Autochthonous Angiostrongylus cantonensis, Angiostrongylus vasorum and Aelurostrongylus abstrusus infections in native terrestrial gastropods from the Macaronesian Archipelago of Spain

The presence of zoonotic relevant Angiostrongylus cantonensis infections has recently been reported in rat final hosts and gastropod intermediate hosts in Tenerife, Spain. However, data on A. cantonensis, Angiostrongylus vasorum and Aelurostrongylus abstrusus prevalences in endemic gastropods for other islands of the Macaronesian Archipelago are still missing. In order to fill this gap, we conducted an epidemiological study on terrestrial native slug (Plutonia lamarckii) and snail (Cornu aspersum, Theba pisana, Rumina decollata) species in 27 selected locations of Tenerife, Gran Canaria, El Hierro, Lanzarote, La Palma and Fuerteventura. Overall, 131 terrestrial gastropods were collected in winter/spring season 2018/2019 and examined for the presence of metastrongyloid lungworm larvae via artificial digestion. The current data revealed a total prevalence of 4.6% for A. vasorum, 3.8% for A. abstrusus and 0.8% for A. cantonensis. In Tenerife, three lungworm species were detected, thereby re-confirming A. cantonensis endemicity for this island. Prevalences of snails (C. aspersum) originating from El Hierro were 5% for A. abstrusus and 15% for A. vasorum, respectively, with larval burdens up to 290 larvae per specimen. This epidemiological study indicates the presence of human, canine and feline lungworm species in Macaronesia, Spain. The current data-particularly those on anthropozoonotic A. cantonensis-call for a regular large-scale monitoring on intermediate hosts, paratenic hosts and definitive hosts to prevent further spread of lungworm-related diseases in humans and animals.

Lungworm (Crenosoma goblei) Infection in Unweaned Free-Ranging Raccoons (Procyon lotor) in Washington State, USA

Larval parasites morphologically identified as Crenosoma goblei were found in orphaned raccoons (Procyon lotor) admitted to a wildlife rehabilitation center in Washington State, US. Partial 18S rRNA and cytochrome oxidase I gene sequences were most similar to other Crenosoma spp. Although commonly reported in free-ranging raccoons throughout much of the central and eastern US, this finding extends the range of C. goblei into the Pacific Northwest of North America. Fecal samples taken within 48 h of admission were positive for larvae in 70% (21/30) of individuals and in all five group samples taken from an additional 14 raccoons. Typically, Crenosoma spp. use an intermediate host, but the unweaned status of all the raccoons in this report suggests a potential direct, possibly vertical, route of transmission. Serial fecal analysis of pooled samples collected over several subsequent months demonstrated spontaneous resolution of larval shedding. Adult worms and gross evidence of pneumonia were detected in the lungs of several juvenile raccoons at necropsy, and verminous pneumonia was confirmed histologically in the single case submitted. Clinical signs directly attributable to verminous pneumonia were not seen in most actively shedding raccoons, suggesting that subclinical disease among juveniles may be common.

Crenosoma vulpis in red foxes (Vulpes vulpes) in Northern Italy

Crenosoma vulpis, the fox lungworm, is a nematode parasite of wild and domestic canids belonging to the super-family Metastrongyloidea. A survey of infection was carried out examining 88 red foxes (Vulpes vulpes) obtained during the regular hunting season (2014-2015) from the Emilia-Romagna region of Italy. Carcasses were stored frozen (- 21 °C) prior to necropsy. Lungs were examined for the presence of adult worms by dissection of the trachea, bronchi, and bronchioles, and then the lung tissue was examined for first-stage larvae (L1) by the Baermann method. No adult stages were detected, but L1, identified based on morphology as Crenosoma vulpis, were recovered from 28.4% (25/88) of the fox lungs. No significant differences in infection were found based on sex or geographical distribution. A brief review on C. vulpis report in red foxes in Italy and other European countries was also carried out.

The invasive giant African snail Lissachatina fulica as natural intermediate host of Aelurostrongylus abstrusus, Angiostrongylus vasorum, Troglostrongylus brevior, and Crenosoma vulpis in Colombia

BACKGROUND

Several metastrongyloid lungworms are unreported pathogens in Colombia. Angiostrongylus vasorum and Crenosoma vulpis target the cardiopulmonary system of domestic and wild canids. Aelurostrongylus abstrusus and Troglostrongylus brevior infect felids and considering that six wild felid species exist in Colombia, knowledge of feline lungworm infections is important for their conservation. The zoonotic metastrongyloids Angiostrongylus costaricensis and Angiostrongylus cantonensis can cause severe gastrointestinal and neurological diseases. Angiostrongylus costaricensis has been reported in Colombia, while Ang. cantonensis is present in neighbouring countries. Research on the epidemiology of metastrongyloids in Colombia and South America more broadly requires evaluating the role that gastropods play as intermediate hosts in their life cycles. This study assessed the prevalence of metastrongyloid larvae in populations of the invasive giant African snail, Lissachatina fulica, in Colombia.

METHODOLOGY/PRINCIPAL FINDINGS

A total of 609 Lissachantina fulica were collected from 6 Colombian municipalities. The snails were then cryo-euthanized, artificially digested and the sediments examined microscopically for the presence of metastrongyloid larvae. Based on morphological characteristics 53.3% (56/107) of the snails from Puerto Leguízamo (Department of Putumayo) were infected with Ael. abstrusus larvae, 8.4% (9/107) with Ang. vasorum larvae, 6.5% (7/107) with T. brevior larvae and 5.6% (6/107) with C. vulpis larvae, being the region with highest prevalences of the four species. Snails from Andes (Department of Antioquia) and Tulúa (Department of Valle del Cauca) were positive for Ang. vasorum larvae with a prevalence of 4.6 (11/238) and 6.3% (4/64), respectively. Species identifications were confirmed by PCR and sequencing.

CONCLUSIONS/SIGNIFICANCE

This epidemiological survey reports for first time the presence of Ael. abstrusus, T. brevior, C. vulpis and Ang. vasorum in L. fulica in a number of regions of Colombia.

Validity of genus Perostrongylus Schlegel, 1934 with new data on Perostrongylus falciformis (Schlegel, 1933) in European badgers, Meles meles (Linnaeus, 1758): distribution, life-cycle and pathology

BACKGROUND

A century of debates on the taxonomy of members of the Metastrongyloidea Molin, 1861 led to many reclassifications. Considering the inconstant genus assignation and lack of genetic data, the main aim of this study was to support the validity of the genus Perostrongylus Schlegel, 1934, previously considered a synonym of Aelurostrongylus Cameron, 1927, based on new molecular phylogenetic data and to understand its evolutionary relationships with other metastrongyloid nematodes.

