Review of Admirandus Belogurov & Belogurova, 1979 (Nematoda, Oncholaimidae) with the description of a new species and the first record of the genus from Brazil.

The present study provides a description of a new Admirandus species from northeastern Brazil, together with an updated species identification key. Admirandus capibaribei sp. n. can be distinguished from all the other Admirandus species by its physical dimensions (body length, a, stoma and spicule ratios), sexual dimorphism of the tail, the absence of pre-cloacal supplements, and the presence of a row of denticles at the base of the right ventrosublateral tooth. While Admirandus has been reported from temperate, subtropical and tropical environments around the world, this is the first record of the genus from Brazil. Further research on Admirandus and other Adoncholaiminae species, which include the integration of morphological and molecular approaches, will be important to provide a better understanding of the taxonomy of this group, as well as on its demanian system.

Six new species of free-living nematodes (Nematoda: Enoplida) from deep-sea cold seeps on Hikurangi Margin, New Zealand.

Little is known about the taxonomy of deep-sea nematode species inhabiting cold seep habitats. An opportunity to characterize the nematode species communities of New Zealand cold seeps was provided by a 2019 research voyage to New Zealand's Hikurangi Margin, during which macrofauna cores were obtained at two seeps at approximately 1,250 and 2,000 m water depth. Here, six new species of the orderEnoplida are described. Metacylicolaimus catherinae sp. nov. represents the first record of the genus for the New Zealand Exclusive Economic Zone and for the deep sea globally. Halalaimus talaurinus sp. nov., Thalassoalaimus duoporus sp. nov. and Crenopharynx crassipapilla sp. nov. are only the second species of their respective genera to be described/recorded from New Zealand waters, and Oncholaimus adustus sp. nov. is the eighth species of the genus to be recorded from the region. Rhabdodemania zealandiaensis sp. nov. was among the most abundant and widespread species found at the Hikurangi Margin seep sites. A few specimens had been found in a previous ecological study of meiofaunal nematode communities on Chatham Rise, a submarine ridge south of Hikurangi Margin. It is possible that this species has a preference for seep environments due to elevated food availability, however it does not seem to be exclusively found in seeps. We find no evidence for an affinity between nematode seep communities in New Zealand and elsewhere, which is consistent with the high variability in nematode community observed to date among regions. Ongoing work on the ecology and distribution of nematode communities at the Hikurangi Margin seep sites will help determine spatial patterns in abundance and species distributions in more detail, including the identification of any species/taxa with affinities with seeps.

Taxonomic review of Thoracostomopsidae (Nematoda, Enoplida): state of the art, list of valid species and dichotomous keys.

Thoracostomopsidae is a family of free-living marine nematodes that has three subfamilies (Thoracostomopsinae, Trileptiinae and Enoplolaiminae). Most species descriptions within this family are very old and lack indication of important morphological details, so this article aims to fill this gap in the literature. This taxonomic review provides a list of all valid species, as well as species inquirenda, nomina nuda and synonyms, for each genus. Our review recognizes 16 valid genera, 193 valid species, 47 species inquirendae and three species as nomen nudum. Additionally, taxonomic dichotomous keys were constructed, modified or updated for each genus, as well to the subfamilies, using the most important diagnostic characters.

Description of two new species of Nematoda: Litinium macramphida sp. nov. (Oxystominidae) and Cyartonema breviseta sp. nov. (Cyartonematidae) from the Yellow Sea, China.

Two new species of Nematoda, Litinium macramphida sp. nov. and Cyartonema breviseta sp. nov. are described from the Yelllow Sea. Litinium macramphida sp. nov. is characterized by body relatively long, inner and outer labial sensilla setiform with same length, amphideal fovea large and drop-shaped with amphideal aperture ovoid, spicules short and wide, gubernaculum simple and boat shaped, two precloacal supplements, and tail conical with rounded tip. Cyartonema breviseta sp. nov. is characterized by body short and slender, four cephalic sensilla papilliform, amphideal fovea circular and large, spicules curved and sickle-shaped, gubernaculum with dorsal-caudal apophysis and posterior end anteriorly hooked, and tail conical.

New genus of Ironidae (Nematoda, Enoplida) from Piip volcano (the Bering Sea).

Piipironus grandis gen. et sp. nov. is described from Piip submarine volcano, the Bering Sea. Piipironus gen. nov. shows all main characters of Thalassironinae but differs from all known ironids in the form of the amphid (spiral vs pocket-like) and the simultaneous presence of precloacal papilliform supplements and tubular postcloacal organs. Pared tubular postcloacal organs have never been described before for the family Ironidae. The combination of papilliform precloacal supplements and the pair of tubular postcloacal organs described for Piipironus grandis gen. et sp. nov. is unique among nematodes. The study of the nematofauna of the Piip submarine volcano began quite recently, and Piipironus is the second new genus of nematodes described from here from one sample of bottom sediments. This can be taken as one of the examples of the hyper-high diversity of marine nematodes.

