An annotated checklist of the genus Pterygodermatites Wedl, 1861 (Nematoda: Rictulariidae), with notes on hosts and geographical distribution.

Species of rictulariid nematodes belonging to the genus Pterygodermatites Wedl, 1861 are parasites of mammals with a wide geographical distribution. The taxonomy of this speciose genus is complex and based mainly on morphological traits of the cephalic structures and cuticular processes. Currently, the known species are allocated to five subgenera [P. (Paucipectines), P. (Neopaucipectines), P. (Multipectines), P. (Pterygodermatites) and P. (Mesopectines)], based on the classification proposed in 1969 by Quentin. Studies on life cycles, taxonomy, biogeography and association of these parasites with mammals peaked at the end of the 1960s. Although the momentum was lost, new species and geographic records have been added in the last 50 years. Therefore, an updated checklist of species of Pterygodermatites is presented here, based on a literature survey. Information on classification, geographical distribution and host range obtained for 68 species is presented, including a distribution map. Moreover, the main differential morphological traits related to each species are tabulated. More than 140 species from 10 different mammalian orders (Carnivora, Chiroptera, Didelphimorphia, Erinaceomorpha, Macroscelidae, Microbiotheria, Paucituberculata, Primates, Rodentia and Xenarthra) have been reported as hosts of Pterygodermatites spp. The taxonomic information here compiled can contribute to future studies on the biogeography, in addition to evolutionary and ecological aspects of this diverse but poorly known genus of parasitic nematodes of mammals.

RICTULARIA JIYEONI N. SP. (NEMATODA: RICTULARIIDAE) FROM THE STRIPED FIELD MOUSE, APODEMUS AGRARIUS, IN KOREA.

Rictularia jiyeoni n. sp. from the small intestine of the striped field mouse, Apodemus agrarius, in Korea, is described and illustrated. Specimens were studied using light and scanning electron microscopies. This rictulariid nematode is closest to the Rictularia species that have a reduced number of combs and spines. However, the new species can be differentiated from the other species of Rictularia by having 36-58 perioral denticles, a buccal capsule with a single esophageal tooth, and 37-44 pairs of combs and spines of which 32-37 are prevulvar and 5-11 are postvulvar.

Deep in the systematics of Camallanidae (Nematoda): using integrative taxonomy to better understand the phylogeny and consistency of diagnostic traits.

Due to conflicts between classic and molecular systematics of Camallanidae, different data types were used for the first time, to better understand the evolutionary history and taxa consistency within this family. Genetic [18S and 28S rDNA; cytochrome c oxidase subunit I (COI) mtDNA], morphological and life history traits were used to infer phylogenies using Bayesian inference, reconstructed from separated and concatenated datasets. The consistency of tree and morphological traits was evaluated using the consistency index. Characters were mapped on the trees and the phylogenetic informativeness of genetic markers was estimated. Phylogenetic informativeness of 18S provided better resolution for outer nodes, COI for inners and 28S had an intermediate profile. New sequences for two camallanid species were obtained. Phylogenies of genetic and concatenated data largely agreed, showing more divergence in the COI dataset, due to its higher mutation rate vs stable morphology for diagnosing higher taxa. No genus sustained monophyly. The lack of autapomorphy and phylogenetic proximity supported the partition of Batrachocamallanus as synonym of Procamallanus and Spirocamallanus, which should not be considered as subgenera. Although traits of buccal capsule, male tail, habitat, host and biogeographic were highly consistent, intrinsic patterns varied according to different taxa assemblages. Morphological systematics of Camallanidae, based on buccal capsule, is artificial for certain taxa.

Notes on Morphology and Life History of Probstmayria gombensis (Nematoda: Cosmocercoidea: Atractidae), Parasitic in Eastern Chimpanzees, Pan troglodytes schweinfurthii, in Bulindi, Uganda.

