Morphological and molecular characterization of two new species of the genus Aporcelinus Andrássy, 2009 (Nematoda, Dorylaimida, Aporcelaimidae) from the USA, with new insights on the phylogeny of the genus.

Two new species of the genus Aporcelinus from the USA are described and illustrated. Aporcelinus floridensis sp. n. is characterized by its 1.12-1.52 mm long body, lip region offset by marked constriction and 14.5-17.0 µm broad with perioral liplets, odontostyle 16.5-20.0 µm at its ventral side and 1.1-1.2 times the lip region diameter, neck 316-395 µm long, pharyngeal expansion occupying 43-48% of total neck length, uterus simple and 33-56 µm long or 0.8-1.2 times the corresponding body diameter, V = 48-54, female tail conical (36-49 µm long, c = 27-41, c' = 1.2-2.0) with finely rounded terminus and no hyaline portion, and male absent. Aporcelinus paolae sp. n. is characterized by its 1.29-1.80 mm long body, lip region offset by marked constriction and 14-16 µm broad, odontostyle 15-17 µm at its ventral side and 1.0-1.1 times the lip region diameter, neck 314-397 µm long, pharyngeal expansion occupying 43-53% of total neck length, uterus tripartite and 128-164 µm long or 2.6-3.6 times the corresponding body diameter, V = 53-57, female tail conical (30-39 µm long, c = 40-51, c' = 1.1-1.3) with finely rounded terminus and variably re-curved dorsad, male tail conical (27-36 µm, c = 39-59, c' = 0.9-1.2), ventrally straight and dorsally convex, spicules 48-54 µm long, and 7-9 irregularly spaced ventromedian supplements lacking hiatus. The analyses of the D2-D3 expansion segments of 28S rRNA (LSU) gene sequences of the two new species confirmed the monophyly of the genus, based upon currently available data, showing a close relationship between the genera Aporcelinus and Makatinus, and justified the placement of Aporcelaimellus, Makatinus and Aporcelinus under the subfamily Aporcelaimellinae.

Morphological and genetic identification of Anisakis paggiae (Nematoda: Anisakidae) in dwarf sperm whale Kogia sima from Brazilian waters.

Anisakid nematodes have been identified in a wide variety of fish and marine mammal species. In Brazil, Anisakis physeteris, A. insignis, A. typica, A. nascetti, and those of the A. simplex complex have been reported infecting fishes and cetaceans. In this study, specimens collected from a dwarf sperm whale Kogia sima (Owen, 1866) stranded on the northeastern coast of Brazil were identified through morphological and genetic analyses as A. paggiae. Anisakids were examined through differential interference contrast light and scanning electron microscopy (SEM). Morphological and morphometric analysis revealed that these specimens belonged to Anisakis sp. clade II and more specifically to A. paggiae, exhibiting a violin-shaped ventriculus and 3 denticulate caudal plates, which are taxonomic characters considered unique to this species. Genetic analysis based on the mtDNA cox2 gene confirmed our identification of A. paggiae. Phylogenetic trees using both maximum likelihood and neighbor-joining methods revealed a strongly supported monophyletic clade (bootstrap support = 100%) with all available A. paggiae sequences. Integrative taxonomic analysis allowed the identification of A. paggiae for the first time in Brazilian waters, providing new data about their geographical distribution. Moreover, here we present the first SEM images of this species.

Philometra mirabilis sp. n. (Nematoda: Philometridae), a new gonad-infecting parasite from the freshwater fish Cichla mirianae (Cichlidae) in Brazilian Amazon.

A new nematode species, Philometra mirabilis sp. n. (Philometridae), is described based on a subgravid female specimen recovered from the ovary of the freshwater perciform fish Cichla mirianae Kullander and Ferreira (Cichlidae) in the Juruena River (Amazon River basin), State of Mato Grosso, Brazil. The new species is morphologically very different from congeners parasitizing fishes in South America, being mainly characterized by the markedly elongate, narrow body 171 mm long (maximum width/body length 1:598), the presence of three small cone-shaped oesophageal teeth protruding out of the mouth and an onion-shaped oesophageal inflation distinctly separated from the posterior part of the oesophagus, the relative length of the oesophagus, and the rounded posterior end of the body without any caudal projections. It is the third known valid species of Philometra Costa, 1845 parasitizing a freshwater fish in South America and the second species of this genus reported from fishes of the family Cichlidae.

