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At least 163 records · Page 9Linked to original sources

Parasites of the slimy sculpin, Cottus cognatus Richardson, 1836, from Lake Huron, U.S.A

One hundred slimy sculpins, Cottus cognatus (Cottidae), collected from Six Fathom Bank Lake Trout Refuge in Lake Huron in June 1995 were examined for parasites. A total of 17 parasite species (3 Digenea, 2 Monogenea, 3 Cestoda, 3 Nematoda, 2 Acanthocephala, 2 Ciliophora, 1 Microspora, and 1 Myxosporea) were found to infect sculpins. Tetracotyle sp. had the highest prevalence, mean intensity, and mean abundance, followed by Diplostomum sp. The most common gastrointestinal helminth species was Echinorhynchus salmonis . Epistylis sp. occurred on the gills of 79 sculpins. The mean parasite species richness ± SD and mean helminth abundance ± SD were 5.4 ± 1.6 and 242.6 ± 264.5, respectively. The mean Brillouin's diversity and evenness values were 0.5773 ± 0.1915 and 0.5248 ± 0.1892, respectively. Although the helminth community of slimy sculpins is dominated by larval trematodes that mature in piscivorous birds, it is believed that few slimy sculpins are eaten by birds at this location.

Comparative Parasitology

Distribution of Placobdella hollensis (Whitman, 1892) (Hirudinida: Glossiphoniidae)

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.

Comparative Parasitology

Intestinal helminths in mourning doves (Zenaida macroura) from Arizona, Pennsylvania, South Carolina, and Tennessee, U.S.A.

We examined 115 hunter-killed mourning doves ( Zenaida macroura ) from 4 states (Arizona, Pennsylvania, South Carolina, and Tennessee, U.S.A.) in 1998 and 1999 to investigate geographical variation in the prevalence and intensity of intestinal helminth infections. Four intestinal helminth species were identified: Killigrewia delafondi , Ornithostrongylus crami , Ascaridia columbae , and Capillaria obsignata . The number of worms (all helminth species combined) per infected bird ranged from 1 to 166 (mean ± SE = 12.7 ± 7.45, median = 2.0). Filarids, Aproctella stoddardi , were found in 2 birds but were probably adhering to the outside of the intestine. Overall, 18% of the doves were infected with 1 or more species of helminths. The percentage of doves infected with at least 1 helminth species varied from 4% in Arizona to 27% in South Carolina. Mixed infections occurred in only 3 individuals (14% of infected birds). We found no significant differences in prevalence of infection among any of the 4 helminths by host age or sex, and prevalences were too low to test for differences among states. The intensity of O. crami was higher in males than in females but did not differ significantly among states. Intensities of the other 3 helminths did not differ by sex or state, and we found no differences in helminth intensity by age. Intestinal length was significantly greater in infected than in uninfected birds.

Arizona, Pennsylvania, South Carolina, Tennessee

Parasites of the African clawed frog, Xenopus laevis , in southern California, U.S.A

A total of 230 feral African clawed frogs, Xenopus laevis , from 3 localities in southern California were examined for parasites. The following species were found: 3 species of Protozoa, Nyctotherus sp., Balantidium xenopodis , Protoopalina xenopodus ; 2 species of Monogenea, Protopolystoma xenopodis , Gyrdicotylus gallieni ; 1 species of Digenea, Clinostomum sp. (as metacercariae); 1 species of Cestoda, Cephalochlamys namaquensis ; 2 species of Nematoda, Contracaecum sp. (as larvae), Eustrongylides sp. (as larvae); and 1 species of Acanthocephala, Acanthocephalus sp. (as cystacanth). Of these, the protozoans P. xenopodus and B. xenopodis , both monogeneans, and the cestode have an African origin. Contracaecum sp., Eustrongylides sp., and Acanthocephalus sp. have not been previously reported from X. laevis .

Comparative Parasitology

Parasites of the mink frog (Rana septentrionalis) from Minnesota, U.S.A.