RESULTS

Specimens of lungworm collected from European badgers in Germany, Romania and Bosnia and Herzegovina were morphologically and molecularly (rDNA, cox1) characterized. From a phylogenetic standpoint, Perostrongylus is grouped with high support together with the genera Filaroides van Beneden, 1858 and Parafilaroides Dougherty, 1946 and includes probably two species: Perostrongylus falciformis (Schlegel, 1933), a parasite of Meles meles in Europe and P. pridhami (Anderson, 1962), a parasite of Neovison vison in North America. Perostrongylus and Aelurostrongylus are assigned to different clades. Aelurostrongylus becomes a monotypic genus, with the only species Aelurostrongylus abstrusus (Railliet, 1898). In addition, we provide morphological and morphometric data for the first-stage (L1), second-stage (L2), and third-stage (L3) larvae of P. falciformis and describe their development in experimentally infected Cornu aspersum snails. The pathological and histopathological lesions in lungs of infected European badgers are also described. This is the first record of P. falciformis in Romania.

CONCLUSIONS

Molecular phylogenetic and morphological data support the validity of the genus Perostrongylus, most probably with two species, P. falciformis in European badgers and P. pridhami in minks in North America. The two genera clearly belong to two different clades: Perostrongylus is grouped together with the genera Filaroides and Parafilaroides (both in the family Filaroididae Schulz, 1951), whereas Aelurostrongylus belongs to a clade with no sister groups.

First report on Protostrongylus cuniculorum (Nematoda: Protostrongylidae) in the European brown hare (Lepus europaeus Pallas, 1778 L.) from Bulgaria

A nematode species from the Protostrongylidae family, unknown in the parasite fauna of Bulgaria until now, was found in the bronchi of a European brown hare (Lepus europaeus Pallas, 1778 L.) from a southwestern region of the country. At first the systematic identification of the found specimens was attributed to two possibilities-Protostrongylus terminalis Passerini (1884) Schulz, Orlow & Kutass, 1933 and Protostrongylus cuniculorum (Joyeux & Gaud, 1946) Schulz & Kadenazii, 1949. The autonomy of these two species was discussed based on data available in the literature. Morphological and morphometric data about the male and female specimens are provided in the present materials. After comparing these data with the ones available in the literature, the helminths were related to the species P. cuniculorum. P. cuniculorum is reported for the first time as part of the helminth fauna of the European brown hare from Southeastern Europe and Bulgaria in particular.

Characterization of the complete mitochondrial genome of Metastrongylus salmi (M. salmi) derived from Tibetan pigs in Tibet, China

The present study was designed to determine and analyze the mt genomes of Metastrongylus salmi (M. salmi), and reveal the phylogenetic relationships of this parasite using mt DNA sequences. Results showed that the complete mt genome of M. salmi was 13722 bp containing 12 protein-coding genes (cox1-3, nad1-6, nad4L, atp6 and cytb), 22 transfer RNA genes, and 2 ribosomal RNA genes (rrnL and rrnS). The overall A+T content was 73.54% and the nucleotide composition was A (23.52%), C (6.14%), G (19.60%), T (50.02%), and N (UCAG) (0.73%). A total of 4237 amino acids are encoded from the Tibetan isolates of M. salmi mt genomes. The ATA was predicted as the most common starting codon with 41.7% (5/12 protein genes); and 11 of the 12 protein genes were found to have a TAG or TAA translation termination codon. By clustering together the phylogenetic trees of Tibetan M. salmi and Austrian M. salmi, the M. salmi isolated from Tibetan pigs was found to be highly homological with that stemmed from Austrian one. This information provides meaningful insights into the phylogenetic position of the M. salmi China isolate and represents a useful resource for selecting molecular markers for diagnosis and population studies.

Varestrongylus (Nematoda: Protostrongylidae), lungworms of ungulates: a phylogenetic framework based on comparative morphology

Varestrongylus Bhalerao, 1932 comprises ten valid lungworm species infecting wild and domestic ungulates from Eurasia and North America. Here, we present a phylogenetic hypothesis for the genus based on morphological characters in a broader context for the family Protostrongylidae and discuss species relationships and aspects of character evolution. Phylogenetic analysis of 25 structural attributes, including binary and multistate characters, among the 10 species of Varestrongylus resulted in one fully resolved most parsimonious tree (61 steps; consistency index = 0.672, retention index = 0.722, and consistency index excluding uninformative characters = 0.667). Varestrongylus forms a monophyletic clade and is the sister of Pneumostrongylus, supporting recognition of the subfamily Varestrongylinae. Monophyly for Varestrongylus is diagnosed by six unequivocal synapomorphies, all associated with structural characters of the copulatory system of males. Varestrongylus pneumonicus is basal, and sister to all other species within the genus, which form two subclades. The subclade I contains V. sagittatus + V. tuvae and V. qinghaiensis + V. longispiculatus. Subclade II contains V. alpenae, V. capricola, V. capreoli, and V. eleguneniensis + V. alces. Both subclades are diagnosed by two unambiguous synapomorphies. Highlighted is the continuing importance of phylogenetic assessments based on comparative morphology as a foundation to explore the structure of the biosphere across space and time.

Lungworms and gastrointestinal parasites of domestic cats: a European perspective

With the exception of Aelurostrongylus abstrusus, feline lungworms have been poorly studied. Information on their distribution is patchy and mostly limited to case reports. In this study, the occurrence of feline lungworms and co-infecting gastrointestinal parasites has been investigated in 12 European countries (i.e. Austria, Belgium, Bulgaria, France, Greece, Hungary, Italy, Portugal, Romania, Spain, Switzerland and the United Kingdom). An average of 10 domestic cats, with regular outdoor access, was sampled each month for 12months, and freshly passed faeces were collected. Stools were processed using a McMaster assay and a quantitative Baermann-Wetzel method. Animals positive for lungworms and/or gastrointestinal parasites were treated with a formulation containing fipronil, (S)-methoprene, eprinomectin, and praziquantel (Broadline®, Merial), and re-sampled 28days post-treatment. The association between lungworm infection and risk factors was analysed using statistical medians/means and the efficacy of the treatment against each lungworm species was assessed. Of 1990 cats sampled, 613 (30.8%) were positive for at least one parasite, while 210 (10.6%) were infected by lungworms. The prevalence of lungworm infection varied between the sampled sites, with the highest recorded in Bulgaria (35.8%) and the lowest in Switzerland (0.8%). None of the cats from Austria or the United Kingdom were infected by lungworms. Aelurostrongylus abstrusus was the species most frequently detected (78.1%), followed by Troglostrongylus brevior (19.5%), Eucoleus aerophilus (14.8%) and Oslerus rostratus (3.8%). The overall efficacy of the treatment was 99% for A. abstrusus and 100% for T. brevior, O. rostratus and E. aerophilus. Data presented provide a comprehensive account of the diagnosis, epidemiology and treatment of feline lungworms in Europe, as well as of the occurrence of co-infections by gastrointestinal parasites.

