and 8 copper-tailed skinks, Ctenotus taeniolatus (White, 1790), from Australia were examined for helminths. Only Nematoda were found. Ctenotus robustus contained Skrjabinodon piankai. Ctenotus taeniolatus contained Abbreviata sp. (larvae in cysts) and S. piankai. Ctenotus robustus and C. taeniolatus are the fourth and fifth hosts to harbor S. piankai. All findings are new host records.

Natural infections of Paulisentis missouriensis (Acanthocephala), Rhabdochona canadensis (Nematoda), and Allocreadium lobatum (Trematoda) in the intestine of creek chub (Semotilus atromaculatus) were studied to determine whether microhabitat use of these helminths was affected by interspecific interactions. Comparison of mean relative positions and intestinal segment use of all 3 helminths revealed no negative interactions among the 3 species. Paulisentis missouriensis appeared entirely unaffected by the presence of either R. canadensis or A. lobatum. Each of the latter 2 species, however, appeared to exhibit some shift toward, rather than away from, the location of P. missouriensis in co-infected hosts. However, the effect size in both cases was small and therefore could be spurious. At higher intensities of co-infecting P. missouriensis, worms of A. lobatum were either distributed far to the anterior or far to the posterior of the intestinal locations occupied by P. missouriensis. This constituted the only evidence in the present investigation for negative interspecific interactions among these 3 frequently co-occurring helminths in this system.

Humans can become infected by Toxoplasma gondii oocysts released in the environment along with felid feces through the accidental ingestion of contaminated raw meat, water, fruits and vegetables, or through direct contact with contaminated soil. Documenting the extent of soil contamination by T. gondii oocysts is necessary to prevent infection caused by this protozoan. The aim of our study is to determine the occurrence of T. gondii oocysts in urban soil in Marrakesh, Morocco. A total of 42 soil samples were collected from 9 sites in the urban area of Marrakesh. Oocysts were extracted by the flotation method, and detected by microscopy using both bright-field and UV. The frequency and spatial distribution of T. gondii in soil were analyzed considering the factors that could affect the mode of contamination, such as the presence of cats and the survival conditions of oocysts. All analyzed soil samples from Marrakesh were negative. The results of the present study are correlated to the sensitivity of our detection method as well as the presence of cats, the main reservoir of this parasite. In addition, temperature, moisture, and soil composition can significantly influence oocysts survival, and consequently affect the probability of human contamination through food.

Three species of myobatrachid frogs from Borneo, Malaysia were examined for helminths: Leptobrachium abbotti (n = 5), Leptobrachium hendricksoni (n = 6) and Leptobrachium montanum (n = 12). Herein, we establish the initial helminth records for these 3 species. Found were 4 species of Nematoda: Cosmocerca ornata, Meteterakis sp., Oswaldocruzia sp., Cosmocercidae gen. sp. and 1 cestode gen. sp. Leptobrachium abbotti harbored C. ornata and Oswaldocruzia sp.; L. hendricksoni harbored Meteterakis sp. and Cosmocercidae gen. sp.; L. montanum harbored Oswaldocruzia sp. and 1 cestode gen. sp. Six new host records are reported.

This is the first report of nasopharyngeal myiasis by the larvae of Cephenemyia jellisoni infecting white-tailed deer (Odocoileus virginianus) from tropical dry forests in central Mexico. This study was conducted on hunted male deer within 2 wildlife management units located in the states of Puebla and Oaxaca. Bot fly larvae prevalence in both populations was 50% (95% CI: 21–78%, n = 12) with a median intensity of 4 (95% CI: 3–7). We recommend the implementation of a surveillance program at management units and the monitoring of female deer to determine differential gender effects.

We report zoonotic Spirometra erinaceieuropaei (Rudolphi, 1819) Faust, Campbell and Kellogg, 1929 (Diphyllobothriidae), from its natural ecosystem in Europe from Martes martes in Ukraine. Scanning electron microscopy (SEM) images revealed the presence of mineral concretions in the scolex area of S. erinaceieuropaei. The combination of SEM and metal analysis using a dispersive X-ray technique to study the body surface of the plerocercoid and calcareous body–like structures has never been performed before in cestodes. Gallium ion sectioning and metal analysis were performed to study mineral concretions in cestodes for the first time. The results revealed moderate levels of calcium, phosphorus, and magnesium in the scolex and tegument of plerocercoids. Calcareous body–like structures included high levels of calcium and moderate levels of magnesium on their surface.

Kissing bugs (Hemiptera: Reduviidae) are blood-feeding ectoparasites found primarily in the tropics and subtropics of the Americas. These bugs are vectors of Trypanosomatidae to their mammalian hosts, including humans. The distribution of Triatoma spp. in the Nearctic region is still not fully known, and their relevance as possible vectors of Trypanosoma cruzi to humans and animals is of growing concern. We report the first record of Triatoma sanguisuga from Wyoming, the northern-most reported collection in the western United States, and include collection records for Triatoma protracta in Colorado that were previously unclear.

A new nematode, Cosmocercoides minshan n. sp. (Cosmocercidae) is described from Bufo minshanicus in the Zoige grassland in southwestern China. The new species is characterized as a medium-sized worm (4.93–7.97 mm in length and 0.24–0.47 mm in width), but with a shorter spicule length (0.08–0.21 mm) than other Cosmocercoides, with lateral alae and 9 pairs of caudal papillae. Among the 21 recorded species in this genus, the morphology of the new species is different from all the other species previously reported. DNA sequences of C. minshan sp. showed that the species is almost identical to Cosmocercoides pulcher (99%), and Cosmocercoides tonkinensis (99%). However, there are differences in the morphology and structure of the rosetted papillae among these 3 species, as well as 4 nucleotide differences in the 18S–28S rDNA including the internal transcribed spacer region. In a neighbor-joining phylogenetic tree, C. tonkinensis, C. pulcher, and C. minshan formed a robust clade. Generally, the species is distinguished molecularly and morphologically; thus C. minshan is herein described as a new nematode species of Cosmocercoides.

Five Cape fur seals, Arctocephalus pusillus pusillus, 1 dusky kob, Argyrosomus coronus, and 55 silver kob, A. inodorus, collected from Cape Cross, Henties Bay, and Skeleton Coast Park, Namibia, were examined for acanthocephalans. Adults of Bolbosoma vasculosum and Corynosoma australe were recovered from 5 Cape fur seals, and cystacanths of C. australe from the single dusky kob and 3 of the silver kobs that were examined. This is the first record of B. vasculosum and the second of C. australe from the Namibian coast. Scanning electron microscopy of specimens of C. australe revealed features such as bursal papillae and micropores both on the proboscis hook surfaces and across the epidermal surface of the trunk. X-ray analyses of gallium cut hook, egg, and spines of C. australe are presented with analyses of spines of Corynosoma strumosum for comparison.