Cucullanus egyptae sp. nov. (Nematoda, Cucullanidae) infecting the European eel Anguilla anguilla in Egypt. Morphological and molecular phylogenetic studies.

A total of 80 specimens of the European eel Anguilla anguilla were collected during the period from February 2013 to March 2014 at the coast of the Gulf of Suez (Red Sea, Egypt). A new species of parasitic nematodes was recovered and described as Cucullanus egyptae. It was found in the eel's intestine with a prevalence of 68.7%. The morphology of the recovered parasite was studied by light and scanning electron microscopy. The adult worms had a wide cephalic extremity with a slit-like oral aperture being surrounded by a cuticular ring and delimited internally by a row of small teeth in addition to four sub-median cephalic papillae and one pair of lateral amphids. Body measurements showed that the male worms were smaller than females measuring 7.5-8.9 mm (8.3 ± 0.2) in length and 1.6-1.9 mm (1.8 ± 0.1) in width. Females measured 12.9-13.5 mm (13.1 ± 0.2) in length and 2.9-3.2 mm (3.1 ± 0.1) in width. The posterior end of the males is provided with ten pairs of caudal papillae and two long spicules which are slightly sclerotized, equal in size measuring 0.59-0.65 mm (0.62 ± 0.01) in length. Comparing the present worms with other species of the genus Cucullanus, several similarities were observed. However, peculiar new characteristics such as the precloacal sucker (especially the spicula length), the arrangement and the distribution of the post-cloacal papillae, and the position of the excretory pore make it reasonable to describe a new species. The sequence data of the small subunit (SSU) ribosomal DNA (rDNA) obtained from the present nematode supported its taxonomic position within the genus Cucullanus. The new species is closely related to the first clade of Spirurina and even more closely related to Cucullanus dodsworthi as a sister taxon with a high percentage of identity. The sequence of the recorded SSU rDNA of this parasite is deposited in the GenBank with the accession no. KF681520. It is proposed to name the new species C. egyptae as the first representative of Cucullanidae in Egypt with a new host record.

Huffmanela hamo sp. n. (Nematoda: Trichosomoididae: Huffmanelinae) from the dagger-tooth pike conger Muraenesox cinereus off Japan.

Huffmanela hamo sp. n. is described from eggs only, which were found in black spots in the somatic musculature of a dagger-tooth pike conger, Muraenesox cinereus (Forsskål), caught off Japan. The eggs are 66-77 microm (mean 72 microm) in length and 33-38 microm (mean 35 microm) in width. The surface of the eggs is smooth and bears neither envelope nor filaments. The species is distinguished from other members of the genus by the dimensions of its eggs and the characteristics of their surface. This is the first species of Huffmanela Moravec, 1987 to be described from an anguilliform fish, and the twentieth nominal species in the genus. Similar black spots with eggs were reported four times in ten years from this fish caught off Japan; although eggs could not be examined, it is likely that the same species was involved in all cases.

New host and locality records of two nematode parasites Dujardinnascaris mujibii (Heterocheilidae) and Hysterothylacium aduncum (Anisakidae) from the common seabream Pagrus pagrus: a light and scanning electron microscopic study.

