Genus Syphacia Research Articles

MODERN DISTRIBUTION OF NEMATODES P. SYPHACIA (NEMATODA, OXYURIDAE) IN POPULATIONS OF MOUSE-LIKE RODENTS IN THE VORONEZH RESERVE

The mouse-like rodents, inhabiting natural and anthropogenic biocenoses, are sources and distributors of various helminth infections, including syphaciosis. Currently, more than ten species of nematodes of the genus Syphacia are registered in mouse-like rodents. Syphacia exhibit narrow, guest specificity, parasitizing, as a rule, in one or three species of mouse-like rodents. The main sources of infection of rodents by these nematodes are vegetable feed, soil, forest litter. We have presented long-term (2000-2018) results of helminthological studies of mouse-like rodents, conducted in the Voronezh Reserve. At present, in the territory of mouse-like rodents, 5 species of Syphacia are registered: Syphacia agraria, S. obvelata, S. nigeriana, S. petrusewiczi, S. stroma. Taxonomic diagnosis of nematodes was carried out taking into account the guest specificity, localization in the host intestine, morphometric data, and also taking into account the structural features of the nematode head end. Nematodes of syphacia are noted in 7 host species: Mus musculus, Apodemus agrarius, Sylvemus flavicollis, Sylvemus uralensis, Myodes glareolus, Microtus agrestis, Microtus arvalis. The extensiveness of invasion ranges from 6 to 51% (on average, 30%).The study area is located in a densely populated region of the Central Black Earth region of Russia. Here, at the junction of natural and anthropogenic ecosystems, mouse-like rodents are a significant source of parasitic pollution. With a high number of rodents and high extensiveness of invasion by nematodes p. Syphacia, there is a significant accumulation of invasive beginning in the external environment, which increases the epidemiological and epizootological risks of this helminthiasis.

Phylogeny and biogeography of species of Syphacia Seurat, 1916 (Nemata : Oxyurida : Oxyuridae) from the Australian Bioregion

Pinworm nematodes of the genus Syphacia (Nemata : Oxyurida : Oxyuridae) have a global distribution, and infect the caecum of rodents. Within the Australian Bioregion, 17 species of Syphacia infect a range of rodent hosts. Pinworms are traditionally thought to have coevolutionary relationships with their hosts, but the evolution and dispersal of Australian rodents and their helminths remains unclear. This combination of factors allowed us to investigate the likely relationships of Australian Syphacia species based on phylogenetic analysis, overlaid with the ecology and relationships of host species. We conducted a phylogenetic analysis using morphological characters of the species of Syphacia from the Australian Bioregion in order to examine the relationships between species, and to investigate how host evolution and phylogeny could inform (or be informed) by parasite phylogeny. Application of the taxon pulse theory of parasite speciation by matching host species to parasites shed some light on the timing of speciation of rodent hosts. We found that species of Syphacia had reasonably close host–parasite relationships, with additional evidence for ecological fitting or host switching occurring. Evidence provided here suggests strongly that most elements of the Stockholm Paradigm are at play in structuring the relationships we observe in this pinworm–mammal system.

Syphacia sp. (Nematoda: Oxyuridae) in coprolites of Kerodon rupestris Wied, 1820 (Rodentia: Caviidae) from 5,300 years BP in northeastern Brazil

We present the results of paleoparasitological analyses in coprolites of Kerodon rupestris, rodent endemic to rocky areas of Brazil's semiarid region. The coprolites were collected from excavations at the archaeological site of Toca dos Coqueiros, in the National Park of Serra da Capivara, southeastern of state of Piauí. Syphacia sp. (Nematoda: Oxyuridae) eggs were identified in coprolites dated at 5,300 ± 50 years before present. This is the first record of the genus Syphacia in rodent coprolites in the Americas.

Studies on nematode parasites of fishes of Oinam lake Bishnupur district, Manipur, India

An extensive survey was done for fish nematode parasites of few economically important fishes of Oinam Lake, Bishnupur district, Manipur. 9 species of nematodes were encountered. They are Camallanus anabantis, Procamallanus (Procamallanus) saccobranchi, Paraquimperia manipurensis, Paragendria sp., juvenile stages of genus Syphacia, Haplonema, Spinitectus, Philometra and Parascarophis etc. Of these nematode species, Procamallanus (Procamallanus) saccobranchi, Paragendria sp and Haplonema sp. showed maximum abundance (14.28%) and Paraquimperia manipurensis, Parascarophis sp. showed minimum abundance (4.76%) of parasites. Among the fish species Anabas testudineus had highest percentage (50%) of parasites and Puntius sophore and Colisa labiosus had lowest percentage (1.25%) of parasites.

