Fecal samples are often the only feasible means to assess diversity of parasites in wildlife; however, definitive identification of egg or larval stages in feces by morphology is rarely possible. We determined partial sequences from the second internal transcribed spacer region (ITS-2) of nuclear ribosomal DNA for first-stage, dorsal-spined larvae (DSL) in feces from caribou ( Rangifer tarandus tarandus (L., 1758), Rangifer tarandus caribou (Gmelin, 1788), Rangifer tarandus grantii (Allen, 1902)), muskoxen ( Ovibos moschatus moschatus (Zimmermann, 1780), Ovibos moschatus wardi Lydekker, 1900), moose ( Alces alces gigas Miller, 1899 and Alces alces andersoni Peterson, 1952), and from the tissue of one slug ( Deroceras laeve (Müller, 1774)) in Arctic–Subarctic North America. A previously uncharacterized, genetically distinct species was recognized based on sequences of 37 DSL from 19 ungulate hosts and the slug. Sequence similarity among individuals of this novel species was 91%–100%. For many individual DSL, paralogues of ITS-2 were detected. ITS-2 sequences from the novel species were 72%–77% similar to those of Varestrongylus alpenae (Dikmans, 1935) and 51%–61% similar to those of other protostrongylids known in North American and some Eurasian ungulates. Results indicate a discrete lineage of an undescribed protostrongylid infecting muskoxen, caribou, and moose from Alaska to Labrador. Sympatric infections with Parelaphostrongylus andersoni Prestwood, 1972 were found in three caribou herds.

Background: The genusMarshallagia(Family Haemonchidae, subfamily Ostertagiinae) contains multiple species of nematodes parasitising the abomasum (or duodenum) of ruminants, in particular of Caprinae. Male specimens have been described to be polymorphic with the frequent/major morphotype initially described in the genusMarshallagiawhile the minor/rare morphotype was initially often placed in the genusGrossospicularia. Due to common morphological features, certain pairs of morphotypes were suggested to belong to the same species such asMarshallagia marshalli/M. occidentalis. However, molecular evidence to confirm these pairs of morphotypes belonging to the same species is missing.Methods: In the present study,Marshallagiasp. were collected from domestic sheep in Uzbekistan. Male specimens were morphologically described with particular emphasis on the structure of the bursa copulatrix. After DNA isolation from morphologically identified specimens, PCRs targeting the ribosomal internal transcribed spacer 2 (ITS2) and mitochondrial cytochromecoxidase subunit 1 (cox1) regions were conducted. After Sanger sequencing, maximum likelihood phylogenetic analyses and pairwise identities between sequences were calculated.Results: The major morphotypes ofM. marshalli,M. schumakovitschiandM. uzbekistanicaand the minor morphotypesM. occidentalis,M. trifidaandM. sogdianawere identified and their morphology was documented in detail. ITS2 sequences showed little variation and did not allow diagnosing species. In contrast, phylogenetic analysis ofcox1 sequences identified highly supported clusters and verified thatM. marshalli,M. occidentalisandM. uzbekistanicaare different morphotypes of the speciesM. marshalliwhileM. schumakovitschiandM. trifidarepresent distinct morphotypes ofM. trifida. ForM. sogdianano corresponding major morphotype could be identified in the present study. Due to a large barcoding gap, comparison ofcox1 sequences in terms of percent identity was sufficient to reliably assign the sequences to a particular species without phylogenetic analysis.Conclusions: The data presented here create a framework that will allow the classification of other members of the genus in the future and underline that parallel morphological and molecular analysis of specimens is crucial to improve the taxonomy of polymorphic species.

