Four species of adult cestodes and one larval form were recovered from Rattus assimilis (Gould, 1858) from Queensland. Hymenolepis diminuta Rudolphi, 1819; and the cysticercus of Taenia taeniae-formis (Batsch, 1786) are new host records for Australia; the same infestations with Raillietina (Raillietina) celebensis (Janicki, 1902) have also been recorded by Baer and Sandars (1956). Two new species, viz:—Choanotaenia ratticola and Hymenolepis australiensis are described.

The type specimens are lodged in the Queensland Museum, Brisbane. Cotype and other specimens studied are also lodged in the Queensland Museum and in the Institut de Zoologie, Université de Neuchâtel, Switzerland; the Department of Parasitology, London School of Hygiene and Tropical Medicine and in the British Museum (Natural History).

5-Hydroxytryptamine (5-HT) (1, 2 and 5 mM) significantly stimulated the incorporation of radioactive inorganic phosphate (32Pi) into phosphatidylinositol, phosphatidyiethanolamine, phosphatidic acid and also total phospholipid fraction of Hymenolepis diminuta after one hour of incubation. Such effect was both time and concentration dependent. In the presence of 5-HT early labelling of phosphatidylinositol was observed. Also, the percentage stimulation by 5-HT was the highest in this fraction under all experimental conditions. The inorganic, organic, total and phosphatidylcholine-bound phosphate of H. diminuta incubated with 5-HT were not significantly different from those of the control under all incubation conditions. Results reported herein suggest that messenger molecules that are derived from phosphoinositides may be involved in the stimulatory mechanism of 5-HT in H. diminuta.

Collyricloides massanae (Trematoda: Collyriclidae) is described from cysts in the wall of the small intestine of a starling (Sturnus vulgaris L.) in the Netherlands. The original description was from a yellow necked mouse, Apodemus flavicollis (Melchior), so this is the first record of this species in birds.

While investigating Red Ring Disease of coconuts, the authors detected Rhadinaphelenchus cocophilus (Cobb, 1919) Goodey, 1960 in the root systems of three otherwise healthy coconut trees. One of these was about seven years old; the roots and the stem were sampled five times weekly but no stem or petiole infection was detected. A similar state of affairs was detected in the second tree. In neither case over a period of several weeks was there evidence of upward movement of the worm into the stem. The third tree was more interesting: the first sampling disclosed the presence of the nematodes in only one sample of roots out of four taken equidistantly around the stem; subsequent examination showed that the infection spread through the root system in the neighbourhood of the base of the tree until at the end of one month, worms were recovered from all parts of the proximal root system and the population had increased to 100–150 worms per gm. of root: many of these were sexually mature; after a further two weeks, there was still no upward movement into the stem.

Allocreadium sudanensis sp. nov. is described from a cyprinid fish (Barbus bynni) from the White Nile in the Sudan. The new species is compared with other related species of Allocreadium.

A key for identification of five African species of the genus Allocreadium is given.

The present material was collected by the senior author in January, 1969 from the intestine of a cyprinid fish, Barbus bynni (Forskal), caught from the White Nile at Rabag near Kosti (about 200 miles to the south of Khartoum) in the Sudan. Eighteen trematodes, collected from a single infected fish, were fixed in hot 70% alcohol. Examination of these specimens in whole mounts stained in aceto-alum carmine and in sectioned material revealed that they belong to a hitherto unknown species of trematodes belonging to the genus Allocreadium, Looss (1900) which is described here as Allocreadium sudanensis sp.

Bilharziasis is unquestionably one of the major parasitic diseases of Southern Africa where both the urinary and intestinal forms occur. When it presents in the classical form, the diagnosis either from the clinical or laboratory viewpoint is seldom a major problem; but when, as so often happens, the presenting features have little in common with the accepted text-book descriptions of the disease, diagnosis becomes a matter of considerable difficulty.

The nematode Nothacrobeles lanceolatus was described in arid soils from Cabo de Gata-Níjar Natural Park, province of Almería (Spain). Since then this species has not been found again. In this study, new data on the distribution and morphological, morphometrical and molecular characteristics (based on 18S and 28S ribosomal DNA) of N. lanceolatus is provided. This species is characterized by having a tessellated cuticle, with its inner layer bearing two rows of cuticular punctations per annulus, lips quadrangular with eight pinnae, labial probolae bifurcate with divergent prongs surrounded by pinnae, pharynx with corpus 2.5–4.0 times isthmus length, post-vulval uterine sac 1.4–2.2 times the corresponding body diameter, and female and male tails conical, bearing a conical mucro with acute terminus. The phylogenetic position of this and related species of the genus Nothacrobeles is discussed. Additionally, bacteria (Pasteuria) and fungi (Catenaria, Nematocida) feeding on N. lanceolatus are showed including light microscopy and scanning electron microscopy illustrations.