In the present study, the morphology and morphometric characterization of Dujardinnascaris mujibii (Heterocheilidae) and Hysterothylacium aduncum (Anisakidae), new nematode parasites infecting the sea bream Pagrus pagrus (Osteichthyes, Sparidae), were described for the first time from the Gulf of Suez and Hurghada City of the Red Sea, Egypt. Ninety-eight (70 %) and 62 (44.2 %) out of 140 of the examined fish were naturally infected with these nematodes, respectively. The infection was investigated macroscopically by the occurrence of these parasites in the flesh, stomach, intestines, as well as their body cavities as adult and larval stages. D. mujibii is characterized by an elongated body with a length of 36.4 ± 3 (23-38) mm (female) and 20 ± 3.0 (17-24) mm (males); the head is provided with three prominent lips each with four teeth like structures and the apical lip is embossed with a regular zigzag pattern as revealed by SEM. Interlabia were present, with prominent grooves. Juvenile stage is smaller than adults and provided with a spiny mucron. H. aduncum was small, measured 22.5 ± 2.0 (20.0-24.3) mm in length (female) and 16.3 ± 2.0 (14.5-17.4) mm (male). The head region bears three large lips which were clearly separated from each other, with the apical one having two rounded ends and the space between the two adjacent lips occupied by very prominent interlabia. The present study represents new host and locality records from P. pagrus fish in Egypt.

Two new species of Cylicospirura Vevers, 1922 (Nematoda: Spirocercidae) from carnivores in southern Africa, with validation of the related genera Gastronodus Singh, 1934 and Skrjabinocercina Matschulsky, 1952.

Two new species of Cylicospirura Vevers, 1922 are described from carnivores from southern Africa. Cylicospirura crocutae Junker et Mutafchiev sp. n. from Crocuta crocuta (Erxleben) in Zimbabwe is distinguished from its congeners by combinations of characters, including the presence of four cephalic and four external labial papillae, while internal labial papillae were not distinct, the presence of groups of small accessory teeth between the six large tricuspid teeth, the fifth and the sixth pairs of the caudal papillae being equidistant from the cloaca, and a large ratio of length of the muscular oesophagus to that of the glandular oesophagus. Cylicospirura pardalis Junker et Mutafchiev sp. n. from Panthera pardus (Linnaeus) in the Republic of South Africa is characterized by having tricuspid teeth with large, claw-like, abaxial cusps, four cephalic and six internal labial papillae. Based on the number of caudal papillae and the position of the vulva, the subgenera Gastronodus Singh, 1934 and Skrjabinocercina Matschulsky, 1952 are re-elevated to generic rank. Amended diagnoses are proposed for the genera Cylicospirura, Gastronodus and Skrjabinocercina. Petrowospirura lyncis Matschulsky, 1952 is recognized as valid and, together with P. petrowi Sadykhov, 1957 and P. barusi Arya, 1979, is transferred to Cylicospirura as C. lyncis (Matschulsky, 1952) Junker et Mutafchiev comb. n., C. petrowi (Sadykhov, 1957) Junker et Mutafchiev comb. n. and C. barusi (Arya, 1979) Junker et Mutafchiev comb. n., respectively.

Anthelmintic tolerance in free-living and facultative parasitic isolates of Halicephalobus (Panagrolaimidae).

Studies on anthelmintic resistance in equine parasites do not include facultative parasites. Halicephalobus gingivalis is a free-living bacterivorous nematode and a known facultative parasite of horses with a strong indication of some form of tolerance to common anthelmintic drugs. This research presents the results of an in vitro study on the anthelmintic tolerance of several isolates of Halicephalobus to thiabendazole and ivermectin using an adaptation of the Micro-Agar Larval Development Test hereby focusing on egg hatching and larval development. Panagrellus redivivus and Panagrolaimus superbus were included as a positive control. The results generally show that the anthelmintic tolerance of Halicephalobus to both thiabendazole and ivermectin was considerably higher than that of the closely related Panagrolaimidae and, compared to other studies, than that of obligatory equine parasites. Our results further reveal a remarkable trend of increasing tolerance from fully free-living isolates towards horse-associated isolates. In vitro anthelmintic testing with free-living and facultative parasitic nematodes offers the advantage of observing drug effect on the complete life cycle as opposed to obligatory parasites that can only be followed until the third larval stage. We therefore propose Halicephalobus gingivalis as an experimental tool to deepen our understanding of the biology of anthelmintic tolerance.

