A new genus of Nippostrongylinae (Nematoda: Heligmonellidae) from the water rat Scapteromys aquaticus (Sigmodontinae) in Argentina

A new genus of Nippostrongylinae, Malvinema n. gen., with 3 coparasitic species M. frederici n. sp., M. carolinae n. sp., and M. victoriae n. sp. from the intestine of the water rat, Scapteromys aquaticus Thomas (Rodentia: Muridae), from the northeast of Buenos Aires Province, Argentina, is proposed in this study. The new genus shows similarities to 2 Neotropical Nippostrongylinae: Carolinensis (Travassos, 1937) by some characters of the synlophe and Stilestrongylus Freitas, Lent and Almeida, 1937, by the pattern of the caudal bursa. It is characterized by a synlophe with triple or quadruple gradient of size of the ridges, lateromedian, decreasing from the largest left and right ridges. The gradient situated in the right ventral quadrant is always present. The caudal bursa shows a pattern of type 1-4. Malvinema frederici possesses a synlophe with 17 ridges and an axis of orientation inclined at 45 degrees from the sagittal axis; M. carolinae possesses a synlophe with 22-24 ridges and an axis of orientation almost merged with the sagittal axis. Both species have a caudal bursa with the right lobe enlarged transversally. Malvinema victoriae possesses a synlophe with 22-24 ridges, an axis of orientation inclined at 45 degrees from the sagittal axis, and a caudal bursa with the right lobe enlarged vertically.     

Vexillata liomyos n. sp. (Nemata: Ornithostrongylidae) from Liomys pictus (Rodentia: Heteromyidae) from Mexico, with comments on the synlophe of Vexillata armandae.

Individuals of a new species of Vexillata were collected from the small intestines of Liomys pictus from the Estaci6n de Biología Chamela, in Jalisco State, Mexico. The new species shows an array of characters that allow us to recognize it as a member of Vexillata; however, it can be distinguished from other species of the genus in that males possess an asymmetrical caudal bursa, females possess a characteristic cuticular inflation at the level of the ovijector, and both sexes possess a synlophe with 9 ridges at the midbody. Additional detail of the synlophe of Vexillata armandae Gardner et al., 1994 from Chaetodipus hispidus in New Mexico shows that both sexes have 12 cuticular ridges just posterior to the cephalic inflation, and in the posterior region of the body, females have 9 ridges of equal size while males possess 11 equal-sized ridges. In both sexes, the carene disappears at the posterior end of the body.     

Tadaridanema delicatus (Schwartz, 1927) n. gen., n. comb. (Trichostrongylina: Molineidae) parasite of Molossidae bats

On the basis of the revision of the type material of Anoplostrongylus delicatus Schwartz, 1927, and new specimens collected from Tadarida brasiliensis mexicana (Saussure, 1860) in 4 arid localities from Mexico, we describe a new genus (Tadaridanema n. gen.), to which A. delicatus is transferred (as Tadaridanema delicatus (Schwartz, 1927) n. gen., n. comb.). This new genus differs from all other genera included in Anoplostrongylinae by having ray 2 larger than ray 3. In addition, T. delicatus can be differentiated from the type species of Anoplostrongylus (Anoplostrongylus paradoxus (Travassos, 1918)) because it possess vestibular branches equal in length, cephalic inflation divided into 2 regions, and synlophe with many small ridges at the midbody level, whereas in T. delicatus, vestibular branches are equal in size, cephalic inflation is simple in structure, and the synlophe has only 2 well-developed dorsal cuticular ridges.     

Two new species of Nippostrongylinae (Nematoda,Trichostrongylina) parasites of Cricetomys gambianus and Arvicanthis niloticus (Muridae) from Senegal

Two new Nippostrongylinae (Heligmosomoidea, Heligmonellidae) originating from Senegal are described. Heligmonina bioccai n. sp., a parasite of Cricetomys gambianus (Cricetomyinae) found in the surroundings of Dakar and Neoheligmonella bai n. sp., a parasite of Arvicanthis niloticus (Murinae) from the Province of Richard Toll. H. bioccai n. sp. is related to H. hybomysi (Durette-Desset, 1966) a parasite of Hybomys univittatus from the Central African Republic by some characteristics of the caudal bursa and of the synlophe. They are the only two species with the same pattern of caudal bursa: type 1-3-1 for the right lobe, 2-3 for the left lobe, and with the same number and disposition of the cuticular ridges at mid-body in the female. The two species are differentiated by the size (three times smaller in H. hybomysi), the ratio of spicule length on body length (7.6% versus 17% in H. hybomysi) and by a different synlophe in male and posterior part of female. N. bai n. sp. is differentiated from the closely related species N. dielmensis Diouf, Ba and Durette-Desset, 1997, also a parasite of Arvicanthis niloticus from Senegal by rays 8 arising asymmetrically on the dorsal ray and by the deirids situated at the same level as the excretory pore.     