Two new species, Parabathylaimus gracilis sp. nov. and Belbolla sinica sp. nov. (Nematoda: Enoplida), from Yangma Island of the Yellow Sea, China.

Two new species Parabathylaimus gracilis sp. nov. and Belbolla sinica sp. nov. are described from Yangma Island, Yellow Sea. Parabathylaimus gracilis sp. nov. is characterized by six outer labial setae three-jointed, inner labial setae and cephalic setae unjointed, amphidial fovea unispiral with circular aperture and positioned at middle of buccal cavity, spicules paired and slightly curved, gubernaculum kidney-like and distal end heavily cuticularized with a pointed projection, tail conical without long subterminal setae. Belbolla sinica sp. nov. is characterized by short body length, posterior pharynx region with seven bulbs, spicules straight with proximal and distal end tapered and middle part thickened, gubernaculum short without apophysis, two small wing-shaped precloacal supplements well developed, tail conico-cylindrical with cylindrical portion short.

Two new species of Enoplolaiminae (Enoplida: Thoracostomopsidae) from Ro Negro and Chubut, Argentina.

Two new species of free-living marine nematodes of the subfamily Enoplolaiminae are described from Ro Negro and Chubut Provinces, Argentina. Enoplolaimus variispiculum sp. n. is characterized by having asymmetric spicules, different in size and distal tips. It is the only species with this characteristic in the whole genus. Mesacanthoides flagellatum sp. n. is characterized by mandibles texture, weakly cuticularized and mottled and mandibular plates with pronounced v shaped incision posterior to the anterior bar. Cephalic capsule wider than long with setae on posterior end, males with long spicules, complex gubernaculum and flagellate tail.

Capillaria hepatica (syn. Calodium hepaticum) as a Cause of Asymptomatic Liver Mass.

Capillaria hepatica (syn. Calodium hepaticum) is a parasitic nematode of rodents, rarely infecting humans. An asymptomatic Israeli adult male with extensive travel history was diagnosed with a liver mass on routine post-thymectomy follow-up. Imaging and computer tomography (CT) guided biopsy were inconclusive. Surgical excision revealed an eosinophilic granuloma with fragments of a nematode suspected to be C. hepatica. Molecular methods verified the diagnosis, and the patient was treated empirically. This is the first case of hepatic capillariasis described in Israel, and the first to be diagnosed using molecular methods.

Oloncholaimus piipi gen. et sp. nov. (Nematoda, Oncholaimidae) from Piip submarine volcano, the Bering Sea.

Oloncholaimus piipi gen. et sp. nov. is described from Piip submarine volcano, the Bering Sea. Oloncholaimus gen. nov. shows all main characters of Oncholaiminae: females monodelphic-prodelphic with antidromously reflexed ovary, three teeth with left ventrosublateral the largest, oncholaimoid type of Demanian system. New genus can be differentiated from all other genera of the family Oncholaimidae by the complex shape of dorsal and right ventrosublateral teeth with apical antler-shaped extension. Oloncholaimus piipi sp. nov. has large body (5960-7045 µm), six outer labial and four cephalic setae equal in size (5-7 µm), equal spicules (110-131 µm long) without gubernaculum, and complex precloacal supplementary organ composed of 8-9 cylindrical processes.

Three new species of free-living marine nematodes (Nematoda: Enoplida) from the Clarion-Clipperton Fracture Zone (CCFZ), North Pacific.

Three new species of free-living marine nematodes, Phanodermopsis dordi sp. nov., Halalaimus shinkai sp. nov., and Oxystomina hakureiae sp. nov. are described from the abyssal sediments of the Clarion-Clipperton Fracture Zone, North Pacific. Phanodermopsis dordi sp. nov. differs from the congeners by having papilliform anterior sensilla and a long conical tail with an acute tip. Halalaimus shinkai sp. nov., belonging to Keppner's group 2 based on the presence of caudal alae and the absence of precloacal sensillum or pore, can be distinguished from all of the members of this group by the presence of lateral pieces of gubernacula. Oxystomina hakureiae sp. nov. differs from the congeners by the short setiform anterior sensilla, the amphid located posterior to cephalic sensilla, the conico-cylindrical tail in both sexes, the spicules with a velum and a capitulum, the presence of the gubernacula and the precloacal setae, and the diorchic and monodelphic reproductive systems. The amended dichotomous keys to the species of Phanodermopsis, Halalaimus group 2, and Oxystomina are provided. A new combination Nemanema arenaria (Bussau, 1990) comb. nov. transferred from Oxystomina is also provided.