Complete mitochondrial genome of Angiostrongylus malaysiensis lungworm and molecular phylogeny of Metastrongyloid nematodes

Angiostrongylus malaysiensis is a nematode parasite of various rat species. When first documented in Malaysia, it was referred to as A. cantonensis. Unlike A. cantonensis, the complete mitochondrial genome of A. malaysiensis has not been documented. We report here its complete mitogenome, its differentiation from A. cantonensis, and the phylogenetic relationships with its congeners and other Metastrongyloid taxa. The whole mitogenome of A. malaysiensis had a total length of 13,516bp, comprising 36 genes (12 PCGs, 2 rRNA and 22 tRNA genes) and a control region. It is longer than that of A. cantonensis (13,509bp). Its control region had a long poly T-stretch of 12bp which was not present in A. cantonensis. A. malaysiensis and A. cantonensis had identical start codon for the 12 PCGs, but four PCGs (atp6, cob, nad2, nad6) had different stop codon. The cloverleaf structure for the 22 tRNAs was similar in A. malaysiensis and A. cantonensis except the TΨC-arm was absent in trnV for A. malaysiensis but present in A. cantonensis. The Angiostrongylus genus was monophyletic, with A. malaysiensis and A. cantonensis forming a distinct lineage from that of A. costaricensis and A. vasorum. The genetic distance between A. malaysiensis and A. cantonensis was p=11.9% based on 12 PCGs, p=9.5% based on 2 rRNA genes, and p=11.6% based on 14 mt-genes. The mitogenome will prove useful for studies on phylogenetics and systematics of Angiostrongylus lungworms and other Metastrongyloid nematodes.

Crenosoma vulpis in wild and domestic carnivores from Italy: a morphological and molecular study

Crenosoma vulpis is a metastrongyloid nematode primarily associated with respiratory tract infections of red foxes in North America and Europe. Sporadic cases have also been reported in domestic dogs. The present study aimed to provide morphological, molecular, and epidemiological data on the geographical distribution of this nematode throughout Italy. From 2012 to 2014, 12 of the 138 foxes examined, three dogs and one badger scored positive for C. vulpis. Forty adults were isolated from foxes and the badger, whereas first-stage larvae were detected in the three dogs. All specimens were morphologically identified as C. vulpis, and 28 nematodes were also molecularly characterized by sequencing mitochondrial (12S ribosomal DNA (rDNA)) and nuclear (18S rDNA) ribosomal genes. Four haplotypes were identified based on the 12S rDNA target gene, with the most representative (78.5%) designated as haplotype I. No genetic variability was detected for the 18S rDNA gene. The molecular identification was consistent with the distinct separation of species-specific clades inferred by the phylogenetic analyses of both mitochondrial and ribosomal genes. Data herein reported indicates that C. vulpis has a wide distribution in foxes from southern Italy, and it also occurs in dogs from southern and northern regions of the country. Practitioners should consider the occurrence of this nematode in the differential diagnosis of canine respiratory disease, particularly in dogs living close to rural areas where foxes are present.

Resurrection and redescription of Varestrongylus alces (Nematoda: Protostrongylidae), a lungworm of the Eurasian moose (Alces alces), with report on associated pathology

BACKGROUND

Varestrongylus alces, a lungworm in Eurasian moose from Europe has been considered a junior synonym of Varestrongylus capreoli, in European roe deer, due to a poorly detailed morphological description and the absence of a type-series.

METHODS

Specimens used in the redescription were collected from lesions in the lungs of Eurasian moose, from Vestby, Norway. Specimens were described based on comparative morphology and integrated approaches. Molecular identification was based on PCR, cloning and sequencing of the ITS-2 region of the nuclear ribosomal DNA. Phylogenetic analysis compared V. alces ITS-2 sequences to these of other Varestrongylus species and other protostrongylids.

RESULTS

Varestrongylus alces is resurrected for protostrongylid nematodes of Eurasian moose from Europe. Varestrongylus alces causes firm nodular lesions that are clearly differentiated from the adjacent lung tissue. Histologically, lesions are restricted to the parenchyma with adult, egg and larval parasites surrounded by multinucleated giant cells, macrophages, eosinophilic granulocytes, lymphocytes. The species is valid and distinct from others referred to Varestrongylus, and should be separated from V. capreoli. Morphologically, V. alces can be distinguished from other species by characters in the males that include a distally bifurcated gubernaculum, arched denticulate crura, spicules that are equal in length and relatively short, and a dorsal ray that is elongate and bifurcated. Females have a well-developed provagina, and are very similar to those of V. capreoli. Morphometrics of first-stage larvae largely overlap with those of other Varestrongylus. Sequences of the ITS-2 region strongly support mutual independence of V. alces, V. cf. capreoli, and the yet undescribed species of Varestrongylus from North American ungulates. These three taxa form a well-supported crown-clade as the putative sister of V. alpenae. The association of V. alces and Alces or its ancestors is discussed in light of host and parasite phylogeny and host historical biogeography.

CONCLUSIONS

Varestrongylus alces is a valid species, and should be considered distinct from V. capreoli. Phylogenetic relationships among Varestrongylus spp. from Eurasia and North America are complex and consistent with faunal assembly involving recurrent events of geographic expansion, host switching and subsequent speciation.

Varestrongylus eleguneniensis sp. n. (Nematoda: Protostrongylidae): a widespread, multi-host lungworm of wild North American ungulates, with an emended diagnosis for the genus and explorations of biogeography

BACKGROUND

A putative new species of Varestrongylus has been recently recognized in wild North American ungulates based on the ITS-2 sequences of larvae isolated from feces during a wide geographic survey. No taxonomic description was provided, as adult specimens were not examined.