Suttonema delta n. g., n. sp. (Nematoda: Trichostrongylina: Heligmosomoidea) from Oxymycterus rufus (Rodentia: Sigmodontinae) in Argentina

A new nippostrongyline, Suttonema delta n. g., n. sp., is described from the intestine of Oxymycterus rufus (Rodentia: Sigmodontinae) from Argentina, in a host from which trichostrongylid nematodes were hitherto unknown. The new genus is very similar to Stilestrongylus Freitas, Lent & Almeida, 1937 and Malvinema Digiani, Sutton & Durette-Desset, 2003, both parasites of Neotropical sigmodontines, in the features of the caudal bursa (with a pattern of type 1-4, asymmetrical with hypertophied right lobe) and the presence of cephalic structures resembling cuticular cordons. The larval synlophe is also identical to that of Stilestrongylus freitasi Durette-Desset, 1968. The new genus is differentiated by an adult synlophe with few ridges (9-12 at mid-body) of two different types: small, rounded ridges without cuticular support on the dorsal side, and pointed ridges of unequal size on the ventral side and in lateral fields. It is also characterised by the presence of comaretes on the left ventral and ventral fields of the synlophe.     

Trichostrongylina (Nematoda) from Malagasy Muridae. I--Description of two new species of Heligmonellidae in Nesomys spp

Two new species of Heligmonellidae, Heligmonina wrightae n.sp. (Nippostrongylinae) and Nesomystrongylus fissicauda n.gen., n. sp. (Brevistriatinae) are described from Madagascar in Nesomys rufus and N. audeberti (Muridae). In Nesomys audeberti, the species are coparasites. Heligmonina wrightae is differentiated from all the other species of the genus, except H. malacomysi Sakka & Durette-Desset, 1988, by the ratio of the length of the spicules on the length of the body (25-27.8% versus 9.5-7%). It differs from H. malacomysi by the pattern of the caudal bursa and by the angle of the axis of orientation of the cuticular ridges on the sagittal axis. Nesomystrongylus fissicauda is related to the genus Fissicauda Durette-Desset & Krishnasamy, 1976, by the absence of the carene, by the ridges discontinuous on all the sides of the body and by the deeply divided dorsal ray. It differs from this genus by a different structure of the ridges, by the pattern of the caudal bursa, (very tiny rays 2 and strongly developed rays 3, rays 8 arising from common trunk of rays 2 to 6) and by the presence of a caudal tip in the female.     

Description of two new species of Nippostrongylinae (Nematoda, Trichostrongyuna, Heligmosomoidea) coparasites in Arvicanthis ansorgei (Muridae) from Cameroon

In the small intestine of a single Arvicanthis ansorgei from Cameroon, two new species of Nippostrongylinae were found: Neoheligmonella zero n. sp. and Heligmonina comerounensis n. sp. N. zero belongs to the Neoheligmonella species in which the right dorsal ridge is poorly developed. Among these species, N. bainae (Durette-Desset, 1970), a parasite of Steatomys opinus from Burkina Fasso, is a closely related species. It is differentiated by the presence of vulvar alae, the ratio uterus length/body length and the separation of rays 2 and 3 at two thirds of their length. N. zero is also closely related to N. kenyae (Yeh, 1958) a parasite of Rattus rattus kijabius from Kenya by the pattern of the caudal bursa and the ratio spicules length/body length. The synlophe of N. kenyae was not described in detail but it is differentiated from N. zero by the position of the excretory pore, situated just posteriorly to the nerve ring and in the female by the ratio ovejector length/body length which is smaller. H. camerounensis n. sp. is characterised by the ratio dorsal ridges/ventral ridges which is 4/7. It is differentiated from the species of which the synlophe has not been described by the pattern of the caudal bursa (type 1-4 with tendancy 1-3-1). It is the first report of Nippostrongylinae species in Cameroon and the first record of a species of the genus Heligmonina in an Arvicanthis.     