Twenty-two mink frogs, Rana septentrionalis , collected from two locations in Minnesota, United States, were examined for helminth and protozoan blood parasites in July 1999. A total of 16 parasite taxa were recovered including 5 larval digenean trematodes, 7 adult digenean trematodes, 3 nematodes, and 1 Trypanosoma species. Infracommunities were dominated by the digeneans in terms of richness and abundance. In particular, echinostomatid metacercariae in the kidneys of frogs were the most common parasites found, infecting 100% of the frogs and consisting of about 90% of all helminth individuals recovered. Gorgodera amplicava , Gorgoderina multilobata , Haematoloechus parviplexus , Haematoloechus breviplexus , Cosmocercoides dukae , and Oswaldocruzia pipiens represent new host records. The survey presented here represents the second known helminth survey of mink frogs conducted in North America. A summary of metazoan parasites reported from mink frogs is included.

Minnesota

Parasite distribution, prevalence, and assemblages of the grass shrimp, Palaemonetes pugio, in Southwestern Alabama, U.S.A.

The grass shrimp, Palaemonetes pugio , harbors a number of symbionts within its North American range. Here, we document the distribution and seasonality of 4 taxonomic groups that use P. pugio as a host in coastal Alabama. We conducted a regional survey of 4 symbionts of P. pugio over 3 seasons and compared assemblages across space and time. The most common parasite was the metacercarial stage of the microphallid trematode Microphallus turgidus , which remained consistently prevalent over the 3 seasons surveyed. We also monitored the prevalence of M. turgidus at 2 sites monthly. Prevalence fluctuated significantly among seasons at these sites, but spatial heterogeneity appears to have a stronger influence on regional parasite prevalence. Distributions of 3 of 4 symbionts overlapped in a single geographic area (Mon Louis Island, Alabama, U.S.A.); however, multispecies infections of individual hosts were normally distributed within host populations. Sites surrounding Mon Louis Island had substantially higher parasite prevalence, particularly in the summer months. This area had a high quantity of Spartina marsh habitat, which we found influenced parasite prevalence, suggesting a role for wetland habitat in structuring parasite communities for this host.

Alabama

Acanthocephalan parasites of slimy sculpin, Cottus cognatus , and Ninespine Stickleback, Pungitius pungitius , from Lake Michigan, U.S.A.

In total, 288 slimy sculpins, Cottus cognatus , were collected in September 2003 from 6 Lake Michigan, U.S.A., ports, along with 220 ninespine sticklebacks, Pungitius pungitius , from 3 ports. The ports included Waukegan, Illinois; Port Washington (PW) and Sturgeon Bay (SB), Wisconsin; and Manistique (MS), Frankfort (FF), Ludington (LD), and Saugatuck, Michigan. Echinorhynchus salmonis infected sculpins from 6 ports, Acanthocephalus dirus infected sculpins from 4 ports, and Neoechinorhynchus pungitius infected sculpins from 3 ports. Echinorhynchus salmonis infected significantly more sculpins at PW and at FF than at MS and LD. There were several significant differences in the intensities and abundances of E. salmonis among ports. Acanthocephalus dirus significantly infected more sculpins and had significantly higher abundances at FF than at PW, MS, and LD. Echinorhynchus salmonis , A. dirus , and N. pungitius infected sticklebacks from SB, MS, and FF. Neoechinorhynchus pungitius significantly infected more sculpins and more sticklebacks, and it had significantly higher abundances at MS than at FF. Neoechinorhynchus pungitius was the most common acanthocephalan in C. cognatus and P. pungitius at MS. These acanthocephalan species infecting C. cognatus and P. pungitius corresponded in their occurrence to those organisms that serve as their intermediate hosts found in the stomachs of both fish species. Potential changes in the diet of C. cognatus played a role in significant differences found for E. salmonis and N. pungitius at MS. One of these acanthocephalan species was always the most numerous helminth species found in the digestive tracts of P. pungitius and C. cognatus from these Lake Michigan ports.