METHODS

Lungworm specimens were collected in the terminal bronchioles of muskoxen from Quebec, and a woodland caribou from central Alberta, Canada. The L3 stage was recovered from experimentally infected slugs (Deroceras spp.). Description of specimens was based on comparative morphology and integrated approaches. Molecular identity was determined by PCR and sequencing of the ITS-2 region of the nuclear ribosomal DNA, and compared to other protostrongylids.

RESULTS

Varestrongylus eleguneniensis sp. n. is established for a recently discovered protostrongylid nematode found in caribou (Rangifer tarandus), muskoxen (Ovibos moschatus) and moose (Alces americanus); hosts that collectively occupy an extensive geographic range across northern North America. Adults of Varestrongylus eleguneniensis are distinguished from congeners by a combination of characters in males (distally bifurcate gubernaculum, relatively short equal spicules not split distally, a strongly elongate and bifurcate dorsal ray, and an undivided copulatory bursa) and females (reduced provagina with hood-like fold extending ventrally across prominent genital protuberance). Third-stage larvae resemble those found among other species in the genus. The genus Varestrongylus is emended to account for the structure of the dorsal ray characteristic of V. eleguneniensis, V. alpenae, V. alces and V. longispiculatus.

CONCLUSIONS

Herein we describe and name V. eleguneniensis, a pulmonary protostrongylid with Rangifer tarandus as a primary definitive host, and which secondarily infects muskoxen and moose in areas of sympatry. Biogeographic history for V. eleguneniensis and V. alpenae, the only two endemic species of Varestrongylus known from North America, appears consistent with independent events of geographic expansion with cervid hosts from Eurasia into North America during the late Pliocene and Quaternary.

[The first record of the lungworm, Metastrongylus asymmetricus (Noda, 1973), in the wild boar from Poland]

A total of 17 wild boars (Sus scrofa) shot in the Miechów hunting area (southern Poland) during two consecutive winters of 2008, were surveyed for the presence of lung nematodes of the genus Metastrongylus. The animals were necropsied, their lungs removed, divided into smaller parts and examined along the bronchial tubes. The parasites found were identified based on their morphologic characters. The prevalence of the lungworms reached 76.5%, and all of the 13 infected animals harboured two (one boar) or more parasite species. The mean number of parasites in an individual boar was 58.7, ranging from 6 to 250 specimens. Out of 250 identified lungworms, 48.8% was identified as M. pudendotectus, 32.8% were M. elongatus, and 14.0% belonged to M. salmi, whereas 4.4% (i.e. 10 females and 2 males) were M. asymmetricus. Until recently, only four Metastrongylus species have been recorded from Poland, namely M. elongatus, M. pudendotectus, M. salmi and M. confusus. The presently reported finding of M. asymmetricus constitutes the first record of this species in Poland.

Bighorn Sheep, a New Host Record for Parelaphostrongylus odocoilei (Nematoda: Protostrongylidae)

Larval nematodes with a dorsal spine on the tail were recovered from fecal samples of California bighorn sheep (Ovis canadensis californiana) in northeastern Washington State, USA. The identity of these dorsal-spined larvae (DSL) was established by single-strand conformation polymorphism (SSCP) analyses of a partial fragment of the first internal transcribed spacer of the ribosomal DNA. The SSCP profiles of individual DSL from bighorn sheep were compared with those of DSL of five protostrongylid species (Parelaphostrongylus andersoni, P odocoilei, P. tenuis, Elaphostrongylus rangiferi, and Muellerius capillaris) but were identical to only those of P. odocoilei. This study represents the first confirmed identification of P. odocoilei in bighorn sheep.

Restoration of Parafilaroides (Dougherty, 1946) (Nematoda: Metastrongyloidea) with description of two new species from pinnipeds of eastern central Pacific

The lungs of a northern elephant seal, Mirounga angustirostris (Gill, 1866), and Pacific harbor seal, Phoca vitulina richardii (Gray, 1864), from the eastern central Pacific, central California coast, were examined for parasites. This represents the first thorough description and identification of Parafilaroides species from northern elephant seals and Pacific harbor seals on the west coast of North America. From this study, 2 new species of Filaroides (Parafilaroides) are described, illustrated, and differentiated by shape of vaginal sphincter, body morphometrics, and spicule shape from the 4 existing, recognized species in the subgenus. In addition, the subgenus Parafilaroides is proposed to be reestablished to full generic status in the Filaroididae based on the presence of caudal papillae and DNA.

The first report of Aelurostrongylus falciformis in Norwegian badgers (Meles meles)

The first report of Aelurostrongylus falciformis (Schlegel 1933) in Fennoscandian badgers is described. Routine parasitological examination of nine Norwegian badgers, at the National Veterinary Institute during 2004 and 2005, identified A. falciformis in the terminal airways of five of the animals. The first stage larvae (L1) closely resembled, in size and morphology, those of Angiostrongylus vasorum (Baillet 1866). The diagnosis for both A. falciformis and A. vasorum is frequently based on the identification of L1 in faeces or sputum. The potential for misclassification of an A. falciformis infection as A. vasorum, where larval identification is the only diagnostic method used, is discussed.

Single-strand conformation polymorphism (SSCP) analysis as a new diagnostic tool to distinguish dorsal-spined larvae of the Elaphostrongylinae (Nematoda: Protostrongylidae) from cervids

Single-strand conformation polymorphism (SSCP) was used to genetically differentiate morphologically indistinguishable first-stage larvae (L(1)) of the six species of elaphostrongyline nematodes. A partial fragment (317-336bp) of the first internal transcribed spacer (pITS-1) plus 5' flanking region (76bp of the 18S gene) of the nuclear ribosomal DNA (rDNA) was amplified from individual L(1) of known identity and subjected to SSCP. The results showed that the four species of elaphostrongylines found in North American cervids, Parelaphostrongylus tenuis, P. andersoni, P. odocoilei and Elaphostrongylus rangiferi, could be distinguished from one another based on their distinct (i.e. species-specific) SSCP profiles. In addition, E. alces, a species that occurs in moose in Fennoscandinavia, also had a distinct SSCP profile with respect to the other species of elaphostrongylines. However, the SSCP profiles of E. cervi could not be distinguished from those of E. rangiferi because of a lack of interspecific sequence differences in this region of the ITS-1. The distinct SSCP profiles for the other species were consistent with the interspecific differences in ITS-1 sequences, which ranged from 2 (between P. tenuis and P. andersoni) to 59bp (between genera). The pITS-1 SSCP approach was also used to identify unknown elaphostrongyline L(1) from different hosts and localities in North America. The ability to distinguish between L(1) of the four elaphostrongyline species that occur in North American cervids has important diagnostic and epidemiological implications.