Description of Rhabdochona (Globochona) rasborae sp. n. (Nematoda: Rhabdochonidae) from the freshwater cyprinid fish Rasbora paviana Tirant in southern Thailand.

A new nematode species, Rhabdochona (Globochona) rasborae sp. n. (Rhabdochonidae), is described from the intestine of the freshwater cyprinid fish (sidestripe rasbora) Rasbora paviana Tirant in the Bangbaimai Subdistrict, Muang District, Surat Thani Province, southern Thailand. It differs from other representatives of the subgenus Globochona Moravec, 1972 which possess eggs provided with lateral swellings in having a spinose formation at the tail tip of both sexes and in some other morphological features, such as the body length of gravid female (8.6-23.7 mm), presence of two-three swellings on the egg, eight anterior prostomal teeth, length ratio of spicules (1:5.3-6.7) and arrangement of male genital papillae. This is the third nominal species of Rhabdochona Railliet, 1916 and the second species of the subgenus Globochona reported from fishes in Thailand. The three species of Rhabdochona recently described from fishes in Pakistan, viz. R. annai Kakar, Bilqees et Khan, 2012, R. bifurcatum [sic] Kakar et Bilqees, 2012, and R. pakistanica Kakar, Bilqees et Khan, 2012, are considered to be species inquirendae.

Collarinema eutriglae n. sp. (Nematoda: Cystidicolidae), a new gastric parasite of the scorpaeniform fish Eutrigla gurnardus (Osteichthyes: Triglidae) in the North Sea, with remarks on the systematic status of Collarinema Sey, 1970.

A new species of parasitic nematode, Collarinema eutriglae n. sp. (Cystidicolidae), is described from the stomach of the marine scorpaeniform fish Eutrigla gurnardus (Linnaeus), the grey gurnard (Triglidae), collected in the North Sea in the vicinity of the Shetland Islands (61°12'N, 00°30'E) during March, 2011. The new species, studied using both light and scanning electron microscopy, is characterised mainly by the structure of the mouth (small pseudolabia with terminal projections, submedian labia and well-developed sublabia not exceeding the labia externally), very small simple deirids, the length of the spicules (405-423 and 117-135 µm) and non-filamented eggs. Collarinema Sey, 1970 is considered a valid genus and an amended diagnosis is provided. Ascarophis collaris Petter, 1970 is transferred to Collarinema as C. collaris (Petter, 1970) n. comb.

Biodiversity and prevalence of parasites of domestic pigeons (Columba livia domestica) in a selected semiarid zone of South Khorasan, Iran.

Five species of nematodes and cestodes were collected from alimentary canals of pigeons: the nematodes were two species: Ascaridia colombae (16.66%) and Hadjelia truncata (1.96%), while the cestodes were Cotugnia digonopora (13.79%), Raillietina magninumida (18.62%) and Raillietina achinobothridia (32.35%); fecal examination revealed: Eimeria spp. (40.19%) and Cryptosporidium oocysts (2.94%); and blood smears showed: Haemoproteus cloumbae (47/05%); in mouth, throat and larynx: Trichomonans gallinae (57.84%); four species of ectoparasites were collected from feathers and subcutaneous nodules as follows: feathers: Pseudolynchia canariensis (63.72%), Columbicola columbae (79.41%), Menopen gallinea (44.11%); subcutaneous nodules: Laminosioptes cysticola (1.96%). From the parasitic fauna identified in this study, it is imperative to institute an integrated parasitic control through constant changing of litter, regular use of antihelminthics, anticoccidials and dusting of birds with pesticides.

Two new species of Rhabdochona (Nematoda: Rhabdochonidae) from freshwater fishes in Thailand.

