Trematodes of the subclass Digenea are a major impediment to catfish aquaculture in the southeastern United States. Catfish production ponds are ideal feeding grounds for piscivorous birds, and given the variety of aquatic snails that inhabit these ponds, they offer a prime environment for the propagation of digenetic life cycles. In July 2014, snails morphologically consistent with Biomphalaria havanensis L. Pfeiffer, 1839, were collected from 2 different catfish production ponds in the catfish farming region of eastern Mississippi. These snails were refractory to Schistosoma mansoni Sambon, 1907, infection, and phylogenetic analyses based on internal transcribed spacer (ITS)1 and ITS2 fragments placed the snails within the B. havanensis/obstructa complex. Some (1.5%) of these snails shed cercariae morphologically and molecularly consistent with Drepanocephalus auritus Kudlai, Kostadinova, Pulis, and Tkach, 2015 (formerly reported as Drepanocephalus spathans Dietz, 1909), an echinostomatid parasite of the double-crested cormorant Phalacrocorax auritus Lesson, 1831, and channel catfish Ictalurus punctatus Rafinesque, 1818. Juvenile channel catfish were challenged individually with ∼275 cercariae of D. auritus per fish, resulting in limited mortality (2 out of 10 fish). Surviving fish were euthanatized 7 d postchallenge, and the presence of metacercariae was confirmed histologically. Parasite-associated pathology was consistent with previous studies. Subsequent molecular analysis of 5 different gene targets confirmed morphological identifications. Previous research has suggested the existence of discrete North American and South American haplotypes of D. auritus. Mitochondrial cytochrome c oxidase subunit 1 and nicotinamide adenine dinucleotide dehydrogenase subunit 1 sequences demonstrated that both haplotypes were released by snails in this study, suggesting a broader distribution of these genetic variants than previously thought. Along with Planorbella trivolvis Say, 1817, this work identifies a second snail species common to catfish aquaculture ponds that releases D. auritus infective to juvenile channel catfish and is the first report of B. havanensis as an intermediate host for D. auritus in North America.

A total of 100 American coots, Fulica americana Gmelin, 1789, were examined for metazoan parasites from the Chihuahua Desert, Middle Rio Grande Valley Texas, and from the Upper Rio Grande Valley, Colorado, U.S.A., between 1984 and 1986. There was no significant difference in helminth species richness or median abundance between the component communities from the 2 localities. Fifteen of the 25 helminth species collected were in common to both, and similarity was 65%. The same species in each of the 4 taxa, Notocotylus pacifera, Diorchis americana, Amidostomum fulicae, and Polymorphus spp., had the highest prevalence and abundance in both, and the same 5 species of acanthocephalans were also in common. Eight of the 9 species of ectoparasites were common, and similarity was 91%. In both host species, Pseudomenopon pilosum and Rallicola advenus were the most prevalent and abundant mallophagans, and Laemobothrian atrum was the least. The nasal mite Rallynyssus caudistigmus was present in hosts from both localities. Of the 3 unidentified species of feather mites, species 1 was the most prevalent and abundant in Texas and absent in hosts from Colorado, and species 3 was the most prevalent in hosts from Colorado. The following helminth species were present in all 3 seasonal samples in Texas: A. fulicae, D. americana, Diorchis ransomi, N. pacifera, Polymorphus trochus, and Tetrameres globosa, whereas D. americana had the highest mean intensity in all 3. Overall, 70 species of helminths (33 trematodes, 15 cestodes, 14 nematodes, and 8 acanthocephalans) have been recorded in F. americana from North America. All species, except Echinostoma americanum, have been reported from other species of hosts. The majority of species are generalists (90%), although the following are specialists and largely predictable in American coots: trematodes (N. pacifera and Cyclocoelum mutabile); cestodes (D. americana, and D. ransomi); nematodes (A. fulicae, in adult coots only); Pelecitus fulicaeatrae; and the acanthocephalan, P. trochus.

We herein redescribe Allobenedenia dischizosepta (Suriano, 1975) n. comb. (Monogenoidea: Capsalidae) based on light microscopic analysis of the holotype and 18 paratypes from the gill of Acanthistius brasilianus (Cuvier, 1828) (Perciformes: Serranidae) along with light and scanning electron microscopy of 25 newly collected specimens from the gill of Acanthistius patachonicus (Jenyns, 1842) (new host record) in the southwestern Atlantic Ocean off Argentina. Contradicting the original description of this species and its generic diagnosis, all specimens had 5 loculi (2 anterior plus 3 posterior loculi) plus 5 corresponding haptoral septa only (central loculus absent). The original description of this species erroneously specified 6 loculi, including 2 small anterolateral loculi. Because A. dischizosepta was the type species for Tetrasepta Suriano, 1975 and because it fits the diagnosis of Allobenedenia Yamaguti, 1963, the genus therefore is regarded a junior synonym of Allobenedenia. Allobenedenia dischizosepta differs from its congeners by lacking a haptoral peduncle as well as by having 5 haptoral loculi, accessory sclerites that lack a conspicuous dorsal protuberance and that are weakly bifid, by posssesing robust anterior hamuli that are strongly recurved for half of their total length, by having a male accessory gland reservoir in the extreme posterior portion of the penis sac and lateral to the vitelline reservoir abutting the ovary, and by the presence of a straight (not coiled) proximal portion of the ejaculatory duct within the penis sac.