Plant-parasitic nematodes are of great economic importance as widespread harmful plant pests of the world. Among them, root-knot nematodes, especially species of the genus Meloidogyne, cause significant damage to agriculture. In this paper the species composition, morphological and molecular genetic characteristics of root-knot nematodes in vegetable crops of the Zarafshan Valley of Uzbekistan were studied. As a result of morphological studies, three species belonging to the genus Meloidogyne were found in Samarkand region of the Zarafshan Valley; these species were Meloidogyne javanica, M. incognita and M. hapla identified by concentric lines in the anal-vulvar part of sexually mature female nematodes. The results show that the anal arch of M. javanica and M. hapla is low, and that of M. incognita is high. In order to additionally characterize the species of the discovered root-knot nematodes, we carried out their molecular identification. However, nucleotide sequence analysis in the 5S–ITS2 region of rDNA showed no differences between M. javanica and M. incognita, the overall difference being to 0.6%. These data indicate that both these taxa belong to the one species based on 5S–ITS2 region, but this datum should be supplemented by additional research with other genes. The sequence differences between the species M. javanica or M. incognita with species M. hapla amounted to 23%. Species analysis based on the analysis of morphological and molecular genetic indicators of root-knot nematodes is important because it was conducted for the first time in Central Asia. The studies conducted indicate that M. hapla, M. javanica and M. incognita are common on tomato farms in Payaryk, Akdarya and Jambay districts of Samarkand region of Uzbekistan.

The aim of the present study was to characterize the diversity of Metastrongylus spp. in wild boars and the earthworm intermediate host species contributing to the maintenance of the life cycle. Here, wild boars were subjected to parasitological necropsies, and lungworm species were identified morphologically, followed by confirmation using ITS-2 sequencing and a phylogenetic analysis. Earthworms were collected from wild boar habitats and investigated for the presence of larvae. The prevalence of Metastrongylus spp. in wild boars was 78.8%, and many individuals were positive for all three detected species, Metastrongylus pudendotectus, Metastrongylus salmi and Metastrongylus elongatus. The phylogenetic analysis did not clearly resolve all species, except for M. pudendotectus. Age group and season had no influence on prevalence, while intensity was significantly higher in autumn than in spring and summer (Kruskal–Wallis followed by Dunn’s test). Three out of six investigated earthworm species were positive for metastrongyloid larvae (prevalence of 10.4–16.7%), but neither their phylogenetic relationship nor ecological microhabitats were able to explain these differences. Further sequence data should be used to improve the resolution in phylogenetic trees to determine potential cryptic species in the genus, while the application of deep sequencing approaches might provide insights into species-specific epidemiology and pathology.

Morphological analysis of lungworms collected among Caprinae from Uzbekistan resulted in the identification of four species of Protostrongylidae: Protostrongylus rufescens, Protostrongylus hobmaieri, Spiculocaulus leuckarti and Cystocaulus ocreatus. The following species were recorded as definitive hosts: Ovis aries, Ovis ammon, Ovis vignei, Capra hircus, Capra falconeri and Capra sibirica. The prevalence of P. rufescens reached 45.3%, followed by S. leuckarti and C. ocreatus with 31.7% and P. hobmaieri with 16.9%. The sex ratio ranged between 1:3.1 and 1:6.2, with P. hobmaieri showing the strongest predominance of females over males. The prevalence of infection of small ruminants with protostrongylid nematodes increased with the age of the hosts. Protostrongyles use terrestrial gastropods as intermediate hosts, and infective larvae were found in the species Vallonia costata, Gibbulinopsis signata, Pupilla muscorum, Pseudonapaeus albiplicata, Pseudonapaeus sogdiana, Leucozonella ferghanica, Xeropicta candacharica, Candaharia levanderi and Macrochlamys sogdiana. Xeropicta candacharica was the most abundant gastropod and had the highest prevalence of infection with protostrongylids. Adult X. candacharica had a significantly higher infection intensity than juveniles. The epidemiology of protostrongylid infections is dynamic and subject to considerable changes. Further characterization of the interaction of protostrongylid parasites with their terrestrial gastropods as intermediate hosts and Caprinae as definitive hosts is required to understand these processes and to monitor the effects of changing ecological contexts.