A new species of Skrjabingylus Petrov, 1927 (Nematoda: Metastrongyloidea) from the frontal sinuses of the hooded skunk, Mephitis macroura (Mustelidae)

Skrjabingylus santaceciliae n. sp. is described based on specimens from the frontal sinuses of a hooded skunk, Mephitis macroura, collected from the Area de Conservación Guanacaste, Costa Rica. Skrjabingylus santaceciliae n. sp. differs from the other 5 species in the genus in having pointed spicule tips that lack a rounded or lobed formation and by lacking a prominent distal projection at the tail tip. Morphometric comparisons show that S. santaceciliae n. sp. is much smaller than the only other valid species from Mephitis, Skrjabingylus chitwoodorum Hill, 1939. Likewise, morphometric comparisons also distinguish S. santaceciliae n. sp. from other described Skrjabingylus species.

Phylogenetic analysis of the Metastrongyloidea (Nematoda: Strongylida) inferred from ribosomal RNA gene sequences

Phylogenetic relationships among nematodes of the strongylid superfamily Metastrongyloidea were analyzed using partial sequences from the large-subunit ribosomal RNA (LSU rRNA) and small-subunit ribosomal RNA (SSU rRNA) genes. Regions of nuclear ribosomal DNA (rDNA) were amplified by polymerase chain reaction, directly sequenced, aligned, and phylogenies inferred using maximum parsimony. Phylogenetic hypotheses inferred from the SSU rRNA gene supported the monophyly of representative taxa from each of the 7 currently accepted metastrongyloid families. Metastrongyloid taxa formed the sister group to representative trichostrongyloid sequences based on SSU data. Sequences from either the SSU or LSU RNA regions alone provided poor resolution for relationships within the Metastrongyloidea. However, a combined analysis using sequences from all rDNA regions yielded 3 equally parsimonious trees that represented the abursate Filaroididae as polyphyletic, Parafilaroides decorus as the sister species to the monophyletic Pseudaliidae, and a sister group relationship between Oslerus osleri and Metastrongylus salmi. Relationships among 3 members of the Crenosomatidae, and 1 representative of the Skrjabingylidae (Skrjabingylus chitwoodorum) were not resolved by these combined data. However, members of both these groups were consistently resolved as the sister group to the other metastrongyloid families. These relationships are inconsistent with traditional classifications of the Metastrongyloidea and existing hypotheses for their evolution.

A retrospective study of 11 cases of lungworm (Didelphostrongylus hayesi) infection in opossums (Didelphis virginiana)

A juvenile, female North American opossum (Didelphis virginiana) died of verminous pneumonia caused by Didelphostrongylus haysei despite aggressive treatment with oral fenbendazole, corticosteroids, and antibiotics. This prompted a retrospective study of lungworm infection in opossums, during which 19 additional necropsy reports from opossums were reviewed. Including the subject of this report, a total of 11 (55%) of these cases included a diagnosis of lungworm infection. This diagnosis was considered to have contributed to death in eight out of the 11 cases (73%). Histologically, 10 of the 11 (91%) opossums had granulomatous bronchopneumonia with small to moderate numbers of adult nematodes in the airways and parenchyma. Four of the 11 (36%) opossums had free larvae within the parenchyma or terminal airways. Inflammation was usually associated with larvae, degenerating parasites, and nonintact adult nematodes. Superimposed bacterial pneumonia was evident in three animals, and sections of lung examined from all the opossums were characterized by moderate to severe smooth-muscle hyperplasia in airways, including terminal respiratory bronchioles and alveolar ducts. Nine animals had prominent medial smooth-muscle hyperplasia in small- and medium-sized arterioles. Lesions in other organs, particularly in liver, heart, and gastrointestinal tract, were frequently identified. Three animals had concomitant septicemia or bacterial bronchopneumonia (or both), which contributed to the cause of death. Seven animals had gastric nematodosis (Physaloptera sp.), although three of them had been treated with a 14-day course of fenbendazole.

Gallegostrongylus australis n. sp. (Nematoda: Angiostrongylidae) from Muridae in Australia, with zoogeographical considerations

Gallegostrongylus australis n. sp. (Nematoda: Angiostrongylidae) is described from subpleural nodules in the lungs of Rattus fuscipes, R. lutreolus and Mus domesticus in Australia. It is distinguished from G. andersoni occurring in gerbillids in West Africa by the shorter lengths of spicules and gubernaculum, and from G. ibicensis occurring in microtids and murids in Spain by the greater lengths of spicules and gubernaculum and the shorter distances from vulva and from anus to the caudal extremity of females. The parasite has been found only in 16 of 4,227 (prevalence 0.38%) animals representing at least 28 species of native and three species of introduced murid rodents throughout Australia. The genus Gallegostrongylus may be an old one, possibly originating in rats. By rafting and/or human activities the parasite appears to have been distributed around the world where it has encountered suitable intermediate hosts and available niches for colonisation of new definitive hosts. Consequently, morphologically similar but biologically distinct species have evolved in rodent hosts in West Africa, the western Mediterranean, and Australia.

Characterization of Otostrongylus circumlitus from Pacific harbor and northern elephant seals

Otostrongylus circumlitus (Railliet, 1899) from Pacific harbor seals (Phoca vitulina richardsi) and northern elephant seals (Mirounga angustirostris) were examined using morphological and molecular methods to determine whether northern elephant seals along the central California coast are infected by the same species of Otostrongylus as are Pacific harbor seals in the same area. Fixed nematodes were examined and measured using light microscopy. The polymerase chain reaction (PCR) was used to amplify and sequence the second internal transcribed spacer (ITS-2) and D3 expansion (26S) regions of ribosomal DNA of O. circumlitus from Pacific harbor and northern elephant seals. The ITS-2 region was also amplified from Parafilaroides sp. from the Pacific harbor seal, northern elephant seal, and California sea lion (Zalophus californianus) and used for restriction fragment length polymorphism (RFLP) analysis. Morphologically, it was not possible to distinguish O. circumlitus from Pacific harbor and northern elephant seals, and over a consensus length of 443 base pairs (bp) for ITS-2 and 321 bp for D3 the sequences of O. circumlitus from both hosts were identical. With the PCR-RFLP assay, it was possible to distinguish O. circumlitus from Parafilaroides sp. The results suggest that O. circumlitus is the same species in Pacific harbor and northern elephant seals, and molecular methods make it possible to distinguish this nematode from related nematodes.