Lake Teletskoye (West Siberia, Russia) is inhabited by a sympatric pair of whitefish, with each member of the pair being characterized by different feeding habits. Coregonus lavaretus pidschian (Gmelin, 1789) is a large ‘benthivorous’ form, while C. l. pravdinellus (Dulkeit, 1949) is a small ‘planktivorous’ form. Fish were collected from the end of August to the middle of September in 2017 and 2019–2020 in the north part of Lake Teletskoye. For the ‘benthivorous’ form the prevalence, intensity and abundance of T. crassus ranged from 22.4% to 51.9%, 1.9–2.8 and 0.4–1.3, respectively, whereas the same indices for the ‘planktivorous’ form ranged from 94.7% to 97.5%, 4.2–4.8 and 4.0–4.7, respectively. The level of prevalence of infection and abundance of T. crassus in muscle was relatively stable among studied years for both forms. The level of prevalence was higher in the years 2019 and 2020 than in 2017 for the ‘benthivorous’ form, whereas for the ‘planktivorous’ form this index did not change during the studied years. For the first time, a partial sequencing of the cox1 gene (593 bp) for T. crassus was sequenced. All 15 plerocercoids of T. crassus were represented by four haplotypes.

Although the efficacy of triclabendazole treatment against Fasciola gigantica has been shown before in cattle and buffaloes, there appears to be no published report on the efficacy of triclabendazole in impala or other antelope species. As part of a health monitoring programme at Mulungushi International Conference Centre, Lusaka, Zambia, a coprological examination was undertaken to investigate the helminthological status of captive impala (Aepyceros melampus). Of 39 fresh coprological samples, 46% contained F. gigantica. The source of infection was identified to be a fountain within the grounds of the conference centre. Lymnaea natalensis, collected from the study site, were induced to shed cercariae, and were thus confirmed as the snail intermediate host. In managing this disease, triclabendazole at 6 mg/kg was administered together with the feed bait. Water from the pond was drained; vegetation within it cleared and the pond allowed to dry for 1 week before water was replaced. Three weeks post-treatment, faecal examination revealed that the Fasciola had been cleared. To the best of our knowledge, this is a first case of Fasciola spp. infection reported in captive wild impala in Zambia and provides evidence that triclabendazole may be delivered to free-ranging antelope using medicated bait.

Parasites can have strong effects on invertebrate host behaviour, fecundity and survival in marine ecosystems. However, parasites are often poorly documented and still rarely integrated into marine ecological modelling; comprehensive surveys of infection in marine invertebrates are sporadic at best. For example, rock crabs are an important part of Californian coastal ecosystems, both as regulators of mussel populations and non-native species, and as prey items for predators like sea otters, but their parasite communities and potential effects on crab population dynamics are seldom studied or understood. Here, we present the first report of infection by the trematode Helicometrina nimia in the economically and ecologically important red rock crab (Cancer productus) and Pacific rock crab (Romaleon antennarium). As intermediate hosts, they are a missing link for infection by H. nimia in Californian fish that was unreported until now. Based on these findings, we advocate for further research into parasite diversity and their potential effects on ecologically and commercially important species.