Probstmayria gombensis File, 1976 (Nematoda: Cosmocercoidea: Atractidae) individuals discharged in the feces of eastern chimpanzees, Pan troglodytes schweinfurthii, in Bulindi, Uganda, were examined morphologically. Adults and fourth-stage larvae, all females, found in the feces, and the third-stage larvae excised from the uterus of the gravid females were described. By close observation of the molting worms, it was considered that the uterine third-stage larvae attain molting phase, and then are laid to become fourth-stage larvae. Nutrients required for larval development in the uterus seem to be supplied by the mother after the eggshell is formed. After some growth in the host intestine, the fourth-stage larvae undergo the final molt to the adult stage. The genital primordium was very small in the early fourth-stage larvae but rapidly developed with embryonation in the pre-molt and molting phases. Such precocity suggests parthenogenetic reproduction without insemination by males. This style may enhance rapid autoinfection in the host intestine under the condition of male worm scarcity. Several ellipsoidal pseudocoelomocytes with granules of unknown function were found ventral to the intestine of the adults, fourth-stage larvae, and third-stage larvae.

Description and Molecular Differentiation of a New Skrjabinoptera (Nematode: Physalopteridae) from Eutropis macularia (Sauria: Scincidae) in North-Central Vietnam.

Skrjabinoptera vietnamensis n. sp. is described from specimens recovered from the stomach of Eutropis macularia in north-central Vietnam. The new species is characterized by the medium-sized male worms (6.7-8.7 mm in length and 154-182 µm in width) relative to known members of the genus, 2 pointed spicules of unequal length (87-112 µm and 56-72 µm in length), and 10 pairs of caudal papillae. Female worms are larger than male worms (10.7-18.4 mm in length and 264-411 µm in width), with the vulva situated in the anterior part, and embryonated, elliptical eggs, 35-46 µm long by 20-24 µm wide. Skrjabinoptera vietnamensis n. sp. represents the ninth species assigned to the genus and the first species recorded from the Oriental region. Partial sequences of the 18S ribosomal RNA gene (rDNA), and cytochrome c oxidase subunit 1 (COI) are provided for the new species. The molecular phylogenetic position of the genus Skrjabinoptera is briefly discussed.

Molecular Phylogeny of Thelastomatoidea (Nematoda) with the Description of a New Genus and Two New Species of Hystrignathidae Associated with Bess Beetles (Coleoptera: Passalidae) from Oaxaca, Mexico.

Bess beetles (Passalidae) display important roles in forestall ecosystems, particularly in energy extraction from dead wood. These organisms maintain complex biological interactions with their gut symbiotic communities, including bacteria, protists, and metazoans. Very little is known about symbionts since most of the species of Passalidae haven't been studied from a parasitological point of view. Here we describe a new genus and 2 new species of nematodes of the family Hystrignathidae associated with 2 beetle species of the tribe Proculini collected in the State of Oaxaca, Mexico. Tuhmai garciaprietoi n. gen., n. sp., found in Vindex agnoscendus is characterized by the presence of an unarmed cervical cuticle, a subcylindrical procorpus and a conspicuous isthmus, a monodelphic-prodelphic reproductive system, and a short subulate tail. Urbanonema osorioi n. sp., found in Verres hageni mainly differs from other species of Urbanonema by the number and disposition of cervical spines, as well as by a subulate tail. For each new taxon, we describe the external and internal morphology, and we generated molecular data (nuclear ribosomal DNA) to place the new taxa in a phylogenetic context.

An integrative approach assesses the intraspecific variations of Procamallanus (Spirocamallanus) inopinatus, a common parasite in Neotropical freshwater fishes, and the phylogenetic patterns of Camallanidae.

Integrative taxonomy was used to evaluate two component populations of Procamallanus (Spirocamallanus) inopinatus in Brazil and the phylogeny Camallanidae. Parasite populations were collected in the characiform Anostomoides passionis from River Xingu (Amazon basin) and Megaleporinus elongatus from River Miranda (Paraguay basin). Morphology was analysed using light and scanning electron microscopy (SEM). Genetic characterization was based on partial sequences of the 18S and 28S rDNA, and COI mtDNA. Phylogenies were based on 18S and COI due to data availability. Generalized Mixed Yule Coalescent (GMYC), Poisson Tree Process (PTP) and *BEAST were used for species delimitation and validation. SEM revealed for the first time the presence of minute denticles and pore-like structures surrounding the oral opening, phasmids in females and confirmed other important morphological aspects. Statistical comparison between the two-component populations indicated morphometric variations, especially among males. The different component population of P. (S.) inopinatus showed variable morphometry, but uniform morphology and were validated as conspecific by the GMYC, PTP and *BEAST. Some camallanid sequences in GenBank have incorrect taxonomic labelling. Host, environment and geographic aspects seem to be related to some lineages within Camallanidae; however, their real phylogenetic meanings are still unclear.