Differentiation of dorsal-spined elaphostrongyline larvae by polymerase chain reaction amplification of ITS-2 of rDNA

Molecular genetics was used to devise the first reliable diagnostic tool for differentiating morphologically indistinguishable dorsal-spined, first-stage larvae (L1's) and other stages of the nematode protostrongylid subfamily Elaphostrongylinae. A polymerase chain reaction (PCR) assay employing specifically designed primers was developed to selectively amplify DNA of the ITS-2 region of the ribosomal gene. Amplification of the entire ITS-2 region differentiated between larvae of the genera Elaphostrongylus and Parelaphostrongylus, based on the lengths of fragments produced. Three sets of primers were designed and used successfully to distinguish larvae at the species level. Although it was demonstrated that one primer set in a single PCR assay was capable of distinguishing each of the three Parelaphostrongylus spp., a second primer set would be required for confirmation in routine diagnostic use. Two of the three primer sets were capable of amplifying DNA from all six elaphostrongyline species and of identifying Elaphostrongylus alces and Parelaphostrongylus odocoilei. Although two separate fragments were produced from each Elaphostrongylus cervi and Elaphostrongylus rangiferi, it was not possible to distinguish these two parasites from each other based on the fragment size. The use of various nematodes, hosts, and fecal controls demonstrated the reliability of the primers for all developmental stages including L1's, third-stage larvae, and adult worms. These primers also have potential for identifying other lungworms as was shown by the amplification of Umingmakstrongylus pallikuukensis, the muskox protostrongylid, and Dictyocaulus sp. from white-tailed deer. Although this assay may benefit from further refinement, its present design provides researchers, wildlife managers, clinicians, and animal health regulators with a practical tool for the control, management, and study of meningeal and tissue worms and their close relatives.

Evolutionary relationships among the protostrongylidae (Nematoda: Metastrongyloidea) as inferred from morphological characters, with consideration of parasite-host coevolution

The phylogeny of nematodes in the family Protostrongylidae (Nematoda: Metastrongyloidea) was reconstructed by cladistic analysis of 28 binary and multistate characters derived from comparative morphology. Analyses were hierarchical, and examined (1) relationships among genera, including 13 ingroup taxa and Metastrongylidae as an outgroup (single tree, 78 steps, consistency index [CI] = 0.705); and (2) relationships among genera and species groups, including 21 ingroup taxa and Metastrongylus apri as an outgroup (single tree, 76 steps, CI = 0.582). In the species-level tree, Protostrongylidae was divided into 2 major clades, 1 containing the subfamilies Muelleriinae (including the recently described Umingmtakstrangylus pallikuukensis), Elaphostrongylinae, and the Varestrongylinae (excluding Pneumocaulus kadenazii). Varestrongylus was paraphyletic as it included Pneumostrongylus calcaratus. The second major clade consisted of a paraphyletic group containing Protostrongylus spp. and Spiculocaulus leuckarti and, basal to this subclade, several other individual protostrongylid lineages. The various subclades generally correspond to the subfamilial divisions of the Protostrongylidae. The Neostrongylinae, however, is not supported as Neostrongylus and Orthostrongylus are not sister groups. Based on a large number of hypothesized synapomorphies, the elaphostrongylines appear to be a highly derived group of protostrongylids, a feature potentially correlated with their habitat localization in muscular and nervous tissues. The generic-level tree retained most of the primary structure revealed among the species but excluded the varestrongylines from the Muelleriinae + Elaphostrongylinae subclade. Artiodactyles of the family Cervidae are considered basal hosts for protostrongylids; secondary colonization in Caprini, Rupicaprini, and among lagomorphs is postulated.

Protostrongylid nematode infection of chamois (Rupicapra rupicapra) at the Bauges massif (French Alps)

From 1979 to 1985, protostrongylid infections (small lungworms) of chamois were studied at the Bauges hunting reserve, in the western Alps. Fifty-two chamois were necropsied on 24 sites and lung nematodes identified to species. From June to November 1985, a more detailed study was undertaken on four sites where chamois were the only ruminants. First-stage larvae excreted in feces and infection of snails intermediate hosts were monitored. The protostrongylid species were, arranged in decreasing order of prevalence, Neostrongylus linearis, Protostrongylus rupicaprae, Muellerius capillaris, and Muellerius tenuispiculatus. Intensity was higher in females than in males (in chamois aged 4 to 11 months compared with younger or older ones) in winter than in the other seasons. Intensity of infection increased as chamois were located at lower altitudes. The snail intermediate hosts were, in decreasing order of importance, Helix pomatia, Cepaea sylvatica and Arianta arbustorum.

Study by ribosomal DNA ITS 2 sequencing and RAPD analysis on the systematics of four Metastrongylus species (Nematoda:Metastrongyloidea)

Four species of lungworms of the Metastrongylus genus are found sympatrically in the lungs of the wild boars (Sus scrofa L.) on the Chambord game reserve (France): Metastrongylus asymmetricus, M. confusus, M. pudendotectus, and M. salmi. These species are difficult to identify using morphological characters alone, and epidemiological evidence raises doubt about the existence of 4 distinct species. Two molecular approaches (sequencing of ribosomal DNA Internal Transcribed Spacer 2 [ITS 2] and Random Amplified Polymorphic DNA assay [RAPD]) were used to evaluate the genetic similarities between the 4 taxa. The ITS 2 sequences of M. salmi and M. confusus were identical, whereas the sequences of the other species were distinct. On the other hand, RAPD analysis indicated unambiguously that the 4 species are genetically different. These results reveal the limitation of using only 1 molecular approach for taxonomic studies and indicate the need to examine different regions (ribosomal, mitochondrial DNA) in the genome of a species in complement with morphological and epidemiological data.

Protostrongylidae in Cervidae and Ovibos moscatus: a clustering based on isoelectric focusing on nematode body proteins

Isoelectric focusing for protein separation and evaluation by Unweighted Pair Group Method with Arithmetic averages (UPGMA) clustering was tested as an alternative to a morphological approach to taxonomical studies of the family Protostrongylidae and the genus Elaphostrongylus. These analyses revealed a close relationship among first stage protostrongylid larvae from roe deer, muskoxen and Varestrongylus alces first stage larvae. Furthermore, first stage larvae collected from moose faeces and adult Elaphostrongylus in moose were found related. Adult Elaphostrongylus in moose and reindeer maintained their separate taxonomical status.