A new species of Oswaldocruzia (Molineidae: Nematoda) in Chaunus marinus (Amphibian: Bufonidae) (Linneaus, 1758) from Brazil

Oswaldocruzia belenensis n. sp. (Strongylida: Molineidae) from the small intestine of Chaunus marinus (L.) from Belém, Pará State, Brazil is described and illustrated by light and scanning electron microscopy. Oswaldocruzia belenensis n. sp. is a neotropical species of this genus, harboring caudal bursa Type II, spicules divided in 3 branches, i.e., a blade, shoe, and fork. The blade is divided in 4 points, of which at least 2 are bifurcated. Cervical alae are absent; there is a simple cephalic vesicle and synlophe with low ridges perpendicular to the body without chitinous supports. The most closely related species are O. bonsi and O. lescurei. Oswaldocruzia belenensis n. sp. differs from O. lescurei and O. bonsi by the number and location of cephalic papillae, rays 2-3 and 5-6 running parallel and slightly separated, ray 6 not overlapping ray 8, and body structure morphometry. Oswaldocruzia belenensis n sp. also differs from O. lescurei by the discontinuity of the longitudinal ridges, the number of subdivisions of the blade, and the absence of extra processes at the bifurcation level of the fork of the spicules. The new species differs from O. bonsi by male and female body dimensions, the symmetry of the caudal bursa, dimension and subdivisions of the spicules without extra processes of the fork, 2 extra processes at the distal division of the blade, and location of ray 7 at the anterior margin of the cloacal aperture. Oswaldocruzia belenensis n. sp. represents the 82nd species assigned to the genus.     

Parasitism of two zoonotic reservoirs Dasyprocta leporina and D. fuliginosa (Rodentia) from Amazonas, with Trichostrongylina nematodes (Heligmonellidae): description of a new genus and a new species

A new genus and a new species of Heligmonellidae nematodes are described parasiting the stomach of three agoutis (two Dasyprocta fuliginosa and one D. leporina) captured in the middle and high Negro river microregion, state of Amazonas, Brazil. The new genus, as well as its type-species, are closely related to the trichostrongylids included in Fuellebornema, particularly on what concerns the pattern of the caudal bursa, but differing from them by the characteristics of the synlophe, that presents a poorly developed carene, when compared to the referred number of body ridges in Freitastrongylus n. gen. and consequently in F. angelae n. sp.,in which the ridges are well developed and the carene at mid-body has a similar size when compared to the ridge situated in front of the right field (ridge no. 5). Caudal bursa is of the type 1-4, with rays 9 shorter than rays 10, with a very long genital cone.     

New Pudicinae (Trichostrongylina, Heligmosomoidea), Pudica ctenomydis n. sp. parasite of Ctenomys talarum (Rodentia: Octodontidae) from Argentina

A total of 138 nematodes were found in the small intestine of Ctenomys talarum (Octodontidae) from Mar de Cobo, Argentina. A new nematode species, Pudica ctenomydis n. sp., is described. The new species more closely resembles P. pujoli Durette-Desset, 1990, parasite of Microcavia niata Thomas, from Bolivia. It can be distinguished from P. pujoli by the number of ridges and characteristics of the synlophe, the spicular morphology, differences in length between rays 9 and 10, and by the presence of a symmetrical caudal bursa and a cuticular expansion surrounding the body between vulva and anus in females.     

Three new species of the genus Oswaldocruzia Travassos, 1917 (Nematoda, Trichostrongylina, Molineoidea) parasites of Enyalius spp. (Iguanidae) from Brazil

Three new species of the genus Oswaldocruzia Travassos, 1917 belonging to the sub-family Molineinae are described from the stomach and/or the small intestine of Enyalius spp. from Brazil. They belong to group 6 of Ben Slimane, Chabaud & Durette-Desset (1996). In this group they share along with O. peruensis Ben Slimane, Verhaag & Durette-Desset, 1995, a parasite of Iguanidae from Peru the followings linked characters: (i) a caudal bursa of type II; (ii) cervical alae present; (iii) undulated cuticular ridges. The Peruvian species differs from the Brasilian species by the absence of a strut in the cervical alae, by a small number of cuticular ridges at mid-body and by a spicular fork with a ramified inner twig. Oswaldocruzio fredi n. sp., a parasite of the stomach and the small intestine of Enyalius iheringii, mainly differs from the two other species by the absence of the oesophageal ventral cuticular ridges. Oswaldocruzia benslimanei n. sp., a parasite of the small intestine of Enyalius bilineatus, differs from Oswoldocruzia burseyi n. sp., a parasite of the stomach of Enyalius perditus, by the division of the fork at 23.4 % of spicule length (versus 32 %), and the length of the blade longer than the fork. Oswoldocruzia subauricularis sensu Freitas, 1955 nec Rudolphi, 1819 and O. mazzai sensu Vicente, 1981 nec Travassos, 1935 should be considered as species inquirendae.     