Phylogenetic relationships of rodent pinworms (genus Syphacia) in Japan inferred from 28S rDNA sequences

The 28S rDNA from nine species of the genus Syphacia collected in Japan was sequenced, and the phylogenetic relationship was inferred from multiple sequence alignment of 28S rDNA by the MAFFT program. Phylogenetic tree indicates that S. petrusewiczi, which was the only species belonging to the subgenus Seuratoxyuris, has diverged earlier than other rodent pinworms examined and was distantly separated from the others genetically. It was revealed that S. agraria and S. vandenbrueli, whose subgeneric status has not been specified, belonged to the subgenus Syphacia together with other 6 species. Syphacia montana from Clethrionomys, Eothenomys and Microtus was very closely related to S. obvelata from Mus, and that S. frederici from Apodemus and S. vandenbrueli from Micromys were comparatively closely related to the former two species. The phylogenetic relationship among the three species of Syphacia found in Japanese Apodemus was inconsistent with the biogeography of host rodents. The co-evolutionary relationship between pinworm species and their host rodents may not be so strict and host switching has probably occurred frequently during the course of evolution.

Helminths Collected From Imported Pet Murids, with Special Reference to Concomitant Infection of the Golden Hamsters with Three Pinworm Species of the Genus Syphacia (Nematoda: Oxyuridae)

A total of 210 individuals of 13 species belonging to 4 subfamilies of Muridae imported into Japan as pets were examined; 5 species of Syphacia (Nematoda: Oxyuridae), Aspiculuris tetraptera (Nematoda: Heteroxynematidae), and Rodentolepis nana (Cestoidea: Hymenolepididae) were collected. Concurrent infection with 3 pinworm species, Syphacia mesocriceti, Syphacia stroma, and Syphacia peromysci, was recorded for the first time in the golden hamster, Mesocricetus auratus. Syphacia mesocriceti was also identified in the desert hamster, Phodopus roborovskii, and S. peromysci was recovered from the fat-tailed gerbil, Pachyuromys duprasi, and the Cairo spiny mouse, Acomys cahirinus. From the pygmy mouse, Mus minutoides, an undetermined species closely resembling Syphacia megaloon and Syphacia ohtaorum, both parasitic in Mus spp., was collected. Females of another undetermined Syphacia sp. were observed in the greater Egyptian gerbil, Gerbillus pyramidum. All of the host-Syphacia associations, except S. mesocriceti in the golden hamsters, were recorded for the first time. It is suggested that overlapping breeding situations provided the opportunity for host switching by the pinworms.

Helminths Collected From Imported Pet Murids, with Special Reference to Concomitant Infection of the Golden Hamsters with Three Pinworm Species of the Genus Syphacia (Nematoda: Oxyuridae)

Helminths Collected From Imported Pet Murids, with Special Reference to Concomitant Infection of the Golden Hamsters with Three Pinworm Species of the Genus Syphacia (Nematoda: Oxyuridae)

Phylogenetic Relationships of Rodent Pinworms (genus <i>Syphacia</i>) in Japan Inferred from Mitochondrial CO1 Gene Sequences

Species of the genus Syphacia are considered to have generally co-evolved with their rodent hosts. This study determined partial sequences of the CO1 gene from several species in the genus Syphacia and discuss the relationships between pinworms and their hosts. Syphacia montana, which parasitizes Microtinae, was closely related to S. frederici and S. obvelata, which parasitize Murinae. Although both S. obvelata and S. ohtaorum parasitize rodents in the genus Mus, these two species were not found to be closely related to each other. Syphacia frederici, S. emileromani and S. agraria are all pinworms of the Apodemus species, but genetic affiliation between these three species was not indicated. These facts suggest that the co-evolutionary relationship between species of the genus Syphacia and their host rodents may not so strict and host switching has probably occurred during the course of evolution.

Syphacia (Syphacia) millardiae n. sp. (Nematoda: Oxyurida: Syphaciinae) from the Soft-Furred Field Rat, Millardia meltada, in India

Syphacia (Syphacia) millardiae n. sp. (Nematoda: Oxyuridae: Syphaciinae) is described based on specimens collected from a soft-furred field rat, Millardia meltada. This species is closely related to several other members of the genus Syphacia, also murid parasites. This species closely resembles Syphacia (Syphacia) obvelata, a cosmopolitan parasite of Mus musculus. Syphacia (Syphacia) millardiae n. sp. differs from S. obvelata in that females exhibit a cuticular ornamentation with varicose cuticular elevations between the cephalic nervous endings, smaller body width, smaller eggs, and a longer esophagus. Males exhibit a shorter body length, a longer tail with a shorter tail tip, a longer esophagus, and a longer gubernaculum than do males of S. obvelata.

The nematode fauna of long-nosed mice Oxymycterus spp. from the Bolivian Yungas.

During a long-term survey of the parasites of mammals from all over Bolivia, 44 individuals of Oxymycterus inca and 6 of Oxymycterus paramensis were collected and examined for parasites from the foothills and Eastern Cordillera (Los Yungas) of the Andes of Bolivia. Three species of nematode were found including, from the cecum, a previously unknown genus and species of pinworm, Caroloxyuris boliviensis n. gen, n. sp., aspidoderids representing Nematomystes rodentophilus, and from the stomach, Protospirura numidica criceticola. These helminths occurred in prevalences of 25, 9, and 14%, respectively, in O. paramensis. Caroloxyuris boliviensis resembles species included in the genus Syphacia in the structure of the cephalic mask and copulatory organs, and the extension of lateral alae. However, males of this species possess only 2 mamelons on the ventral surface of the body. Caroloxyuris can be recognized as being distinct from both Helminthoxys and Rauschtineria in the ornamentation of the mamelons and the shape of cephalic mask. A redescription of N. rodentophilus is provided, and Nematomystes scapteromi is transferred from Ansiruptodera to Nematomystes.