A New Species of Triumphalisnema (Nematoda: Coronostomatoidea) Parasite of Proculejus hirtus (Coleoptera: Passalidae) from Mexico, and the Position of the Family in the Oxyuridomorpha.

A new species of the nematode Triumphalisnema Kloss, 1962 (Oxyuridomorpha), is described from the wood beetle Proculejus hirtus Truqui from the mountain mesophilic forest in Hidalgo State, Mexico. Triumphalisnema zuuei n. sp. is distinguished from the other 4 congeners species by the presence of an expanded cervical ring, well-developed lateral alae, an obtuse cauda with a short and bifurcated caudal appendage, series of cuticular folds at ventral and dorsal body surface from excretory pore level to anal region, and ellipsoidal eggs ornamented with numerous small mushroom-like structures over the surface. The phylogenetic position of the new species is inferred based on a Maximum Likelihood and Bayesian Inference analysis of partial sequences of 18S SSU rRNA. The phylogenetic analysis showed that Triumphalisnema zuuei n. sp., the only representative of the Traklosiidae in our study, is closely related to Coynema poeyi and species of Longior, Hystrignathus, and Lepidonema, all of them members of Hystrignathidae. These relationships are supported by high support values. The present study increases to 5 the number of species assigned to Triumphalisnema, all of them parasites of Passalidae. Additionally, a taxonomic key to the species of the genus is provided.

Life Cycle of the Trout Cecal Nematode, Truttaedacnitis truttae (Nematoda: Cucullanidae): Experimental and Field Observations.

Truttaedacnitis truttae is a cucullanid nematode of primarily salmonine fishes. Brown trout (Salmo trutta) in Europe reportedly become parasitized by ingesting lampreys (Lampetra planeri) carrying infective larvae. However, our field and laboratory observations suggested that North American specimens of T. truttae have an alternative life cycle. High abundances and potential impact of T. truttae in rainbow trout, Oncorhynchus mykiss, in the Colorado River drainage in Grand Canyon, where there are no lampreys, prompted a study on the transmission dynamics of this nematode. Eggs of T. truttae, collected from live gravid females, were incubated in the laboratory. Snails, Physa gyrina and Lymnaea sp., were exposed to T. truttae larvae 3-4 wk later. Active larvae of T. truttae were observed penetrating the intestinal wall of exposed snails, and worm larvae were found in the visceral tissues when examined 1 wk after exposure. Larvae in snails showed little growth and development 2 wk later and corresponded to L3 larvae. Infected snails were fed to hatchery-reared juvenile rainbow trout. Developing stages were subsequently found in the mucosal lining and lumen of trout intestines. Adult male and female (gravid) worms were found in the ceca of trout examined 5-6 mo after consuming infected snails. Larvae found in pepsin/trypsin digests and mucosal scrapings from wild, naturally infected, trout corroborate laboratory findings. Screening of Physa sp. and gammarids collected from Colorado River, Grand Canyon, for natural infections with T. truttae using the ITS1 rDNA marker gave positive results. Truttaedacnitis truttae is the second species, after Truttaedacnitis clitellarius of lake sturgeon, capable of using a snail first intermediate/paratenic host and is similar to several other cucullanids in having a histotropic phase of development in the definitive fish host.

Redescription of Dichelyne ( Cucullanellus) Dichelyneformis (Nematoda: Cucullanidae) and Description of a New Congeneric Species in Eleginops maclovinus (Pisces: Eleginopsidae) Collected in the Bay of Corral, Chile.

Dichelyne ( Cucullanellus) dichelyneformis ( Szidat, 1950 ) Petter, 1974 , was collected in the intestine of the rock cod, Eleginops maclovinus, in the Bay of Corral, Chile, and redescribed based on light and scanning electron microscopy. The correct arrangement of caudal papillae and post deirids, the shape of gubernaculum, and the morphology and number of denticles surrounding the oral opening are described for the first time. These characteristics along with the excretory pore position, size of spicules, and presence of a nodular thickening near the distal end of the spicules differentiate D. ( C.) dichelyneformis from the other congeners reported in South America and in the Antarctic. The new congeneric species found in E. maclovinus differs from D. ( C.) dichelyneformis based on the larger males, larger and more numerous denticles with a smooth surface, weakly developed sclerotized plates in esophastome, excretory pore and deirids posterior to nerve ring, shorter gubernaculum and spicules with no thickening on their distal region, lower spicules/body length ratio (10.4-15.1%), and a papilla-like phasmids closer to pairs 8 and 10.