New species of Thoonchus (Enoplida, Enchelidiidae) from the Yellow Sea and redescription of T. giganticus Belogurova et al., 1986.

The family Enchelidiidae is recovered as monophyletic and appears to be a more recently derived taxon within the superfamily Oncholaimoidea. It combines nematodes with buccal cavity with three unequal teeth, crenate pharynx, and absence of demanian system. Genus Thoonchus was erected for nematodes characterized by the large buccal cavity with heavily cuticularized walls and several rows of denticles, short and arcuate spicules and gubernaculums with expanded corpus. One new species is described here from the Sishili Bay, located in the northern Yellow Sea. Thoonchus covidus sp. nov. is characterized by the body length 3195‒4339 µm, outer labial and cephalic setae in one circle, pocket shaped amphid above the buccal cavity base, secretory-excretory pore at the base of cephalic setae, arched spicules, gubernaculum with thin proximal extension parallel to spicules, preanal supplement absent, three pairs of preanal papillae. It differs from other congeners by the position of secretory-excretory pore, absence of supplementary organ in males and presence of three pairs of precloacal papillae. Redescription of T. giganticus is also provided. After critical evaluation of the genus we recognize 4 valid species and provide a taxonomic key to species.

First report in pre-Columbian mummies from Bolivia of Enterobius vermicularis infection and capillariid eggs: A contribution to Paleoparasitology studies.

OBJECTIVE: This study was designed to search for ancient parasites in abdominal content and coprolites from Bolivian mummies. MATERIALS: Twelve mummified individuals from the Andean highlands, housed at the National Museum of Archaeology (MUNARQ) in La Paz, Bolivia. METHODS: Microscopic analysis of rehydrated samples (coprolites and abdominal content), following Lutz's spontaneous sedimentation technique. RESULTS: Eggs of Enterobius vermicularis were identified in coprolites from one mummy, and capillariid eggs in the organic abdominal content from another individual. CONCLUSIONS: This is the first evidence of ancient intestinal parasites in Bolivian mummies. SIGNIFICANCE: This pioneering study focused on the search of ancient intestinal parasites in human remains of the Bolivian Andes and contributes to greater knowledge of paleoparasitology in South America. LIMITATIONS: All mummies in the MUNARQ belonged to the Andean Bolivian highlands (post-Tiwanaku era or Late Intermediate Period), although the exact provenance of the material and the associated contexts are not well recorded. SUGGESTIONS FOR FURTHER RESEARCH: Considering the great number of well-known archaeological sites and other unexplored sites in Bolivia, in addition to large collections in museums, further paleopathological and paleoparasitological molecular studies in mummies and skeletons are called for.

A new species of Cephalanticoma (Enoplida: Anticomidae) from Brazilian coast (Atlantic Ocean), with emended diagnosis and dichotomous key to the genus.

A new species of the genus Cephalanticoma is described for the Atlantic Ocean in the Potiguar Basin off the continental shelf of northeast Brazil. Cephalanticoma rugatusa sp. n. is characterized by bearing head capsule ending on the level of amphideal fovea, a tubular precloacal supplement and two rows of thin precloacal setae. Cephalanticoma rugatusa sp. n. differs from all other species of the genus by having a precloacal cuticular papilla in front of the cloaca and a cuticular transversal wrinkle which extends from the papilla elevation to the conical-cylindrical portion of the tail occupying both subventral regions. An emended diagnosis and a dichotomous key to species based on both genders are provided.

Wieseria bicepes sp. nov. (Nematoda: Oxystominidae) from the South China Sea.

One unrecorded species of free-living marine nematodes from the South China Sea is described as Wieseria bicepes sp. nov. The present species is characterized by three circles of anterior sensilla nearly equal in length; four cephalic setae just behind the outer labial setae; oblong amphideal fovea with double contours and a handle-like protrusion at the base; tail tip bifurcate; spicules slightly curved with proximally cephalated and distally tapered; gubernaculum absent. The species is easily distinguished from the congeneric species by tail with a bifurcate tip and cephalic setae closely adjacent to labial setae.

Three new species of the free-living marine nematode Metoncholaimus Filipjev, 1918 (Enoplida, Oncholaimidae) from Argentinean coasts.

Three new species of free-living marine nematodes of the genus Metoncholaimus are described from San Matías gulf (Río Negro, Argentina). Metoncholaimus sanmatiensis sp. n. is characterized by large body size, long spicules, small gubernaculum, presence of long setose pre- and postcloacal genital sensilla and presence of precloacal pores. Metoncholaimus perdisus sp. n. is characterized by small-sized body, short spicules, small gubernaculum, presence of long setose pre- and postcloacal genital sensilla and presence of pre- and postcloacal pores. Metoncholaimus paracavatus sp. n. is closely related to Oncholaimus cavatus but can be considered as a new Metoncholaimus species based on the presence of gubernaculum and the morphology of the demanian system. A compendium of all valid species, including new species, is given.

