Redescription of Philometra margolisi Moravec, Vidal-Martínez et Aguirre-Macedo, 1995 (Nematoda: Philometridae), a gonad-infecting parasite of the red grouper Epinephelus morio (Serranidae) in the Gulf of Mexico

The insufficiently known nematode species Philometra margolisi Moravec, Vidal-Martínez et Aguirre-Macedo, 1995 (Philometridae) is redescribed based on light and scanning electron microscopical (SEM) examinations of specimens collected from the gonad of the type host, the red grouper Epinephelus morio (Valenciennes) (Serranidae, Perciformes), in the northern Gulf of Mexico off Florida, USA. Also, new prevalence data for females of P. margolisi were derived from 188 fish, and a subset of these (n = 38) were used to determine prevalence and intensity of male nematodes. The male of this species was studied with SEM for the first time, which revealed some new, taxonomically important morphological features. The male posterior end had a V-shaped caudal mound, four pairs of minute adanal papillae, a pair of large papillae located posterior to the cloacal aperture and a pair of very small phasmids. The distal end of the gubernaculum is unique among all gonad-infecting species of Philometra parasitizing serranids in that its ventral surface is flat, smooth, without the usual two longitudinal grooves; the dorsal lamellate structures on the gubernaculum are also different in this species. In contrast to data in the original species description, the body length of gravid females of P. margolisi was 132-280 mm. Overall prevalence for male nematodes (76.3%) was much higher than for females (15.4%), and female nematode prevalence was higher in samples collected during host spawing season than out of season (27.1% and 3.3%, respectively).

Philometra rubra (Nematoda: Philometridae) — first description of the male from striped bass (Morone saxatilis) and implications for re-introduction of an extirpated population

Philometra rubra (Leidy, 1856) is a pathogenic parasitic nematode infecting striped bass (Morone saxatilis (Walbaum, 1792)) in eastern North America. Identification of philometrids is difficult, male P. rubra have never been found, and transmission is poorly understood. To re-establish the “Extirpated” striped bass population in the St. Lawrence Estuary (SLE), Quebec, young-of-the-year (YOY) striped bass from the Miramichi River, New Brunswick, were collected and released into the SLE. The present study was undertaken to find Philometra in striped bass from the Miramichi River, for identification, description, and examine transmission and lesions. Philometra rubra was identified in 100% of 32 YOY (intensity = 26–125) and 100% of nine 1-year-old (intensity = 4–25 in five striped bass) striped bass collected in summer 2011. The swim bladder and body cavity were sites of infection in YOY with no tissue response observed histopathologically. Gravid P. rubra females occurred in the body cavity and swim bladder, with males predominately in the latter site. Males were short-lived, being absent in 1-year-old bass. Adult male and adult female P. rubra are described. Males of P. rubra can be distinguished from other described species based on spicule, gubernaculum, and body-length measurements. This parasite may have implications for the re-introduction program and conservation of striped bass in the SLE and in other populations.

Species of Philometra (Nematoda, Philometridae) from fishes off the Mediterranean coast of Africa, with a description of Philometra rara n. sp. from Hyporthodus haifensis and a molecular analysis of Philometra saltatrix from Pomatomus saltatrix

Two gonad-infecting species of Philometra Costa, 1845 (Nematoda, Philometridae) were recorded for the first time from marine perciform fishes off Tunisia and Libya: Philometra rara n. sp. from the rare, deep-water Haifa grouper Hyporthodus haifensis (Serranidae) off Libya and Philometra saltatrix Ramachandran, 1973 from the bluefish Pomatomus saltatrix (Pomatomidae) off Tunisia. Identification of both fish species was confirmed by molecular barcoding. Light and scanning electron microscope studies of Ph. rara n. sp. showed that it is characterized by the length of spicules (216–219 μm) and the gubernaculum (90–93 μm), the gubernaculum/spicules length ratio (1:2.32–2.43), and mainly by the shape and structure of the distal end of the gubernaculum (shovel-shaped with a wide median smooth field in dorsal view), appearing as having a dorsal protuberance in lateral view, and by the structure of the male caudal mound (dorsally interrupted); large subgravid females (70–137 mm long) are characterized by the presence of four oval submedian cephalic elevations, each of them bearing a pair of cephalic papillae of the outer circle. The finding of Ph. saltatrix off Tunisia confirms that this species is widespread throughout the Mediterranean region. A molecular analysis of our Ph. saltatrix specimens and other available philometrid cytochrome c oxidase 1 (COI) sequences showed that most species have robust clades. Sequences of Ph. saltatrix from Tunisia diverge from Ph. saltatrix from Brazil and the USA, suggesting that speciation is currently occurring between populations from both sides of the Atlantic Ocean.