The present study describes a new species of Cosmetocleithrum Kritsky, Thatcher and Boeger, 1986 from the gills of the catfish Trachelyopterus galeatus (Linnaeus, 1766) from the mouth of the Aguapeí River, municipality of Castilho, São Paulo State, Brazil. Cosmetocleithrum laciniatum n. sp. closely resembles Cosmetocleithrum striatuli Abdallah, Azevedo and Luque, 2012 and Cosmetocleithrum longivaginatum Suriano and Incorvaia, 1995 by the shape of dorsal and ventral bars (straight with enlarged ends), and Cosmetocleithrum gussevi Kritsky, Thatcher and Boeger, 1986 by having a Y-shaped accessory piece. The new species can be distinguished from most of its congeners by having a coiled cirrus with a 1½ counterclockwise ring with a sclerotized base possessing lateral flaps. This species is the second found to contain members of Cosmetocleithrum parasitizing the gills of Auchenipteridae. A note on the morphology of C. striatuli, a parasite of Trachelyopterus striatulus, is also presented.

From 1999 through 2012, a total of 541 individual rodents (jerboas of the family Dipodidae) were collected from several habitat types, primarily from the Gobi region of Mongolia, and were examined for helminth and protistan parasites. Of those rodents, 25 were identified as Pygeretmus pumilio Kerr, 1792 (Rodentia: Dipodidae), whereas 516 were other species of jerboa from the provinces of Dornogobi, Dundgobi, Omnogobi, Ovorhangai, Bayanhongor, Gobi Altai, and Hovd. During our field work, we collected several cestodes; some of which represented undescribed species, and these new species occurred in 40% of P. pumilio from four separate collecting localities. We designate this new species as Catenotaenia tuyae n. sp. (Cyclophyllidea: Catenotaeniidae), which is characterized by having relatively long and narrow gravid proglottids and an ovary in mature segments that is located antiporally in the anterior portion of the mature proglottids. In addition, the position and the ratio of the genital pore toward the anterior end of the proglottids are unique and the ovary is elongate, being confined to the antiporal part of the mature proglottid. These morphological features serve to differentiate Catenotaenia tuyae from all other species in the genus included in the phylogenetic analysis and are supported by molecular phylogenetic evidence using the 28S ribosomal RNA gene. The intensity of C. tuyae infection in Pygeretmus ranged from 1 to 3 individual cestodes per infected host.

Several species of western North American chipmunks (Rodentia: Tamias) are distributed in overlapping ranges. Field-collected specimens of 9 species of chipmunks from 8 U.S. states were examined externally for fleas (Siphonaptera). We document flea infestations and 1 new range extension. This work demonstrates that ongoing field collection can shed light on host and parasite distributions over large geographical areas.

Fifty-six plateau brown frogs, Rana kukunoris Nikolsky, 1918, were collected from June to August 2014, and examined for parasites. Our goal was to survey the parasite species and its prevalence and mean intensity from the plateau brown frog in the Northeast of Qing-Tibetan plateau. Thirty-three of 56 (59%) frogs examined were infected with 1 or more parasites, including 19 (34%) with Dolichosaccus ranae Wang, 1980; 11 (20%) with Nematotaenia dispar (Goeze 1782) Lühe, 1899; 53 (95%) with Aplentana leesi Hristovski and Riggo, 1975; 3 (5%) with Rhabdias sp.; and 8 (14%) with unidentified juvenile nematodes. In addition, 4 (7%) frogs were found to harbor a previously unreported isosporan, which we describe herein. Sporulated oocysts of the new isosporan were ellipsoidal, 14.2 × 10.2 (12–16 × 8–12)  μm, with a smooth, thin wall, and a shape index of 1.4 (1.1–1.8). No micropyle or oocyst residuum were present, but the oocysts contained one polar granule composed of 1–2 globules stuck together. Sporocysts were ovoidal, 8.7 × 7.2 (8–10 × 6–9) μm, with a shape index of 1.2 (1.0–1.4), and lacked Stieda, sub-Stieda, and para-Stieda bodies; they possessed a large sporocyst residuum consisting of an aggregate of granules bounded by a limiting membrane. Sporozoites were sausage-shaped, with one end slightly pointed and arranged head-to-tail around the sporocyst residuum; refractile bodies and nuclei were not discernible. These parasite species were recovered from R. kukunoris in China and all represent new host and distribution records.