The epidemiological picture of Taenia saginata infections in Kenya is fragmented with limited available data. Although Sarcocystis species are significant meat-borne parasites, few studies have explored their occurrence in Kenya. This study aimed to estimate the occurrence of bovine cysticercosis and screen for the presence of Sarcocystis spp. A meat inspection-based survey was conducted in ten abattoirs in Narok County, Kenya, and inspection for T. saginata cysticerci was limited to the Triceps brachii muscle. The apparent occurrence of the parasite was 5.4% (95% CI, 3.8, 7.6, n=573). Molecular confirmation of T. saginata was done via nested polymerase chain reaction targeting the mitochondrial 12S ribosomal RNA gene and restricted fragment length polymorphism. Sarcocystis species were identified using a multiplex polymerase chain reaction method targeting the 18S ribosomal RNA gene sequences and the mitochondrial cytochrome c oxidase subunit I gene. Of the 31 cystic lesions tested, 26/31 (83.9%) were confirmed to be T. saginata. Sarcocystis cruzi and S. hominis were detected in 8/31 (25.8%) and 1/31 (3.2%) of the cystic lesions, respectively. Co-infections of S. cruzi and T. saginata were found in 6/31 lesions (19.4%). The confirmation of bovine cysticercosis and S. hominis is suggestive of the presence of risky culinary and sanitation practices that facilitate transmission. This is the first report and molecular confirmation of Sarcocystis spp. in cattle in the country. The presence of both zoonotic S. hominis and pathogenic S. cruzi highlights an underexplored concern of veterinary and human health significance, warranting further epidemiological investigation.

An isolated population of 700 specimens initially described as Corynosoma strumosum (Rudolphi, 1802) Lühe, 1904 and currently reassigned to Corynosoma neostrumosum n. sp. was collected from one young male Caspian seal, Pusa caspica (Gmelin) in the southern land-locked Caspian Sea in April 2009. Collected worms were morphologically unique compared with those reported by other observers in open waters, especially in shape and distribution of proboscis hooks and trunk spines, dorso-ventral differences in proboscis hooks and their organization, the baldness of anterior proboscis, consistently smaller size of trunk and testes, larger eggs, the rough egg topography, epidermal micropores, and variations in the female gonopore. Molecular data from the internal transcribed spacer region of rDNA and the mitochondrial cox1 gene was also provided to supplement the morphological study of the new species.

The species of the genus Dirofilaria are filarial parasites causing zoonotic infections in humans with an increasing incidence in temperate and tropical areas of the world. Due to its classification as a vector-borne disease, the most important factors influencing dirofilariosis transmission are those related to climate, such as temperature and humidity. However, other factors linked with human behaviour can influence the distribution of the parasite. Although the Russian Federation could be considered as a non-suitable area for Dirofilaria spp. transmission due to its climatic conditions, one third of the human cases of dirofilariosis have been declared in this country. Here, seroepidemiological data on human dirofilariosis for five different regions distributed throughout the Russian Federation (Rostov, Moscow, Ekaterinburg, Yakutia and Khabarovsk) were obtained. A total of 940 serum samples from totally random donors living in these areas were analysed by enzyme-linked immunosorbent assay for the detection of anti-Dirofilaria immitis immunoglobulin G antibodies. Similar seroprevalence data ranging from 3.41% in Yakutia to 6.95% in Khabarovsk, with no significant correlation with climatic data of yearly average temperature and rainfall from these regions were found. These results suggest that other factors probably related to human behaviour, and not only climatic conditions, might be facilitating the spread of human dirofilariosis in these areas.

In this paper we re-describe Trichuris muris based on morphological data following isolation from two commensal rodent species, Mus musculus from Mexico and Rattus rattus from Argentina. Furthermore, we provide a molecular characterization based on mitochondrial (cytochrome c oxidase subunit 1 mitochondrial gene) and nuclear (internal transcribed spacer 2 region) markers in order to support the taxonomic identification of the studied specimens of T. muris from M. musculus. We distinguished T. muris from 29 species of Trichuris found in American rodents based on morphological and biometrical features, such as the presence of a spicular tube, length of spicule, size of proximal and distal cloacal tube and non-protrusive vulva. We suggest that spicular tube patterns can be used to classify Trichuris species in three groups. Considering that the diagnosis among the species of this genus is mainly based on morphometry, this proposal represents a relevant contribution. We provide molecular studies on two markers, making this the first contribution for T. muris in the Americas. This study makes an important contribution to the integrative taxonomy of cosmopolitan nematode species, and its correct determination from the parasitological study of commensal rodents.