Redescription of Rhabdochona papuanensis (Nematoda: Thelazioidea), a parasite of rainbow fishes (Melanotaenia spp.); the first record of the species of Rhabdochona in Australia

Numerous specimens of the parasitic nematode Rhabdochona papuanensis Moravec, Riha et Kuchta, 2008 (Spirurida: Rhabdochonidae) were collected from the intestines of the Australian endemic freshwater fish (eastern rainbow fish) Melanotaenia splendida (Peters) (Melanotaeniidae, Atheriniformes) in the Behana Creek, North Queesland during November of 2015. Although many species of Rhabdochona Railliet, 1916 are known to be common parasites of fishes in other continents, the present finding of R. papuanensis represents the first record of the species belonging to this genus from the Australian mainland. Light and scanning electron microscopical examinations of these newly collected specimens made it possible to redescribe in detail this nematode species, originally incompletely described from a congeneric host in Papua New Guinea. Fully developed, filamented eggs of R. papuanensis and the conspecific fourth-stage larva are described for the first time. The present finding of R. papuanensis in M. splendida from Australia represents new host and geographical records.

Nematode parasites of four species of Carangoides (Osteichthyes: Carangidae) in New Caledonian waters, with a description of Philometra dispar n. sp. (Philometridae)

Parasitological examination of marine perciform fishes belonging to four species of Carangoides, i.e. C. chrysophrys, C. dinema, C. fulvoguttatus and C. hedlandensis (Carangidae), from off New Caledonia revealed the presence of nematodes. The identification of carangids was confirmed by barcoding of the COI gene. The eight nematode species found were: Capillariidae gen. sp. (females), Cucullanus bulbosus (Lane, 1916) (male and females), Hysterothylacium sp. third-stage larvae, Raphidascaris (Ichthyascaris) sp. (female and larvae), Terranova sp. third-stage larvae, Philometra dispar n. sp. (male), Camallanus carangis Olsen, 1954 (females) and Johnstonmawsonia sp. (female). The new species P. dispar from the abdominal cavity of C. dinema is mainly characterised by the body length (5.14 mm), the lengths of markedly unequal spicules (163 and 96 μm) and gubernaculum (102 μm long) provided with a dorsal protuberance and a small, reflexed dorsal barb on its posterior portion. The finding of C. bulbosus represents the first record of this parasite a century after its discovery; the first study of this species by scanning electron microscopy (SEM) enabled detailed redescription. The finding of Johnstonmawsonia sp. in C. fulvoguttatus is the first record of a rhabdochonid nematode from a host belonging to the Carangidae family. Johnstonmawsonia africana Moravec & Puylaert, 1970 and J. campanae Puylaert, 1973 are transferred to Prosungulonema Roytman, 1963 as P. africanum (Moravec & Puylaert, 1970) comb. n. and P. campanae (Puylaert, 1973) n. comb.

Philometra dissimilis n. sp. from the ovary of Johnius belangerii (Sciaenidae) and other new records of philometrids (Nematoda: Philometridae) from fishes of the Bay of Bengal, India

Based on light and scanning electron microscopical studies, a new gonad-infecting species of Philometra Costa, 1845, P. dissimilis n. sp. (Nematoda: Philometridae), is described from the marine fish (Belanger’s croaker) Johnius belangerii (Cuvier) (Sciaenidae, Perciformes) in the Bay of Bengal, off the eastern coast of India. The species is mainly characterized by the body length of male 2.73 – 3.37 mm and that of gravid female 145 – 171 mm, needle-like, equal spicules 96 – 120 μm long, length of the gubernaculum 75 – 90 μm, distal end of the gubernaculum with lamellar structures forming a simple dorsal protuberance and by the V-shaped male caudal mound. Philometra dissimilis is the seventh known gonad-infecting species of this genus parasitizing sciaenid fishes. Moreover, an additional two species of Philometra (only females) were recorded from fishes in the Bay of Bengal: P. lobotidisMoravec, Walter et Yuniar, 2012 from the abdominal cavity of Lobotis surinamensis (Bloch) (Lobotidae, Perciformes), which is a new geographical record, and Philometra sp. from the ovary of Platycephalus indicus (Linnaeus) (Platycephalidae, Scorpaeniformes), representing probably an undescribed species.