Two new species ofrhabdochonid nematodes are described from the intestine of freshwater fishes in Chiang Mai Province, northern Thailand: Rhabdochona (Rhabdochona) pseudomysti sp. n. from the catfish Pseudomystus siamensis (Regan) (Bagridae, Siluriformes) in the Fang Brook, a tributary of the Kok River (the Mekong River basin), Fang District and Rhabdochona (Globochona) thaiensis sp. n. from the cyprinid Mystacoleucus marginatus (Valenciennes) (Cyprinidae, Cypriniformes) in the Ping River (the Chao Phraya River basin), Muang District. Rhabdochona pseudomysti is mainly characterized by simple, leaf-like oval deirids (a unique feature among Rhabdochona spp.), a prostom with 14 anterior teeth, the presence of basal prostomal teeth, the length ratio of the muscular and glandular portions of oesophagus (1:2.1-2.6), an unusually long left spicule (1.10-1.22 mm), length ratio of spicules (1:11.5-14.7), arrangement of genital papillae, and conspicuously elevated vulval lips. Rhabdochona thaiensis differs from other representatives of the subgenus Globochona Moravec, 1972 possessing caudal projections on the tail tip in that it has only 2 claw-shaped projections located ventrally on the tail tip of both males and females; the species is mainly characterized by the presence of distinct pseudolabia, 8 anterior prostomal teeth, absence of basal teeth, bifurcated deirids, length ratio of the muscular and glandular portions of oesophagus (1:11.3-11.9), conspicuously short (135-141 microm) left spicule, arrangement of genital papillae, and somewhat elevated vulval lips. Fully developed eggs of R. pseudomysti and R. thaiensis remain unknown. These are the first nominal species of Rhabdochona reported from Thailand.

Nodular and sclerosing gastritis caused by Cylicospirura felineus in a puma (Puma concolor).

An adult male puma (Puma concolor), hit by a car in an urban area, died three days later despite the therapeutic support provided. At necropsy, multiple firm nodules were identified in the gastric mucosa. The nodules were coated by an intact mucosa with a central opening from which reddish and cylindrical nematodes protruded into the lumen. Twenty-seven nematodes were retrieved for morphological and morphometric evaluations. During histopathological examination of the gastric tissue, the adult nematodes appear in longitudinal and transverse sections, surrounded by thick bands of collagen, interspersed with mixed inflammatory infiltrates. The nematodes had an eosinophilic cuticle with caudal serrated projections (bulbar type), coelomyarian musculature, pseudocoelom, and females with uterus containing numerous larvated eggs, characteristics consistent with the Cylicospirura genus. Morphologically, female nematodes had six large tricuspid teeth in the oral cavity and the vulva had an opening anterior to the esophagus-intestinal junction. Male nematodes had five pairs of small papillae near the tip of the tail. These findings were consistent with Cylicospirura felineus. This parasite should be included in the differential diagnosis of nodular gastric wall lesions in wild felids.

Correlation of salivary antibody to carbohydrate larval antigen (CarLA) with health and gastrointestinal nematode parasitism in sheep under Ontario grazing conditions.

Leveraging mucosal immunity is a promising method for controlling gastrointestinal nematode (GIN) parasitism in sheep. Salivary antibody to carbohydrate larval antigen (sCarLA), a heritable measure of immunity to third-stage GIN larvae (L3), has been successfully applied to genetic improvement programs in New Zealand. However, sCarLA levels wane in the absence of ongoing GIN exposure. New Zealand's temperate climate permits year-round exposure to L3, but cold winters in boreal regions such as Ontario, Canada interrupt exposure for five months or more. This study investigated associations between sCarLA levels, GIN parasitism, and indicators of overall health in sheep grazing under Ontario conditions. A commercial flock of 140 Rideau cross ewe lambs were followed from approximately 30 days of age in May 2016 until November 2017, including lambing and lactation in the spring of 2017. Every 6-8 weeks during the grazing season and at mid-gestation in March 2017, fecal egg counts were performed, blood collected to assess serum albumin, globulin, and hematocrit, and pasture samples obtained to confirm exposure to infective larvae. Measurements of sCarLA level were performed at the beginning, middle, and end of each grazing season, and at mid-gestation. Spearman's rank correlation coefficients were calculated to compare sCarLA levels over time, and general linear mixed models created to evaluate associations between sCarLA levels, GIN fecal egg count, hematocrit, serum albumin, and serum globulin. Levels of sCarLA followed a similar seasonal pattern to GIN fecal egg counts with a 6-8 week delay; much higher sCarLA levels were observed in the second grazing season. The proportion of the flock with detectable sCarLA (≥ 0.3 units/mL) was 68.3 % by the end of the first grazing season, declined over winter to 43.9 % at lambing, and approached 100 % after 3 months of grazing in the second grazing season. Correlations between sCarLA levels over time were consistently positive, of weak to moderate strength, and significant (p < 0.05). At all time points, sCarLA level was significantly (p < 0.001) and negatively associated with fecal egg counts. The flock displayed minimal variability in hematocrit, serum albumin, and serum globulin; none of which were significantly associated with sCarLA levels. These results suggest that sCarLA can be maintained over winter and is a useful measure of immunity to GINs in sheep under Ontario grazing conditions.