Illinois;Wisconsin;Michigan

Parasites of Bloater Coregonus hoyi (Salmonidae) from Lake Michigan, U.S.A

In total, 158 bloaters Coregonus hoyi collected in September and October 2011 from 4 Lake Michigan, U.S.A., ports were examined for parasites. The ports included Waukegan (WK), Illinois; Port Washington (PW) and Sturgeon Bay (SB), Wisconsin; and Saugatuck (SG), Michigan. Parasites found in bloaters by port were cestodes Cyathocephalus truncatus (WK, PW, and SB) and Eubothrium salvelini (WK, PW, SB, and SG); the nematode Cystidicola farionis (WK, PW, SB, and SG); acanthocephalans Acanthocephalus dirus (WK and PW), Echinorhynchus salmonis (WK, PW, and SB), and Neoechinorhynchus tumidus (SB); and the copepod Salmincola corpulentus (WK and PW). Gravid individuals of all parasite species were found except for E. salvelini and A. dirus. Cystidicola farionis had the highest prevalence at each port, and the highest mean intensity and mean abundance at PW. The numbers of C. farionis at PW were significantly higher than those at WK and SB. Echinorhynchus salvelini had the highest mean intensities and mean abundances at WK, SB, and SG. The values for parasite species richness in bloaters were similar among ports. The total numbers of parasites were similar between WK and PW, but they were higher at these ports than at SB. The parasite faunas of bloaters were characterized by autogenic helminth species.

Comparative Parasitology

New host and distributional records for Cryptosporidium sp. (Apicomplexa: Cryptosporidiidae) from lizards (Sauria: Gekkonidae, Scincidae) from the Cook Islands and Vanuatu, South Pacific

Between 1991 and 1993, 295 lizards, comprising 21 species in 2 families (Gekkonidae, Scincidae) from the Cook Islands, Fiji, Palau, Takapoto, and Vanuatu in the South Pacific, were examined for Cryptosporidium oocysts. Only 6 lizards (2%) were found to be passing Cryptosporidium oocysts in their feces, including 2 of 30 (7%) Oceania geckos, Gehyra oceanica , from Rarotonga, Cook Islands, and 4 of 26 (15%) Pacific blue-tailed skinks, Emoia caeruleocauda , from Efate Island, Vanuatu. This represents the largest survey for Cryptosporidium in Pacific island lizards, and we document 2 new host and 2 new locality records for this parasite genus.

Comparative Parasitology

New host and distribution records of the leech Placobdella sophieae Oceguera-Figueroa et al., 2010 (Hirudinida: Glossiphoniidae)

Placobdella sophieae Oceguera-Figueroa et al., 2010 (Hirudinida: Glossiphoniidae) is reported from Oregon, California, and British Columbia for the first time. New hosts reported for P. sophieae include Taricha granulosa (rough-skinned newt), Rana pretiosa (Oregon spotted frog), and Anaxyrus boreas (western toad). Placobdella sophieae exhibits relatively low host specificity and all amphibians occurring in the Pacific Northwest are potential hosts.

Comparative Parasitology

Eimeria albigulae (Apicomplexa: Eimeriidae): New host and distributional record from the Bryant's woodrat, Neotoma bryanti (Rodentia: Cricetidae), from California, U.S.A.

Fecal samples, collected in July 2020 and April–May 2021 from 17 Bryant's woodrats, Neotoma bryanti Merriam, from 3 sites in San Diego, Orange, and San Bernardino counties, California, were examined for coccidial parasites. Three of 8 (38%) woodrats from a single site in San Diego County were found to be passing oocysts of Eimeria albigulae Levine, Ivens, and Kruidenier, 1957. Subspheroidal oocysts measured (average length [L] × width [W]) 23.5 × 21.4 µm with an average L/W ratio of 1.1. A micropyle was absent, but an oocyst residuum as well as a single polar granule was present. Ovoidal sporocysts measured (average L × W) 10.1 × 7.5 µm with an L/W ratio average of 1.4. A nipple-like Stieda body was present, but sub-Stieda and para-Stieda bodies were absent. The sporocyst residuum was composed of loosely packed granules between and around the sporozoites. This woodrat represents the sixth host to harbor this coccidian. We document a new host as well as a geographic distribution record for E. albigulae .

California

Blood parasites of birds of the District of Columbia and Patuxent Research Refuge vicinity

Recently a number of surveys of blood parasites of birds have been made in different parts of this country by different workers, the general purpose of which was to further the knowledge of the distribution and pathogenicity of these protozoa. This paper treats the distribution of parasites found in sampling miscellaneous birds of the District of Columbia and vicinity and contains a preliminary report on the more important phase of the problem of pathogenicity.

Maryland