Gastropod intermediate hosts of Parelaphostrongylus tenuis (Nematoda: Metastrongyloidea) from northwestern Indiana

Thirteen species of terrestrial gastropods from the Kingsbury State Fish and Wildlife Area, Indiana, were examined for the presence of third-stage larvae (L3s) of the meningeal worm, Parelaphostrongylus tenuis, during the summers of 1987 and 1988. Three (Deroceras laeve, Discus cronkhitei, and unidentified species of Cochlicopa [= Cionella]) were infected. Prevalence of infection was low, 1.1% and 2.7% in 1987 and 1988, respectively. The highest prevalence was 5.5% in Cochlicopa spp.; however, most of the larvae from this host were recently molted second-stage larvae (L2s). Attempts to identify foci of infection based on vegetation cover, soil pH, and replaceable calcium levels in the soil were unsuccessful. This is the first report of P. tenuis from Indiana.

Species of the genus Elaphostrongylus parasite of Swedish cervidae. A description of E. alces n. sp

A description of Elaphostrongylus alces n. sp., a parasite of moose (Alces alces L.), is given. The main features differing E. alces n. sp. from the other two investigated species are the bottle shaped oesophagus and the oval bursa, which is about 150 microns x 200 microns. E. rangiferi Mitskevith, 1960, a parasite of reindeer (Rangifer tarandus tarandus L.) and E. cervi Cameron, 1931, a parasite of red deer (Cervus elaphus L.) have both a club shaped or cylindrical oesophagus and a circular bursa. The bursa of E. rangiferi is about 160 microns in diameter, and the bursa of E. cervi is about 190 microns. Each species has been found only in its normal host.

Systematics of species referred to the genus Angiostrongylus

Based on morphological criteria of the male bursa, angiostrongylid nematodes often placed in the genus Angiostrongylus Kamensky (1905) were found to be heterogeneous, comprising species which are relegated to 5 distinct genera: Angiostrongylus Kamensky, 1905 (syn. Haemostrongylus Railliet and Henry, 1907); Parastrongylus Baylis, 1928 (syn. Pulmonema Chen, 1935, Rattostrongylus Schulz, 1951, Morerastrongylus Chabaud, 1972, Chabaudistrongylus Kontrimavichus and Delyamure, 1979); Angiocaulus Schulz, Orlov and Kutass, 1933; Gallegostrongylus Mas-Coma, 1977 (syn. Thaistrongylus Ohbayashi, Kamiya and Bhaibulaya, 1979 n. syn); and Stefanskostrongylus Drozdz, 1970. These genera all contain species located primarily in specific host groups: Angiostrongylus in carnivores; Parastrongylus in rodents (Muridae), Angiocaulus in mustelids; Rodentocaulus in rodents (Cricetinae), Gallegostrongylus in rodents (Muridae), and Stefanskostrongylus in insectivores. Species in each genus include: Angiostrongylus (A. vasorum, A. raillieti, A. chabaudi); Parastrongylus (P. tateronae, P. cantonensis, P. mackerrasae, P. sandarsae, P. sciuri, P. petrowi n. comb., P. dujardini, P. schmidti, P. costaricensis n. comb., P. malaysiensis n. comb., P. ryjikovi n. comb., P. siamensis n. comb.); Angiocaulus (A. gubernaculatus, A. ten n. comb., A. sp. Caballero, 1951); Rodentocaulus (R. ondatrae) and Gallegostrongylus (G. ibicensis, G. andersoni, G. harinasutai n. comb.). Angiostrongylus pulmonalis is likely similar to Stefanskostrongylus soricis and is transferred to this genus. Angiostrongylus minutus is removed to Stefanskostrongylus.

Procyonostrongylus muelleri gen. et sp. n. (Metastrongyloidea: Angiostrongylidae) from the raccoon (Procyon l. lotor)

Procyonostrongylus muelleri gen. et sp. n. from under the epithelium of the epiglottis of Procyon l. lotor is distinguished by 1) the absence of lips; 2) a highly developed reinforced bursa with a deep terminal incision; 3) highly developed toothlike dorsal rays; 1) greatly reduced externodorsal rays; and 5) the terminal or subterminal anus and vulva in the female.

Elaphostrongylus cervi Cameron 1931 (Nematoda: Metastrongyloidea) in caribou (Rangifer tarandus caribou) of Newfoundland

Elaphostrongylus cervi Cameron 1931 is identified for the first time in North America from woodland caribou (Rangifer tarandus caribou) in Newfoundland where up to 88% of animals were infected. First-stage nematode larvae identical to those of E. cervi occur in faeces of barren ground caribou (R. t. groenlandicus) of the Kaminuriak herd and of woodland caribou in northern Labrador, Ontario, and Manitoba, suggesting that the parasite is widespread in Rangifer in Canada.In clinically normal caribou, adult E. cervi were found beneath the skin and in fascia of the thoracic musculature. Verminous pneumonia caused by nematode eggs and larvae in the lungs and diffuse lymphocytic leptomeningitis over the brain and spinal cord were consistent aspects of infection. A 10-month-old caribou calf exhibiting neurologic signs had numerous E. cervi among thoracic and cervical muscles but none in the central nervous system. Accumulations of lymphocytes, eosinophils, and histiocytes in the subarachnoid and perineurium of lateral nerves in the posterior region of the spinal cord and destruction of axons in the cauda equina may explain the clinical signs observed.

[The occurrence of broncho-pulmonary nematodes in sheep from Emilia-Romagna]

In the present investigations 510 sheep have been examined for the presence of lungworm larvae: 342 (67,05%) of them proved positive. The identification of the parasites demonstrated the presence of Dyctiocaulus filaria in 18,62% of the examined animals, Muellerius capillaris in 50%, Cystocaulus ocreatus in 26,86% and Protostrongylus spp. in 12,35%. All positive flocks were positive for two or more genera of lungworms.

A redescription and neotype designation for Parelaphostrongylus odocoilei (Nematoda: Metastronglyoidea)

Parelaphostrongylus odocoilei is redescribed from worms collected from the type host (Odocoileus hemionus columbianus) in California, as well as material from experimentally infected mule deer (O. h. heminus) in Alberta. A single male specimen from the California material is designated as the neotype of P. odocoilei, the type species of Parelaphostrongylus. The male copulatory structures of the 3 species of Parelaphostrongylus (P. tenuis, P. anderscni, and P. odocoilei) are reviewed and a key for the identification of males is provided.