Philometrids (Nematoda: Philometridae) from fishes of Lake Turkana, Kenya, including two new species of Philometra and erection of Afrophilometra gen. n.

The following four species (only females available) of the Philometridae (Nematoda: Dracunculoidea) were recorded from freshwater fishes of Lake Turkana, northwestern Kenya in 2007-2008: Philometra bagri (Khalil, 1965) from the subcutaneous tissue around the mouth, on gill covers and the fin base of the bayad Bagrus bajad (Forsskål) (Bagridae: Siluriformes), Philometra lati sp. n. from the abdominal cavity of the Nile perch Lates niloticus (Linnaeus) (Latidae: Perciformes), Philometra spiriformis sp. n. from capsules on the inner surface of gill covers of L. niloticus and Afrophilometra hydrocyoni (Fahmy, Mandour et El-Nafar, 1976) comb. n. from the fins of Hydrocynus forskahlii (Cuvier) (Alestidae: Characiformes). The new species P. lati is characterized mainly by the presence of distinct oesophageal teeth, absence of large cephalic lobes and caudal projections, and by a combination of other features. Philometra spiriformis differs from all congeners principally in the spirally coiled body and from individual species by a combination of other morphological features. The already known species P. bagri and A. hydrocyoni are redescribed based on light and scanning electron microscopy; findings of both these species in Kenya represent new geographical records.

Tissue-dwelling philometrid nematodes of the fish Arapaima gigas in Brazil.

The nematode Rumai rumai Travassos, 1960 (Philometridae) is redescribed from the tissues of the mouth, tongue, operculum and head of the arapaima, Arapaima gigas (Schinz) (Osteichthyes), from Mexiana Island, Amazon River Delta, Brazil. Additional data on the related Nilonema senticosum (Baylis, 1922) from the same host and locality are also presented. Rumai rumai is characterized by the presence of a sclerotized formation on the female cephalic end, dorsal and ventral cephalic projections, the shape and structure of the oesophagus and a conical caudal extremity. Males of both R. rumai and N. senticosum, specific parasites of the ancient arapaima fish in the Neotropics, remain unknown. The relationship between these tissue-dwelling nematodes and the aquaculture system of Mexiana Island is commented upon.

Description of Piscicapillaria bursata sp. nov. (Capillariidae) and Redescription of Parascarophis sphyrnae Campana-Rouget, 1955 (Cystidicolidae), Two Nematode Parasites of Hammerhead Sharks (Sphyrna spp.) off Australia.