Two gonad-infecting species of Philometra (Nematoda: Philometridae) from groupers (Serranidae) off Tunisia, with a key to Philometra species infecting serranid gonads

Based on light and scanning electron microscopical studies of nematode specimens (males and mature females) collected from the ovary of groupers (Serranidae, Perciformes) in the Mediterranean Sea off Tunisia (near Tunis and Sfax), two gonad-infecting species of Philometra Costa, 1845 (Nematoda, Philometridae) are reported: Philometra inexpectata n. sp. from the mottled grouper Mycteroperca rubra and P. jordanoi (López-Neyra, 1951) from the dusky grouper Epinephelus marginatus. Identification of both fish species was confirmed by molecular barcoding. The new species is mainly characterized by the length of equally long spicules (147–165 μm), the gubernaculum (63–93 μm long) bearing at the tip two dorsolateral lamellar parts separated from each other by a smooth median field, a V-shaped mound on the male caudal extremity, the presence of a pair of large caudal papillae located posterior to the cloaca and by the body length of the males (1.97–2.43 mm). Philometra inexpectata n. sp. is the fifth known gonad-infecting philometrid species parasitizing serranid fishes in the Mediterranean region. The males of P. jordanoi were examined by scanning electron microscopy for the first time; this detailed study revealed some new taxonomically important morphological features, such as the number and arrangement of cephalic and caudal papillae, presence of amphids and phasmids and mainly the lamellate structures at the posterior end of the gubernaculum. A key to gonad-infecting species of Philometra parasitic in serranid fishes is provided.

Redescription of two species of cystidicolid nematodes (Spirurina: Cystidicolidae) from Notopterus notopterus (Osteichthyes) in Thailand

Two nematode species, Pseudoproleptus notopteri (Karve et Naik, 1951) and Spinitectus notopteri Karve et Naik, 1951 (both Cystidicolidae), are redescribed based on light and scanning electron microscopical studies of specimens collected from the digestive tract of the freshwater fish Notopterus notopterus (Pallas) (Notopteridae, Osteoglossiformes) in Thailand. Some new important morphological features, such as a detailed structure of the cephalic end and the presence of bifurcate deirids and a ventral median caudal protuberance in male, are reported for the former species (P. notopteri), which is provisionally assigned to Pseudoproleptus Khera, 1955; Notopteroides notopteri Chakravarty et Majumdar, 1962, Pseudoproleptus satendri Sahay, 1967, P. lamyi Le-Van-Hoa et Bui-Thi Lien-Huong, 1969, P. gomtii Gupta et Bakshi, 1984. P. sprenti Gupta et Masoodi, 1986 and P. thapari Gupta et Naiyer, 1992 are considered its junior synonyms. The first study of S. notopteri by SEM showed its morphological similarity with S. mastacembeli Karve et Naik, 1951, from which it clearly differs by the structure of eggs; Spinitectus alii Kalyankar, 1970, S. bengalensis Chakravarty, Sain et Majumdar, 1961, S. gomalensis Siddiqui et Kattak, 1984 and S. thapari Ali, 1957 are considered to be junior synonyms of S. notopteri. Pseudoproleptus notopteri and Spinitectus notopteri are reported from Thailand for the first time.

New records of philometrids (Nematoda: Philometridae) from marine fishes off Iraq, with the erection of two new species and the first description of the male of Philometroides eleutheronemae Moravec & Manoharan, 2013