Cosmocerca bengalensis sp. nov. (Nematoda: Cosmocercidae) in Hoplobatrachus tigerinus (Daudin, 1803) (Amphibia, Anura, Dicroglossidae) from West Bengal, India.

Cosmocerca bengalensis sp. nov. (Ascaridida, Cosmocercidae) recovered from the rectum of an Indian bullfrog, Hoplobatrachus tigerinus (Daudin, 1803), collected from Hetampur town in Birbhum district of West Bengal, India, is described and illustrated. This species is similar to C. acanthurum, C. banyulensis, C. cruzi, C. japonica, C. kalesari, C. microhylae, C. novaeguineae, C. ornata, C. paraguayensis, C. parva, C. podicipinus and C. travassosi in having 5 pairs of plectanes supporting preanal papillae but differs from these species by general morphometry, absence of somatic papillae in females, absence of gubernaculum and having only one pair of adanal papillae in males and one pair postanal papillae in females except C. microhylae. Present parasites differ from C. microhylae by absence of gubernaculum and general morphometry. Cosmocerca bengalensis sp. nov. represents the thirtheith species assigned to the genus, seventh from Oriental region and fifth species from India.

Redescription of Dichelyne (Cucullanellus) jialaris (Nematoda: Cucullanidae), a parasite of seabreams (Perciformes: Sparidae) in East Asia.

An insufficiently known nematode species Dichelyne (Cucullanellus) jialaris Luo, Guo, Fang et Huang, 2004 (Cucullanidae), originally described from the red seabream Pagrus major (Temminck et Schlegel) (Sparidae) in the Taiwan Strait, off China, is redescribed based on light and scanning electron microscopical (SEM) examinations of specimens collected from the intestine of three species of sparid fishes, Acanthopagrus schlegelii (Bleeker), Evynnis tumifrons (Temminck et Schlegel) and P. major, in Hiroshima Bay, Japan. The present redescription provides exact data on the cephalic structure, character of cephalic papillae and amphids, location of the excretory pore, deirids and phasmids, and the number and distribution of caudal papillae in the male; the presence of the dorsal postdeirid in this species is reported for the first time. The SEM study revealed that the anterior cloacal lip has a median lobe-like elevation bearing two minute papillae, whereas the posterior cloacal lip is somewhat depressed, with a median longitudinal rod-like elevation probably serving to direct the movement of spicules. The size of eggs is reported for the first time. Dichelyne (C.) jialaris differs from the morphologically similar D. (C.) pleuronectidis (Yamaguti, 1935) mainly in the shape of the oesophagus. The present finding of D. (C.) jialaris represents the first record of this nematode from fishes in Japanese waters and A. schlegelii and E. tumifrons are its new host records.

New Species of Falcaustra (Nematoda: Kathlaniidae) in Batagur trivittata (Testudines: Geoemydidae) from Myanmar.

Falcaustra tintlwini sp. nov. (Ascaridida, Kathlaniidae) from the large intestine of Batagur trivittata (Testudines, Geoemydidae) is described and illustrated. Falcaustra tintlwini represents the 20th Oriental species assigned to the genus and is distinguished from other Oriental species by the distribution pattern of the caudal papillae (6 precloacal, 12 postcloacal, and 1 median), length of spicules (0.43-0.50 mm) and absence of a pseudosucker.

Description of a new species Physaloptera goytaca n. sp. (Nematoda, Physalopteridae) from Cerradomys goytaca Tavares, Pessôa & Gonçalves, 2011 (Rodentia, Cricetidae) from Brazil.