The resurrection of Filariopsis van Thiel 1926 (Metastrongyoidea: Filaroididae) for filaroidid lungworms from primates

Filariopsis van Thiel 1926 is resurrected and redefined to include those species formerly in Filaroides van Beneden 1858 which have been described from primate hosts. Included in Filariopsis are F. asper van Thiel 1926. F. arator Chandler 1931 (= F. cebi Gebauer 1933), F. cebuellae (Liu 1965) n.comb., F. gordius (Travassos 1921) n.comb., and F. barretoi (Travassos 1921) sp.inq. Filariopsis is characterized by possessing, on the male tail, two pairs of large subventral postanal papillae with multiple nerves and indications of being lobed, and up to two pairs of smaller, single, posterior papillae.

[Metastrongylidae parasites of European Soricidae. Description of Paracrenosoma combesi n. sp., from Crocidura russula Hermann, 1780 (author's transl)]

Description of Paracrenosoma combesi n. sp. (Skrjabingylinae), a lung parasite from the common white-toothed shrew Crocidura russula Hermann, 1780 in Spain, and differentiation from the only european species of the same genus, Paracrenosoma skrajabini (Pologentsev, 1935). Description of Stefanskostrongylus soricis (Soltys, 1954) (Angiostrongylinae) from the bronches of the pygmy shrew Sorex minutus Linnaeus, 1766, in Spain and comparison with the data of the same species in Oriental Europe.

Metastrongyles (Nematoda: Metastrongyloidea) of fisher (Martes pennanti) from Ontario

Fisher (Martes pennanti) collected from central Ontario were examined for metastrongyles. Trilobostrongylus bioccai Anderson, 1963 was found in 21%; Crenosoma petrowi Morozov, 1939 in 15%; and Sobolevingylus sp., Romanov, 1952 in 2%.

A protostrongylid nematode (Strongylida: Protostrongylidae) in woodland caribou (Rangifer tarandus caribou)

First-stage protostrongylid larvae found in faeces of woodland caribou (Rangifer tarandus caribou) in northwestern Ontario and Manitoba may be larvae of Elaphostrongylus sp., a well-known agent of neurologic disease in reindeer (Rangifer tarandus tarandus) of Eurasia.

Didelphostrongylus hayesi gen. et sp. n. (Metastrogyloidea: Filaroididae) from the opossum, Didelphis marsupialis

Didelphostrongylus hayesi gen. et sp. n. from the opossum, Didelphis marsupialis, is distinguished from other genera of the Angoistrongylinae by the structure of the dorsal and lateral rays, complex gubernaculum, and ovoviviparity. Third-stage larvae developed in Mesodon perigraptus and Triodopsis albolabris. The prepatent period was 22 days in experimentally infected opossums.

[Protostrongylus (Protostrongylus) rufescens boevi, a new subspecies, parasite of the respiratory apparatus of chamois]

A nematode parasitic of bronchial system of Rupicapra rupicapra (chamois) of Parco Nazionale del Gran Paradiso (Italian Western Alps) is described and the name Protostrongylus (Protostrongylus) rufescens boevi subspecies nova, is proposed.

Lungworms (Metastrongyloidea: Pseudaliidae) of harbor porpoise Phocoena phocoena (L. 1758)

Lungworms were collected from 60 harbor porpoises shot at sea during May to August of 1970 and 1971 in the Bay of Fundy. These have been compared with related species from other odontocetes in order to evaluate the literature on pseudaliids and provide a consistent treatment of the family. This study also gives data on the occurrence of lungworms in odontocetes from Canadian waters. Keys to genera and selected species of pseudaliids in cetaceans are included.The following are redescribed: Pseudalius inflexus (Rudolphi 1808), Stenurus minor (Kuhn 1829), Torynurus convolutus (Kuhn 1829), Halocercus invaginatus (Quekett 1841), and H. taurica Delyamure, in Skrjabin 1942 from harbor porpoise, Phocoena phocoena, collected in eastern Canada; Stenurus globicephalae Baylis and Daubney 1925 from Globicephala melaena, G. macrorhyncha, and Grampus griseus (new host record); Stenurus arctomarinus Delyamure and Kleinenberg 1958 and Pharurus pallasii (van Beneden 1870) n. comb, from Delphinapteras leucas; Torynurus dalli (Yamaguti 1951) from Phocoenoides dalli; and Pharurus alatus (Leuck-art 1848) from Monodon monoceros. Pseudalius inflexus, H. taurica, and S. arctomarinus are reported for the first time from North American hosts; S. globicephalae, P. pallasii, P. alatus, and all the pseudaliids from Phocoena phocoena are reported from new host localities.Torynurus alatus is considered a synonym of Pharurus alatus. Stenurus arcticus (including previously proposed synonyms Strongylus arcticus, Pseudalius arcticus) is considered a synonym of Pharurus pallasii.Halocercus ponticus Delyamure 1946 is considered synonymous with H. invaginatus.

Filaroides hirthi sp. n. (Nematoda: Metastrongyloidea) from the lung of the dog

Filaroides hirthi sp. n. is smaller than previously described species of the genus Filaroides v. Beneden, 1858, and differs from F. milksi Whitlock, 1956, with which it is most likely to be confused, in having shorter, slightly stouter spicules with a broader proximal knob for attachment of the retractor muscles.

The genus Crenosoma (Nematoda: Metastrongyloidea) in new world mammals

Study of types and other specimens of Crenosoma from the lungs of carnivores indicates that there are only six known valid species in the New World, namely: C. vulpis (Dujardin 1844) Railliet 1915; C. potos Buckley 1930; C. petrowi Morozov 1939 (= ? C. schulzi Gagarin 1958); C. mephitidis Hobmaier 1941 (= C. microbursa Wallace 1941, C. zederi Goble 1942, C. canadensis Webster 1964); C. goblei Dougherty 1945; C. hermani Anderson 1962. C. petrowi is reported for the first time in the New World, in the fisher Martes pennanti Erxleben and the badger Taxidea taxus (Schreber). Sobolevingylus coloradoensis (Olsen 1952) n. comb. (= Crenosoma coloradoensis) is proposed. An illustrated key is provided for the separation of the various species.