Based on light and scanning electron microscopical studies, the following five species of philometrid nematodes (Nematoda: Philometridae) are described from marine fishes from off Basrah, southern Iraq (Arabian Gulf): Philometra iraqiensis n. sp. (females) from the abdominal cavity and ovary of the Klunzinger's mullet Liza klunzingeri (Day) (Mugiliformes: Mugilidae), P. megalaspidis n. sp. (females) from the ovary of the torpedo scad Megalaspis cordyla (Linnaeus) (Perciformes: Carangidae), Philometra sp. 1 (females) from the ovary of the greater lizardfish Saurida tumbil (Bloch) (Aulopiformes: Synodontidae), Philometra sp. 2 (females) from the ovary of the bartail flathead Platycephalus indicus (Linnaeus) (Scorpaeniformes: Platycephalidae) and Philometroides eleutheronemae Moravec & Manoharan, 2013 (male and females) from the ovary of the fourfinger threadfin Eleutheronema tetradactylum (Shaw) (Perciformes: Polynemidae). The new species are characterised mainly by the body length, the length and structure of the oesophagus and caudal end and by the family of their fish hosts. The male and the gravid female of P. eleutheronemae are described for the first time; the finding of this species in Iraqi waters represents the first record of this nematode in the region of the Arabian (=Persian) Gulf.

Redescription of Philometra globiceps (Rudolphi, 1819) (Nematoda: Philometridae), the type species of Philometra Costa, 1845, including the first data obtained by SEM

A redescription of Philometra globiceps (Rudolphi 1819), the type species of Philometra Costa 1845 (Philometridae), is provided on the basis of specimens collected from the gonads, stomach, pyloric caeca, intestine and gallbladder of the marine fish Uranoscopus scaber Linnaeus (Uranoscopidae, Perciformes) caught in the Ionian Sea off Ugento, southern Italy. Light microscopical and scanning electron microscopical examinations (latter used for the first time in this species) of the specimens revealed some previously unreported morphological features, such as the location of submedian pairs of cephalic papillae of external circle on four elevated cuticular lobes in gravid females, the presence of amphids, genital papillae and phasmids in males, the lamellate structure of the distal end of gubernaculum appearing as a dorsal protuberance in lateral view and the structure of the male caudal end. A taxonomically important feature of P. globiceps is the details in the dorsal transverse lamella-like structures on the distal end of the gubernaculum, by which this species can be separated from other gonad-infecting species of this genus. Apparently, P. globiceps is a specific parasite of U. scaber and all previous records of this species from hosts belonging to other fish families are evidently based on misidentifications.

Two Procamallanus (Spirocamallanus) species (Nematoda: Camallanidae) from freshwater fishes in the Lower Congo River

Based on light and scanning electron microscopical studies, one known and one previously undescribed Procamallanus (Spirocamallanus) species (Nematoda: Camallanidae) are described from specimens collected in the intestine of freshwater fishes in the Lower Congo River, Democratic Republic of Congo: P. (S.) daleneae (Boomker 1993) from Synodontis acanthomias Boulenger (Mochokidae, Siluriformes) (new host and geographical records) and P. (S.) parachannae sp. nov. from Parachanna insignis (Sauvage) (Channidae, Perciformes). The new species is most similar to P. (S.) serranochromis Moravec et Van As 2015, a parasite of African cichlids (Serranochromis spp.), differing from it mainly in the absence of any outgrowths on the female tail tip, a distinctly longer (546 μm) right spicule, a different length ratio of both spicules (1:2.6) and in the morphology of fourth-stage larvae. P. (S.) daleneae, a specific parasite of squeakers (Synodontis spp.), is redescribed; in contrast to the original description, the number of postanal papillae was found to be identical (6 pairs) with that of other related species.

Studies on some spirurids (Nematoda: Spirurida) from fishes of the Okavango River, Botswana

Based on light and scanning electron microscopical studies, three adult spirurid nematode species, Camallanus (Zeylanema) ctenopomae Vassiliadès & Petter, 1972, Paracamallanus cyathopharynx (Baylis, 1923) (both Camallanidae) and Spinitectus polli Campana-Rouget, 1961 (Cystidicolidae), are redescribed from specimens collected in fishes of the Okavango River, Botswana: C. (Z.) ctenopomae from Ctenopoma sp. (Anabantidae), P. cyathopharynx from Clarias stappersi Boulenger, C. theodorae Weber (both new hosts, Clariidae) and C. gariepinus (Burchell), as well as S. polli from Synodontis nigromaculatus Boulenger (new host, Mochokidae). Moreover, spirurid larvae of an additional three species were found in fishes from the same locality: Rhabdochona paski Baylis, 1928 fourth-stage larva (Rhabdochonidae) in S. nigromaculatus (Mochokidae), Physalopteridae gen. sp. 1 third-stage larva in C. gariepinus (Clariidae) and Physalopteridae gen. sp. 2 third-stage larva in Serranochromis angusticeps (Boulenger) (Cichlidae), all representing new host and geographical records. Spinitectus zambezensis Boomker, 1993 is considered a junior synonym of S. polli.