Nematodes of the genus Physaloptera are common in rodents, including in species of the Family Cricetidae. There is no report of nematodes parasitizing Cerradomys goytaca, so this is the first one. For this study, 16 rodents were captured in the city of Quissamã, in the northern of Rio de Janeiro State. The rodents were necropsied, and the digestive tracts were analyzed under a stereomicroscope for the presence of parasites. The nematodes were fixed in hot AFA, clarified in Amann's lactophenol, mounted on slides with coverslip, and observed under an optical microscope. Part of the nematodes was fixed in Karnovisk solution for scanning electron microscopy. Nematodes presented evident sexual dimorphism. Oral openings had two semicircular pseudolabia, with an external lateral tooth and an internal lateral tripartite tooth on each pseudolabium. Males had a ventral spiral curved posterior ends with the presence of a caudal alae with 21 papillae with four pairs of pedunculated papillae arranged laterally, three pre-cloacal sessile papillae arranged rectilinearly and five pairs of post-cloacal sessile papillae. There was also a pair of phasmids located between the fourth and fifth pairs of post-cloacal papillae as well as two spicules that were sub-equal in size but of distinct shapes. The females have five uterine branches. The morphological and morphometrical analyses of the nematodes collected from C. goytaca were compared with other species, and the results indicated that this is a new species of the genus Physaloptera, Physaloptera goytaca n. sp.

Phylogenetic Relationships of Spiruromorph Nematodes (Spirurina: Spiruromorpha) In North American Freshwater Fishes.

Nematodes are common in the parasite communities of North American freshwater fishes, and the majority of them belong to 1 conventional order, Spirurida Chitwood, 1933. Within the Spirurida, the superfamilies Habronematoidea Chitwood and Wehr, 1932 and Thelazioidea Sobolev, 1949 have undergone considerable diversification. The dominant families of these 2 superfamilies, Cystidicolidae Skrjabin 1946 and Rhabdochonidae Railliet, 1916, respectively, are particularly common, widely distributed, and diverse, especially in North America, yet their phylogenetic relationships remain largely unexplored. In this study, we use near complete sequences of the 18S rRNA genes ( SSU rDNA) from species in 6 genera ( Capillospirura Skrjabin, 1924, Cystidicola Fischer, 1798, Salmonema Moravec, Santos and Brasil-Sato, 2008, Rhabdochona Railliet, 1916, Spinitectus Fourment, 1883, and a putative new cystidicolid in mooneyes, Hiodontidae), along with a species of Hedruris Nitzsch, 1812 from newts as a surrogate for the fish parasite Hedruris tiara VanCleave and Mueller, 1932, to explore their phylogenetic relationships. These sequences, together with available sequences from a range of other nematodes, including fish nematodes in other groups (Camallanoidea and 'Seuratoidea'), were analyzed using Bayesian inference and maximum likelihood. The results from both analyses indicate, for the first time, support for the close relationships of the sturgeon parasite Capillospirura with Ascarophis van Beneden, 1871 and Cystidicola; the relationship of the cystidicolid from Hiodontidae with Salmonema of salmonid fishes; the monophyly of the 2 dominant spiruridan genera of fishes, Rhabdochona and Spinitectus; and for previous relationships among Nearctic Spinitectus spp. The results also indicate a closer relationship of Rhabdochona and Spinitectus than is suggested by their conventional classification and reject the monophyly of Habronematoidea, Thelazioidea, and Cystidicolidae. Hedruridae appears to be an early branching lineage of spirurins. Finally, the pattern of association between the fish parasites in this study and their hosts indicates, with few exceptions, ecologically driven diversification events involving host shifting not related to the phylogenetic relationships of their hosts.

Morphological and genetic characterization of Pterygodermatites (Paucipectines) zygodontomis (Nematoda: Rictulariidae) from Necromys lasiurus (Rodentia: Sigmodontinae) from Uberlândia, Brazil.

Pterygodermatites (Paucipectines) zygodontomis, a nematode parasite of the small intestine of the rodent Necromys lasiurus, from Uberlândia, Minas Gerais state, Brazil, was analysed by light and scanning electron microscopy. Additionally, phylogenies were inferred from the mitochondrially encoded cytochrome c oxidase I gene (MT-CO1). Details of the helminth surface, such as the oral aperture, cephalic papillae, papillae in the posterior region of the body and longitudinal cuticular elements represented by spine-like projections and fans are presented, adding new taxonomic details. Molecular phylogenetic analysis, based on the MT-CO1, demonstrated that P. (P.) zygodontomis and Pterygodermatites (Paucipectines) jaegerskioldi form a unique evolutionary unit in accordance with the subgenus Paucipectines and corroborated their occurrence in cricetid and didelphid hosts.

A New Rictulariid (Nematoda: Spirurida) in Xenarthrans from Argentina and New Morphological Data of Pterygodermatites ( Paucipectines) Chaetophracti.