A new species of Vexillata (Nematoda: Ornithostrongylidae) in Attwater's pocket gopher from Texas

Vexillata geomyos n. sp. is described as a parasite of Attwater's pocket gopher, Geomys attwateri (Geomyidae), from Welder Wildlife Refuge, Texas. The new species possesses 12 cuticular ridges; based on this character, it can be distinguished from 7 of the 13 species in the genus. From the 6 remaining species, V. geomyos can be differentiated because the dorsal ray in 3 of them (V. armandae, V. dessetae, and V. vexillata) has 2 short branches arising from main trunk, whereas dorsal ray of the new species lacks these branches. In addition, V. geomyos can be distinguished from V. brooksi because its spicules are divided at the tip (whereas in the new species, spicules are whole). The new species differs from V. legallae and V. convoluta in the number and arrangement of cuticular ridges at the posterior region of the body.     

Synlophe patterns of the Haemonchinae of ruminants (Nematoda: Trichostrongyloidea)

The pattern of longitudinal ridges (synlophe) on the external cuticular surface of trichostrongylid nematodes has been shown to be of value for distinguishing species and determining relationships among higher taxa. In the process of studying Mecistocirrus digitatus, the large stomach worm of bovids of Asia that has been imported and established in the Americas, we observed remarkably similar synlophe patterns to those described for 3 species of Haemonchus and to those we examined in a species of Ashworthius. In all 3 genera, the synlophe is absent from the posterior part of the body. Only in Haemonchus does the synlophe extend beyond midbody. In both M. digitatus and Ashworthius sidemi, the synlophe extends posteriorly only about 1/4 of body length. In all 3 genera, the synlophe consists of about 30 ridges in the region of the esophagus with variation among species in specific areas, including additional pairs of subventral and subdorsal ridges and different lengths of sublateral ridges. This information is useful for identifying species and determining relationships among these large stomach worm parasites of cattle, sheep, goats, and farmed and wild cervids.     

2 new species of Stilestrongylus (Nematoda: Heligmonellidae) parasites of Peromyscus (Rodentia: Cricetidae) from Mexico

Stilestrongylus peromysci n. sp. collected from Peromyscus difficilis (Hidalgo state, México), differs from other species in the genus in number of the spines (30) in the synlophe (both sexes) and because the eighth ray arises from the root of the ninth ray; S. hidalguensis n. sp. parasitised Peromyscus sp. and differs from all other congeneric species in the presence of 24 spines in the male synlophe and in the arrangement of the bursal rays (2-2-1 in the right lobe and 2-3 in the left lobe). A key to the species of Stilestrongylus is provided.     

Trichostrongylina (Nematoda) from Malagasy muridae. II--Description of two new species of Heligmonina (Heligmonellidae) in Nesomys rufus and Eliurus tanala

Two new species of Heligmonellidae from Madagascar are described, Heligmonina madagascariensis n. sp. in Nesomys rufus and Heligmonina tanala n. sp. in Eliurus tanala. Both species belong to the Heligmonina species with a pattern of type 1-3-1 for the right lobe of the caudal bursa and 1-4 for the left lobe. In H. madagascariensis, H. dupuisi (Desset, 1964) and H. praomyos Baylis, 1928, left ray 6 arises before ray 3 from the common trunk to rays 3 to 6 while in H. tanala and the other species, it arises at the same level. H. madagascariensis is differentiated from H. dupuisi and H. praomyos by the symmetry of the branches of the dorsal ray. H. tanala is differentiated from H. malacomys Sakka & Durette-Desset, 1988, the closely related species by a different pattern of the cuticular ridges at mid-body, by the sharpness of the tips of the spicules and by the ratio of the length of the spicules on the length of the body (6.9, 8.8% versus 25-27.8%). Heligmonina chippauxi (Desset, 1964) a parasite of Oenomys hypoxanthus from the Republic of Central Africa is considered a valid species.     