PURPOSE: Data on helminth parasites in hammerhead sharks are scarce and, therefore, new examinations of these hosts are needed to recognize the species composition of their parasites, including nematodes. METHODS: Helminthological examinations of hammerhead sharks, Sphyrna lewini (Griffith et Smith) (209 specimens) and Sphyrna mokarran (Rüppell) (57 specimens) (Sphyrnidae, Carcharhiniformes), from off the northern coast of Australia revealed one new and one insufficiently known species of intestinal nematode parasites. These were studied with the use of light and scanning electron microscopy. RESULTS: Both nematode species are described. Piscicapillaria bursata sp. nov. (Capillariidae) from S. mokarran (type host) and S. lewini differs from its congeners mainly in the spicule length (330 µm), body length of gravid females 12.80-21.26 mm and in possessing a subterminal female anus. The specimens of Parascarophis sphyrnae Campana-Rouget, 1955 (Cystidicolidae) (type species of Parascarophis Campana-Rouget, 1955) collected from S. lewini made it possible to redescribe the female and, for the first time, to describe the male; the same species was also found in S. mokarran. Amended diagnosis of Parascarophis is provided. Parascarophis is mainly characterized by the presence of lateral alae, a unique feature within the Cystidicolidae, and by the cephalic structures (presence of a cuticular hood and a pair of anterolateral plate-like structures in the mouth). CONCLUSIONS: In addition to the discovery of a new nematode species, Pi. bursata sp. nov., the finding of Pa. sphyrnae in Australian waters represents a new geographical record of this parasite outside the Atlantic Ocean. The species of Parascarophis previously described from teleosts, P. bharatii Agrawal, 1965, P. oteroi Arya, 1992 and P. mulloidi Imam, Tawfik et Abdel Hady, 1982, are designated as species inquirendae and incertae sedis. The finding of P. sphyrnae in Australian waters represents a new geographical record of this parasite outside the Atlantic Ocean. Pa. sphyrnae had not been reported previously from beyond the Atlantic Ocean.

Three new species of Cucullanus (Nematoda: Cucullanidae) from marine fishes off New Caledonia, with a key to species of Cucullanus from Anguilliformes.

Based on light and scanning electron microscopical studies of nematode specimens from the digestive tract of some rarely collected anguilliform and perciform fishes off New Caledonia, three new species of Cucullanus Müller, 1777 (Cucullanidae) are described: C. austropacificus n. sp. from the longfin African conger Conger cinereus (Congridae), C. gymnothoracis n. sp. from the lipspot moray Gymnothorax chilospilus (Muraenidae), and C. incognitus n. sp. from the seabream Dentex fourmanoiri (Sparidae). Cucullanus austropacificus n. sp. is characterized by the presence of cervical alae, ventral sucker, alate spicules 1.30-1.65 mm long, conspicuous outgrowths of the anterior and posterior cloacal lips and by elongate-oval eggs measuring 89-108 × 48-57 µm; C. gymnothoracis n. sp. is similar to the foregoing species, but differs from it in the absence of cervical alae and the posterior cloacal outgrowth, in the shape and size of the anterior cloacal outgrowth and somewhat shorter spicules 1.12 mm long; C. incognitus n. sp. (based on female morphology) differs from other congeneric species parasitic in the Sparidae mainly in possessing cervical alae, the postequatorial vulva, phasmids situated at the mid-length of the tail and in the size of the eggs (75-84 × 45-66 µm). A key to species of Cucullanus parasitizing anguilliform fishes is provided.

TITLE: Trois nouvelles espèces de Cucullanus (Nematoda: Cucullanidae) de poissons marins au large de la Nouvelle-Calédonie, avec une clé des espèces de Cucullanus d'Anguilliformes. ABSTRACT: Sur la base d'une étude en microscopie photonique et électronique à balayage de spécimens de nématodes provenant du tube digestif de quelques poissons anguilliformes et perciformes rarement pêchés en Nouvelle-Calédonie, trois nouvelles espèces de Cucullanus Müller, 1777 (Cucullanidae) sont décrites : C. austropacificus n. sp. de Conger cinereus (Congridae), C. gymnothoracis n. sp. de Gymnothorax chilospilus (Muraenidae) et C. incognitus n. sp. de Dentex fourmanoiri (Sparidae). Cucullanus austropacificus n. sp. est caractérisé par la présence d'ailes cervicales, une ventouse ventrale, des spicules ailés de 1,30-1,65 mm de long, des excroissances remarquables des lèvres cloacales antérieure et postérieure et d'oeufs ovales et allongés mesurant 89-108 × 48-57 µm. C. gymnothoracis n. sp. est semblable à l'espèce précédente, mais en diffère en l'absence d'ailes cervicales et d'excroissance cloacale postérieure, par la forme et la taille de l'excroissance cloacale antérieure et par des spicules un peu plus courts de 1,12 mm. C. incognitus n. sp. (basé sur la morphologie de la femelle) diffère des autres espèces congénères parasites chez les Sparidae principalement par la possession d'ailes cervicales, une vulve postéquatoriale, des phasmides situés à mi-longueur de la queue et par la taille des oeufs (75­84 × 45­66 µm). Une clé des espèces de Cucullanus parasitant les poissons anguilliformes est fournie.