Pterygodermatites is a cosmopolitan genus of nematodes from mammals, and it is frequently encountered in the parasite fauna of armadillos (Mammalia, Xenarthra, Cingulata). In this work, a new species, Pterygodermatites ( Paucipectines) argentinensis, is described, and new morphometric data, new host records, and the geographical distribution of Pterygodermatites ( Paucipectines) chaetophracti are provided. We examined 109 hosts belonging to Chaetophractus vellerosus, Chaetophractus villosus, Cabassous chacoensis, Dasypus hybridus, Tolypeutes matacus, and Zaedyus pichiy, from several regions of Argentina. Pterygodermatites ( Paucipectines) argentinensis can be distinguished from P. ( P.) chaetophracti by the morphology and size of esophageal teeth of both sexes, by subequal and longer spicules, by having only 1 precloacal cuticular semicircular fan in males, and by a greater number of cuticular processes in females. Cabassous chacoensis and Zaedyus pichiy are new hosts for Pterygodermatites ( P.) chaetophracti.

Morphological and molecular characterisation of Heliconema hainanensis sp. nov. (Spirurina: Physalopteridae) from congers in the South China Sea, with a key to the species of Heliconema.

Heliconema hainanensis sp. nov. collected from Uroconger lepturus (Richardson) (Anguilliformes: Congridae), Muraenesox cinereus (Forsskål) and Congresox talabonoides (Bleeker) (Anguilliformes: Muraenesocidae) in the South China Sea was described using light and scanning electron microscopy. The new species differs from its congeners by the following morphology: pseudolabia, the number and arrangement of caudal papillae (4 pairs of pedunculate precloacal papillae arranged in 2 groups of 2 and 2 pairs and 6 pairs of pedunculate postcloacal papillae arranged in 4 groups of 1, 2, 1 and 2 pairs), the length of spicules [left spicule 0.51-0.69 mm, right spicule 0.20-0.27 mm, spicule (right:left) ratio 1:2.20-2.69] and the morphology of the female tail tip. In addition, specimens of the new species collected from the three different hosts and specimens of an unidentified species of Heliconema collected from U. lepturus were characterised using molecular methods by sequencing the internal transcribed spacer (ITS) of ribosomal DNA. Analyses and comparison of the ITS sequence of H. hainanensis sp. nov. with Heliconema sp. support the validity of the new species based on morphological observations. An identification key to the species of Heliconema is also provided.

Morphological and molecular characterisation of Heliconema hainanensis sp. nov. (Spirurina: Physalopteridae) from congers in the South China Sea, with a key to the species of Heliconema

Heliconema hainanensis sp. nov. collected from Uroconger lepturus (Richardson) (Anguilliformes: Congridae), Muraenesox cinereus (Forsskål) and Congresox talabonoides (Bleeker) (Anguilliformes: Muraenesocidae) in the South China Sea was described using light and scanning electron microscopy. The new species differs from its congeners by the following morphology: pseudolabia, the number and arrangement of caudal papillae (4 pairs of pedunculate precloacal papillae arranged in 2 groups of 2 and 2 pairs and 6 pairs of pedunculate postcloacal papillae arranged in 4 groups of 1, 2, 1 and 2 pairs), the length of spicules [left spicule 0.51-0.69 mm, right spicule 0.20-0.27 mm, spicule (right:left) ratio 1:2.20-2.69] and the morphology of the female tail tip. In addition, specimens of the new species collected from the three different hosts and specimens of an unidentified species of Heliconema collected from U. lepturus were characterised using molecular methods by sequencing the internal transcribed spacer (ITS) of ribosomal DNA. Analyses and comparison of the ITS sequence of H. hainanensis sp. nov. with Heliconema sp. support the validity of the new species based on morphological observations. An identification key to the species of Heliconema is also provided.

A new species of the genus Spiroxys (Nematoda: Gnathostomatidae) from Madagascan pleurodiran turtles (Pelomedusidae).

Spiroxys ankarafantsika, sp. nov. is described from Madagascar in two species of freshwater turtles, Pelusios castanoides and Pelomedusa subrufa. Spiroxys ankarafantsika differs from other species of the genus in having pseudolabial teeth only on the median lobes and no other cuticular prominences, a smooth cuticular collar, deirides as cervical minute spine-like projections, and a gubernaculum without tubes. This is the first record of a nominal species of the genus Spiroxys from the Ethiopian region.