Two gonad-infecting species of Philometra (Nematoda: Philometridae) from marine fishes off the northern coast of Australia

Two different gonad-infecting species of Philometra Costa, 1845 were collected from the ovary of marine perciform fishes, the blackspotted croaker Protonibea diacanthus (Sciaenidae) and the John’s snapper Lutjanus johnii (Lutjanidae), from off the northern coast of Australia. Nematodes (males and females) from P. diacanthus represent a new taxon, Philometra protonibeae n. sp., which is mainly characterized by the body length of the males (3.37–3. 90 mm), broad, equally long spicules (length 126–141 μm) and the shape and structure of the gubernaculum with a dorsally lamellate distal tip. The nematodes (only females) from L. johnii may represent an undescribed species, but, because of the absence of conspecific males, they could not be specifically identified. Philometra protonibeae is the fifth nominal gonad-infecting species of this genus recorded from marine fishes in Australian waters and the seventh species of these parasites described from fishes of the family Sciaenidae.

Procamallanus (Procamallanus) spp. (Nematoda: Camallanidae) in fishes of the Okavango River, Botswana, including the description of P. (P.) pseudolaeviconchus n. sp. parasitic in Clarias spp. (Clariidae) from Botswana and Egypt

Parasitological dissections of fishes from the Okavango River, Botswana, revealed the presence of nematodes of the subgenus Procamallanus (Procamallanus) Baylis, 1923 in five fish species belonging to three different families. Based on light and scanning electron microscopical examinations, they proved to represent one previously known and one new species, i.e. P. (P.) laeviconchus (Wedl, 1861) from Synodontis nigromaculatus Boulenger, S. thamalakanensis Fowler (new host) (both Mochokidae) and Schilbe intermedius Rüppel (new host) (Schilbeidae), and P. (P.) pseudolaeviconchus n. sp. from Clarias stappersi Boulenger and C. theodorae Weber (both Clariidae). Specimens of the new species previously collected from Clarias gariepinus (Burchell) (type-host) in Egypt were also examined. Both of these nematode species are very similar, differing from each other mainly in the shape of the circumoral flange, which is conspicuously lobed in P. laeviconchus and unlobed in P. pseudolaeviconchus. Previously, these two species have been confused in the literature under the name P. laeviconchus. A key to Procamallanus (Procamallanus) spp. parasitising freshwater fishes in Africa, including Madagascar, is provided.

Capillaria plectropomi n. sp. (Nematoda: Capillariidae), a new intestinal parasite of the leopard coral grouper Plectropomus leopardus (Serranidae) off New Caledonia

A new nematode species, Capillaria plectropomi n. sp. (Capillariidae), is described from the intestine of the leopard coral grouper Plectropomus leopardus (Lacepède) from coral reefs off New Caledonia. The new species, belonging to the subgenus Neocapillaria Moravec, 1987, differs from other congeneric species of this subgenus from marine fishes mainly in the length (168–186 μm), shape and structure of the spicule. It is characterized, in the male, by the presence of two well-developed dorsolateral caudal lobes, a pair of lateral papillae, a heavily sclerotized spicule with many rough transverse grooves in the middle part, a spinose spicular sheath, and in the female, by eggs measuring 60–66 × 27 μm without protruding polar plugs. The buccal cavity contains a small finger-shaped stylet. Capillaria plectropomi n. sp. is the first known species of this genus parasitizing fishes of the perciform family Serranidae.

Fauna europaea: helminths (animal parasitic)

Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. Helminths parasitic in animals represent a large assemblage of worms, representing three phyla, with more than 200 families and almost 4,000 species of parasites from all major vertebrate and many invertebrate groups. A general introduction is given for each of the major groups of parasitic worms, i.e. the Acanthocephala, Monogenea, Trematoda (Aspidogastrea and Digenea), Cestoda and Nematoda. Basic information for each group includes its size, host-range, distribution, morphological features, life-cycle, classification, identification and recent key-works. Tabulations include a complete list of families dealt with, the number of species in each and the name of the specialist responsible for data acquisition, a list of additional specialists who helped with particular groups, and a list of higher taxa dealt with down to the family level. A compilation of useful references is appended.