Syphacia (Syphacia) sulawesiensisn. sp. andS. (S.) muris(Yamaguti 1935) (Nematoda Oxyuridae) collected fromRattus xanthurus(Gray 1867) (Rodentia Muridae) in North Sulawesi, Indonesia

Syphacia (Syphacia) sulawesiensis n. sp. and S. (S.) muris (Yamaguti 1935) were recorded from Rattus xanthurus (Gray 1867) in North Sulawesi, Indonesia. Syphacia sulawesiensis is readily distinguished from other members of the subgenus Syphacia and from those for which a subgeneric position has yet to be settled in that it has large vesicular lateral alae, an excretory pore positioned well to the rear, a short tail and apices of caudal papillae posterior to the midtail level in the male, and closely-set excretory pore and vulva in the female. This is the second species of the genus Syphacia Seurat 1916 found to be parasitic in Rattus Fischer 1803. The females of S. muris from R. xanthurus have a much larger body than those reported previously from other murid species.

Redescription of Syphacia mesocriceti (Nematoda: Oxyuroidea) Parasite of the Golden Hamster

The oxyuroid Syphacia mesocriceti Quentin, 1971, from the golden hamster, Mesocricetus auratus (Waterhouse, 1839), is described with the aid of light and scanning electron microscopy. Cephalic extremities of males and females differ from those of all other species of the genus Syphacia. Males and females have reduced lips and a triangular stoma but differ from species of the subgenus Syphatineria with similar features by having a flanged esophageal cuticle with serrated edges. The operculate eggs are large. Three mamelons on the previously undescribed males put this species in the subgenus Syphacia. Syphacia mesocriceti Quentin, 1971, originally was described from females collected in Alaska from laboratory-reared golden hamsters, Mesocricetus auratus (Waterhouse, 1839). Discovery of additional specimens including males in the same host made possible a complete description of this species. Additional information obtained with scanning electron microscopy (SEM) on cephalic structures and cuticles of both males and females permits comparison of this species with others in the genus reviewed by Ogden (1971). MATERIALS AND METHODS Nematodes, recovered from the cecum of hamsters reared in a commercial animal breeding establishment at Ontario, Canada, were fixed in hot 70% alcohol with 5% glycerin. Whole mounts were made by clearing and mounting in glycerin and sealing the cover slip with Glyceel (ESBE Laboratory Supplies, 3431 Bathurst St., Toronto 19, Ontario). The anterior end was removed and mounted en face in glycerin jelly. Nematodes were prepared for SEM by freeze-drying according to the method of Dick and Wright (1973) and viewed with a Cambridge Stereoscan electron microscope. The following description is based on 6 female and 3 male metatypes. Drawings were made with the aid of a camera lucida. All measurements are in microns unless otherwise stated. Syphacia mesocriceti Quentin, 1971

A Mouse Oxyurid, Syphacia obvelata, as a Parasite of Man

In December, 1918, the late Dr. A. F. Coutant sent me from Zamboanga, Philippine Islands, a sample of fecal material containing tapeworm segments for identification. The sample was from an American Bohemian child living in Zamboanga. She was one of a family of five, all of whom were heavily infested by the worm in question. Examination of the material showed the presence of eggs and of fragments of the rat tapeworm of man, murina (H. nana). This species, until recently regarded as very rare in man, has been found in the course of the hookworm investigations in the South to be fairly common. Indeed, the prophecy made by Dr. Stiles soon after the commencement of that work, that Hymenolepis nana will be found to be the commonest tapeworm in the United States has been amply justified. Its minute size and the failure of physicians to make routine feces examinations had resulted in its being very largely overlooked, until the intensive studies of the hookworm campaign incidentally brought it to light. Of the more recent statistics there may be cited the studies of Frey (1915), who found this tapeworm in 32.6 per cent. of the inmates of the Texas State Orphans' Home. This percentage was exceeded only by that of hookworm infestation in the same group of 270 children. While the tapeworm which had attracted attention thus proved to be one already noted in man, the search through the material led to the finding of eggs and two specimens of an Oxyurid hitherto unreported for man. Since the feces sample had been preserved by adding 6 to 10 per cent. formalin solution it is probable that the actual strength of the diluted solution did not exceed 3 to 4 per cent. Thus the fixation of the worms was imperfect, but careful comparison with specimens and with the detailed descriptions by Seurat (1916) have convinced me that the species under consideration is Syphacia obvelata (Fig. 1). This nematode has been until recently classed in the genus Oxyuris, but more critical work has resulted in its being separated by Seurat as the type of a new genus Syphacia. Like the tapeworms