Trichinellosis is a re-emerging worldwide foodborne zoonosis. Oxidative stress is one of the most common detrimental effects caused by trichinellosis. In addition, Trichinella infection poses an infinite and major challenge to the host’s immune system. Resistance and side effects limit the efficiency of the existing anti-trichinella medication. Given that concern, this work aimed to investigate the anti-helminthic, antioxidant, anti-inflammatory and immunomodulatory effects of resveratrol and zinc during both phases of Trichinella spiralis infection. Sixty-four Swiss albino mice were divided into four equal groups: non-infected control, infected control, infected and treated with resveratrol, and infected and treated with zinc. Animals were sacrificed on the 7th and 35th days post-infection for intestinal and muscular phase assessments. Drug efficacy was assessed by biochemical, parasitological, histopathological, immunological, and immunohistochemical assays. Resveratrol and zinc can be promising antiparasitic, antioxidant, anti-inflammatory, and immunomodulatory agents, as evidenced by the significant decrease in parasite burden, the significant improvement of liver and kidney function parameters, the increase in total antioxidant capacity (TAC), the reduction of malondialdehyde (MDA) level, the increase in nuclear factor (erythroid-derived 2)-like-2 factor expression, and the improvement in histopathological findings. Moreover, both drugs enhanced the immune system and restored the disturbed immune balance by increasing the interleukin 12 (IL-12) level. In conclusion, resveratrol and zinc provide protection for the host against oxidative harm and the detrimental effects produced by the host’s defense response during Trichinella spiralis infection, making them promising natural alternatives for the treatment of trichinellosis.

Entomopathogenic nematodes (EPNs) are closely associated with Popillia japonica and potentially used as their biological control agents, although field results proved inconsistent and evoked a continual pursuit of native EPNs more adapted to the environment. Therefore, we surveyed the Azorean Archipelago to isolate new strains of Heterorhabditis bacteriophora and to evaluate their virulence against the model organism Galleria mellonella under laboratory conditions. Six strains were obtained from pasture and coastal environments and both nematode and symbiont bacteria were molecularly identified. The bioassays revealed that Az172, Az186, and Az171 presented high virulence across the determination of a lethal dose (LD50) and short exposure time experiments with a comparable performance to Az29. After 72 hours, these virulent strains presented a mean determination of a lethal dose of 11 infective juveniles cm-2, a lethal time (LT50) of 34 hours, and achieved 40% mortality after an initial exposure time of only 60 minutes. Az170 exhibited an intermediate performance, whereas Az179 and Az180 were classified as low virulent strains. However, both strains presented the highest reproductive potential with means of 1700 infective juveniles/mg of larvae. The bioassays of the native EPNs obtained revealed that these strains hold the potential to be used in biological control initiatives targeting P. japonica because of their high virulence and locally adapted to environmental conditions.

Urocystis prolifer Villot, 1880 is an intestinal parasite of Sorex spp. In the Palaearctic. There are significant differences in the descriptions of both adults and stages of ontogenesis of U. prolifer as described by various authors. The experimental infection of intermediate hosts with cestodes has been conducted. An overview of the geographical distribution, infestation of the definitive hosts and the development of the metacestode stages of U. prolifer are presented. The cestode is characterized by an extensive geographic area in the Palaearctic, wide host specificity and very high rates of infection of its definitive host. Urocystis prolifer has been recorded mostly in the taiga and forest zones of Palaearctic. Fourteen species of Sorex were registered as the definitive host. Redescription of U. prolifer and an amended generic diagnosis are provided. A complete description of the ontogeny from oncosphere to fully developed metacestode is given. Features of development of the metacestode are an asexual larval reproduction, the absence of the anterior and posterior obturator valve in the cyst of the fully developed urocyst, as well as excretory bodies.

Adult trematodes, morphologically similar to Haplosplanchnus pachysomus (Eysenhardt, 1829), were extracted from the intestine of Mugil cephalus Linnaeus, 1758, collected in the Black Sea basin. Morphological, morphometric and 28S ribosomal DNA (rDNA) partial sequence data were obtained for these trematodes following comparative analysis with previous data on this species. Worms from this study were morphologically identical to all previously reported H. pachysomus specimens from different locations. The results of the morphometric analysis indicated general similarity between H. pachysomus from the Black Sea and trematodes from Vietnam and Australia. Trematodes from the Black Sea and specimens from Spain were identical based on 28S rDNA partial sequences; however, these sequences differed from that of H. pachysomus from Vietnam and Australia by eight fixed substitutions. Overall, our results indicate that H. pachysomus from Spain and the Black Sea and from Vietnam and Australia can presently be considered as two cryptic species, one in Palaearctic and one in Indo-West Pacific regions. Our results provide a molecular base for including Haplosplanchnus purii in the genus Provitellotrema or to consider H. purii, P. crenimugilis and H. pachysomus within the same genus.