Description of a new species of Heligmonina Baylis, 1928 (Nematoda: Heligmonellidae) a parasite of Mastomys natalensis (Rodentia: Muridae) from Swaziland and new data on the synlophe of Heligmonina chabaudi (Desset, 1966)

A new species of heligmosomoid nematode belonging to the subfamily Nippostrongylinae Durette-Desset, 1970 is described: Heligmonina wakelini n. sp., a parasite from the small intestine of the commensal rodent Mastomys natalensis (Smith, 1834) from Swaziland. It differs from the most closely related species H. boomkeri Durette-Desset & Digiani, 2005 by the number of the cuticular ridges in the female synlophe (10 vs 12), the width of the left ala, larger than the body diameter in the male, and the inclination of the axis of orientation of the ridges in both sexes (53 degrees vs 70 degrees). New morphological data (head and synlophe) on Heligmonina chabaudi (Desset, 1964), also a parasite of Mastomys natalensis in the Republic of Congo, are provided in order to compare with the new species.     

Systematic position of some nearctic Heligmosomoidea (Nematoda: Trichostrongylina) from the U.S. National Parasite collection and their description

The systematic position of some heligmosomoid nematodes from rodents, deposited in the U.S. National Parasite Collection (USNPC), is revised, mainly through the study of their synlophe, which in all cases was unknown or insufficiently described. The material was registered as different species of Longistriata Schulz, 1926, a genus whose representatives are only parasitic in Holarctic insectivores. Longistriata norvegica Dikmans, 1935, parasitic in Rattus sp. becomes a synonym of Hassalstrongylus aduncus (Chandler, 1932). Specimens registered as Longistriata dalrymplei Dikmans, 1935, from Ondatra zibethicus, are confirmed to belong to Carolinensis (Travassos, 1937). Specimens registered as Longistriata noviberiae Dikmans, 1935, parasitic in Sylvilagus floridanus alacer, were found to belong to Vexillata, and Vexillata noviberiae n. comb. is here proposed. This is the first record of a species of Vexillata in a lagomorph. Other specimens registered as Longistriata norvegica, parasitic in Geomys floridanus austrinus, were also found to be an undescribed species of Vexillata (Hall, 1916), which is named Vexillata chitwoodi n. sp. This is similar to Vexillata chabaudi Yoyotte-Vado, 1972, Vexillata petteri Durette-Desset, 1970, Vexillata scorzai Guerrero, 1984 and Vexillata tejerai Guerrero, 1984, all having the same number of cuticular ridges (4 dorsal, 5 ventral) and the division of the dorsal ray at its apex. The most related species is V. chabaudi, which is differentiated from the new species by rays 4 not curved distally, by thick rays 8, and by a dorsal ray enlarged at the level of the arising of rays 8.     

Protospirura kaindiensis n. sp. (Spirura: Spiruridae) and other helminths from Pseudohydromys (Muridae: Hydromyinae) from Papua New Guinea

One cestode and 3 species of nematodes are recorded from Pseudohydromys murinus and Pseudohydromys occidentalis (Muridae: Hydromyinae), from Papua New Guinea, for the first time. Heterakis fieldingi (Ascaridida: Heterakidea) has previously been known from Australia. Odilia sp. resembles Odilia praeputialis in the orientation of the synlophe and the number and size of ridges but differs in the length of spicule and lack of a praepuce. Protospirura kaindiensis n. sp. (Spirurida: Spiruridae) is readily distinguished from all other members of the genus by the number and arrangement of caudal papillae and the length of the spicules.     

New Pudicinae (Nematoda,Heligmonellidae) parasite of Trichomys fosteri (Rodentia: Echimyidae) from Pantanal,Brazil

Pudica trichomysae n. sp. (Trichostrongylina, Heligmosomoidea, Helligmonellidae, Pudicinae) from the small intestine of Trichomys fosteri (Rodentia: Echimydae) from the Pantanal of Mato Grosso do Sul is described by light and scanning electron microscopy. Pudica trichomysae n. sp. is characterized by caudal bursa type 2–2-1, proportion of spicules length in relation to body length (SpL/BL) of 17 to 18% left and right, respectively. Dorsal ray divided at about the distal third into two branches, each branch divided into two long sub-branches, rays 9 and 10. Furthermore, this study shows for the first time details of the anterior region demonstrating papillae organization, amphids, derides, and opening of the excretory pore. The posterior end of the caudal bursa showed detail of the genital cone, papillae, and ray 1, and in the female, it showed interrupted ridges between the vulva and anus. In conclusion, the present species is the seventeenth described in the genus in South America and the first in Pantanal.