Meteterakis hurawensis n. sp. (Nematoda, Heterakidae) from the large intestine of Brachymeles orientalis and Brachymeles samad (Squamata, Scincidae) is described and illustrated. Meteterakis hurawensis n. sp. represents the 20th Oriental species assigned to the genus and is distinguished from other Oriental species by the distribution pattern of the caudal papillae (10 pairs total, 3 pairs of relatively large pedunculate papillae, 2 pairs of short pedunculate papillae immediately anteriolateral to ventral sucker, 2 pairs of short pedunculaltle papillae midway between ventral sucker and cloaca, 1 pair of sessile papillae just posterior to cloaca, 2 pairs of sessile near terminus of tail; 1 unpaired sessile papilla on midline just anterior to cloaca) and length of spicules (0.30–0.33 mm).

Caecincola septimus n. sp. is described from the intestine of largemouth bass (Micropterus salmoides) collected from Turkey Creek and Menard Creek in the Big Thicket National Preserve, Texas, U.S.A. Members of the new species are most easily distinguished from Caecincola longiscens and Caecincola cookorum by having ceca that do not extend past the anterior testis or into the posttesticular space, and from the remaining species in the genus (Caecincola autumnae, Caecincola latostoma, Caecincola parvulus, and Caecincola wakullata) by a combination of body size and shape, arrangement of the testes, number of ovarian lobes, and size of the oral sucker. This is the fourth species of Caecincola described from largemouth bass, the others being C. parvulus from Wisconsin, C. wakullata from Florida, and C. latostoma from Louisiana.

Single juvenile specimens of a species of Centrorhynchus were collected from the small intestines of 3 stray dogs in Qom, Qom Province, Iran, constituting the third report of a centrorhynchids from a dog. The proboscis morphology and armature, 24–28 longitudinal rows of 9–10 hooks, were most similar to juveniles of Centrorhynchus mysentri from the Indian bullfrog, Hoplobatrachus tigerinus, and adults of Centrorhynchus globirostris from the pheasant crow Centropus sinensis, which are described from India and Pakistan, respectively. The dogs may have become infected when eating infected frogs.

We report herein a nymphal Amblyomma dissimile Koch, 1844 (Acari: Ixodidae) parasitizing an adult Rhinella margaritifera (Anura: Bufonidae) in lowland tropical rainforest in French Guiana. This is the first report of a tick parasitizing R. margaritifera.

Confusion regarding the identification of Placobdella hollensis (Whitman, 1892) (Hirudinida: Glossiphoniidae) has led to an unclear understanding of the distribution of the species. Two specimens of P. hollensis were collected from Merchants Millpond State Park, Gates County, North Carolina, U.S.A., representing a new geographic distribution record. Specimens were confirmed as P. hollensis by morphological and molecular study. Specimens of P. hollensis from North Carolina, had accessory eyes, 2 thin paramedial dark lines, and 3 pairs of pre-anal papillae. Molecular comparison of cytochrome c oxidase subunit I sequence data revealed a 99.0 to 99.7% similarity to specimens of P. hollensis collected from its type locality (Barnstable County, Massachusetts, U.S.A.). From confirmed specimens of P. hollensis, this report supports the assertion that P. hollensis has an Atlantic coastal distribution.

The objective of this study was to assess seasonal changes in the maturation of adult Cotylaspis insignis recovered from the gill and visceral mass junction of the fat mucket, Lampsilis radiata luteola, over 14 months. Mussels were collected from North Elkhorn Creek, Scott County, Kentucky, U.S.A., between May 2015 and July 2016. Staging of C. insignis (N = 675 worms) was based on the following criteria: Stage 1 = 17–18 peripheral alveoli in ventral sucker and 8 medial alveoli; Stage 2 = 19–20 peripheral alveoli in ventral sucker and 9 medial alveoli; Stage 3 = developing vitellaria present; Stage 4 = eggs present. Seasonal changes in the proportions of these stages were apparent in this study. Recruitment of a new cohort of adult worms by mussels began by December, as evidenced by an increasing proportion of Stage 2 worms; this increase coincided with a steady decrease in Stage 4 worms between November and March. By March and April, developing vitellaria (i.e., Stage 3 worms) became obvious in many C. insignis, and the majority of worms in this new cohort began to engage in egg production (Stage 4 worms) between late May and early June.