A new species of the genus Thalassironus (Nematoda: Enoplida: Ironidae) from the coasts of South Korea.

A new species of the genus Thalassironus de Man, 1889 was discovered during several surveys of the offshore marine ecosystem in Korea. This new species belonging to the family Ironidae, Thalassironus koreanus sp. nov., shares general morphological traits of the genus such as an optically smooth cuticle, buccal cavity consisting of two parts with three movable teeth and thick cuticularized walls, six rounded lips with ten cephalic setae, slit-like amphid and short conical tail with caudal glands present. The new species is most closely related to T. bohaiensis, first discovered in the Bohai Sea, in terms of body ratio (a, b, c, c') and general morphology, but differs by its generally longer and larger body structures, cervical setae at the level of the buccal cavity, paired somatic setae distributed along the body, and longer/larger spicule. A description of Thalassironus koreanus sp. nov., diagnosis of the genus, emended pictorial key for the genus and discussion of important characteristics for the genus is provided.

Thalassironus filiformis sp. nov. (Nematoda, Enoplida) from the South China Sea.

A new species of the genus Thalassironus de Man, 1889, which was discovered from marine sediments in the South China Sea, is described here as Thalassironus filiformis sp. nov. The new species is characterized by having short outer labial setae and cephalic setae of equal length, long filiform tail, buccal cavity with three anterior teeth and three additional teeth just posterior to amphideal fovea, male with a segmented midventral precloacal seta, spicules double curved, slender with ventral ala. It is very similar to Thalassironus lynnae Keppner, 1987, but can be differentiated from the latter species by much shorter cephalic setae (8 µm vs 14-16 µm), longer tail (772-780 µm vs 300-506 µm), longer spicules (67-68 µm vs 35-40 µm), smaller value of de Man ratio "a" (66 vs 99.7-102) and different structure of spicules. An updated dichotomous key to all known species of Thalassironus is provided.

Two new and one known species of Phanodermatidae (Nematoda: Enoplida) from Sagami Bay, Japan.

Two new and one known species of free-living marine nematode belonging to the family Phanodermatidae are described. They were collected during the 12th Japanese Association for Marine Biology (JAMBIO) Coastal Organism Joint Survey off Jogashima, Japan in Sagami Bay, North Pacific Ocean. Phanodermopsis kohtsukai sp. nov. differs from the congeners by the shape of the tail, the longer spicules, and the absence of the gubernaculum. Micoletzkyia nakanoi sp. nov. differs from the congeners by the absence of a circle of cervical setae, the proportion of the tail, the cylindrical gubernaculum without projection, and the position of the vulva. Crenopharynx caudata (Filipjev, 1927) comb. nov. is transferred from the genus Phanodermopsis based on the presence of the long spicules. The morphological characters of the newly collected specimens of C. caudata comb. nov. are in excellent agreement with those shown in the original description of the specimens from Arctic Russia and the previous redescription of the specimens from Skagerrak. The new diagnoses and species lists for these three genera and two dichotomous keys to the males of Micoletzkyia and Crenopharynx are provided.

Further evaluation of the efficacy of emamectin benzoate for treating Pseudocapillaria tomentosa (Dujardin 1843) in zebrafish Danio rerio (Hamilton 1822).

Pseudocapillaria tomentosa is a pathogenic nematode parasite, causing emaciation and severe inflammatory lesions in the intestines in zebrafish Danio rerio (Hamilton 1822). Emamectin benzoate is commercially available analogue of ivermectin used for treating salmon for sea lice, under the brand name SLICE® , and we have used this for treating zebrafish with the P. tomentosa. Here, SLICE® , 0.2 per cent active emamectin benzoate, was used for oral treatments at 0.35 mg emamectin benzoate/kg fish/day for 14 days starting at 7 days post-exposure (dpe). Another experiment entailed initiating treatment during clinical disease (starting at 28 dpe). Early treatment was very effective, but delaying treatment was less so, presumably due to inappetence in clinically affected fish. We evaluated emamectin benzoate delivered in water, using Lice-Solve™ (mectinsol; 1.4% active emamectin benzoate) in two experiments. Application of four 24-hr treatments, space over 7 days was initiated at 28 dpe at either 0.168 or 0.56 mg emamectin benzoate/L/bath, and both treatments completely eradicated infections. This was 3 or 10 times manufacture's recommended dose, but was not associated with clinical or histological side effects.