Metazoan parasite communities of two deep-sea elasmobranchs: the southern lanternshark, Etmopterus granulosus, and the largenose catshark, Apristurus nasutus, in the Southeastern Pacific Ocean.

Two deep-sea shark species were obtained as by-catch of the local fishery of the Patagonian toothfish, Dissostichus eleginoides, at depths ranging from 1000 to 2200 m off central and northern Chile. A total of 19 parasite taxa were found in 133 specimens of the southern lanternshark, Etmopterus granulosus, (n = 120) and largenose catshark, Apristurus nasutus, (n = 13). Fourteen taxa (four Monogenea, one Digenea, four Cestoda, one Nematoda, two Copepoda, one Annelida and one Thecostraca) were found in E. granulosus, whereas five taxa (one Monogenea, two Cestoda and two Nematoda) were found in A. nasutus. Representatives of Cestoda showed higher values of prevalence and a greater intensity of infection; this pattern is consistent with reports for elasmobranchs, but the monogenean richness was higher than that previously reported for related deep-sea sharks. Regarding E. granulosus, a positive and significant correlation between host length and abundance was found for six (four ectoparasites, one mesoparasite, and one endoparasite) of the 14 taxa recorded, but prevalence was significantly correlated with host length only for the monogenean Asthenocotyle sp. Although the sample size for A. nasutus was limited, we compared richness, abundance, diversity and evenness at the infracommunity and component community levels. All of these variables were higher for E. granulosus, but at the infracommunity level, abundance was higher for A. nasutus. All the parasite taxa (except two) represent new host and geographical records.

Evaluation of the effect of eprinomectin in young dairy heifers sub-clinically infected with gastrointestinal nematodes on grazing behaviour and diet selection.

Inappetence is commonly associated with parasitism and has been observed in both housed and pastured ruminants. In seeking a functional explanation for these observations, it has been hypothesised that parasitized animals may feed more selectively in order to proportionally increase the protein content of their diet and thus partially compensate for their reduced feed intake. Support for this theory is found principally in studies in housed animals under carefully controlled experimental conditions. Grazing animals face a far more heterogeneous environment and a multiplicity of potentially confounding factors that could influence diet selection. Controlled grazing of adjacent monocultures of grass and clover can mitigate some of these variables and was used in the current study to examine the dietary preference of dairy heifers with sub-clinical parasitic gastroenteritis when compared to those receiving regular anthelmintic treatments. Grazing behaviour and herbage intake rates were determined through the use of jaw-movement recorders, direct observation and short-term liveweight change. Consistent with previous observations and despite evidence that nematode burdens were low in the untreated control heifers, a reduction in daily grazing time of 56min (P=0.054) was observed in the control animals. There was, however, no evidence that the control heifers showed greater preference for clover compared with ryegrass: partial preference for clover was 73.0% in the untreated controls and 75.5% in the treated heifers. Furthermore control heifers were observed grazing the clover swards significantly (P=0.032) less frequently than the treated heifers. This study provides additional evidence in grazing cattle for parasite-induced inappetence, manifest as a reduction in grazing time and in subtle changes in ingestive behaviour. The observed partial preference for clover in both treated and control cattle was not significantly affected by the level of parasitism.