Neobenedenia pacifica (Monogenoidea: Capsalidae) is redescribed from the skin and eye of the striped mullet Mugil cephalus and white mullet Mugil curema from localities off Florida and Mississippi. The capsalid is confirmed as a member of Neobenedenia, and its occurrences off Florida and Mississippi represent new distribution records for the species.

A large collection of caryophyllaeid tapeworms from catostomid fishes in eastern Texas, U.S.A. was utilized to evaluate the reliability of key morphological features that putatively distinguish between Glaridacris confusus and Glaridacris laruei. The number of testes, anterior extent of the testicular and vitelline fields, shape of the postovarian vitelline follicles, spatial relationship between the postovarian vitelline follicles and the ovary, postgonopore distance, and dimensions of the testes were all examined to determine if they correlated, as suggested in published dichotomous keys. No character was unambiguously associated with the overall morphotype of either species, and features supposedly diagnostic of one species were associated with features supposedly diagnostic of the other. The high variability among these character associations observed in the present investigation, combined with the variability reported by past investigations, suggests that new collections will be needed to clarify the species-level diversity in Glaridacris.

Twenty-eight representatives of the scincid lizard Lobulia brongersmai from Papua New Guinea were examined for gastrointestinal helminths. One species of Digenea, Saurokoilophilia kinsellai, and two species of Nematoda, Parapharyngodon maplestoni and Skrjabinodon sheai, were found. Skrjabinodon sheai had the highest prevalence (18%) and the greatest number of helminths (n = 15), range = 1–6. Lobulia brongersmai is infected by generalist helminths that have been reported from other species. Three new host records are reported.

We collected 2 species of Monogenoidea from the gills of 9 of 29 (31%) Rainbow Darters (Etheostoma caeruleum) from Arkansas. We found Gyrodactylus etheostomae on 4 of 29 (14%) from 3 localities and Aethycteron caerulei on 7 of 29 (24%) from 4 localities. These are the first records for A. caerulei from Arkansas and the first for parasites from E. caeruleum west of the Mississippi River. Based on geographic distribution and morphological similarity, we suggest amending the following previously reported host records for G. etheostomae as follows: Etheostoma asprigene to Etheostoma exile in North Dakota and Etheostoma radiosum tentatively to Etheostoma uniporum in Arkansas.

During August 2016 we sampled fish from Vicente Guerrero Reservoir (also known as Las Adjuntas Reservoir), Tamaulipas, Mexico to increase the inventory of endohelminths parasitizing 3 species of fish inhabiting this water body and to identify their possible zoonotic potential. We collected 2 introduced species of fish, Cyprinus carpio (n = 10) and Oreochromis aureus (n = 15), and 1 native species, Micropterus salmoides (n = 17). The 2 introduced species were examined for parasites for the first time from this reservoir. As result, we found 4 species of parasite: 2 larvae of nematodes (Contracaecum sp. and Spiroxys sp.) and 2 trematodes (Posthodiplostomum minimum in the larval stage and adults of Saccocoelioides sp.), but none with zoonotic potential. Only nematodes parasitized 2 species of fish, but their prevalence and mean intensities were not significantly different between the host species. This work is the first parasitological study of O. aureus in Tamaulipas, and the records of the trematodes and Spiroxys sp. in Vicente Guerrero Reservoir represent new locality records.

Forty threatened and endangered Malaysian freshwater turtles representing four species in four genera of Geoemydidae (Cuora amboinensis, Heosemys grandis, Orlitia borneensis, Siebenrockiella crassicollis) destined for the Chinese food market were seized by authorities in Hong Kong in 2001 and transferred to the University of Florida, Gainesville, Florida, U.S.A. to be examined for metazoan parasites. The parasites of these turtles were removed, preserved, and tentatively identified. Specimens collected were subsequently transferred to the Laboratory of Parasitology, Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, Texas, U.S.A. for further examination. Fourteen species of endohelminths (9 nematodes, 5 trematodes) and 1 leech were recovered. Thirteen new host records (Orientodiscus linguiformes from C. amboinensis; Meteterakis striatura, Proatractis sp., Trichoskrjabinia malayana, O. linguiformes, and Parapleurogonius brevicecum from H. grandis; Orientatractis sp., Telorchis clemmydis, and Orientodiscus fernandoi from Orlitia borneensis; Orientodiscus buckleyi, O. linguiformes, T. clemmydis, and Placobdelloides stellapapillosa from S. crassicollis) are reported, and expanded variability in T. clemmydis from 4 individual turtles is recorded. This project offered a rare opportunity to record parasites from threatened and endangered species.