The amphipod Gammarus fossarum as a natural true intermediate host of the nematode Raphidascaris acus

A single third-stage larva of the fish nematode Raphidascaris acus (Bloch, 1779) (body length 1.77 mm) was found in 1 of 775 gammarids Gammarus fossarum Koch examined from the Jihlava River, Czech Republic. This is the first confirmed record of the advanced L, of this species from an invertebrate host, showing that an invertebrate may serve as true intermediate host of this nematode, in addition to lower aquatic vertebrates. Until now, invertebrates have generally been considered as paratenic hosts of the second-stage larvae of R. acus.

Ascarophis mexicana n. sp. (Nematoda: Cystidicolidae) from two species of Epinephelus (Pisces) from the Gulf of Mexico in southeastern Mexico

A new cystidicolid nematode, Ascarophis mexicana n. sp., is described from the stomach of 2 species of the genus Epinephelus, E. morio and E. adscensionis (Pisces: Serranidae), from the Gulf of Mexico, southeastern Mexico (states of Yucatan and Veracruz). It is distinguished mainly by small body measurements (body length of male and female 3.39-4.18 mm and 5.94-6.23 mm, respectively), a conspicuously long left spicule (1.58-2.05 mm), length ratio of spicules (1:10-12), and by eggs provided with 2 filaments on 1 pole. Ascarophis mexicana is the second Ascarophis species known to parasitize fishes of the genus Epinephelus (groupers).

Philometra (Ranjhinema) salgadoi n. sp. (Nematoda: Philometridae) from the ocular cavity of the red grouper Epinephelus morio (Pisces: Serranidae) from the yucatan peninsula, Mexico

A new nematode species, Philometra (Ranjhinema) salgadoi n. sp., is described from females found in the ocular cavity of the red grouper (Epinephelus morio) from the Mexican coast of the Gulf of Mexico (type locality Telchac, Yucatán). The nematode is characterized by the presence of 8 conspicuously large, crescent-shaped, fleshy cephalic papillae of the external circle and 2 small, subterminal papilla-like projections on the caudal end. Another philometrid species, Philometroides belousae n. sp., is established by indication for P. parasiluri (Yamaguti, 1935) sensu Ermolenko, 1984; its adult females are parasitic in the subcutaneous tissues of Percottus glehni in the Russian Far East.

The first record of fish as paratenic hosts of Falcaustra spp. (Nematoda: Kathlaniidae)

Two types of third-stage nematode larvae (most of which were encapsulated) were collected from the abdominal cavity and liver of the freshwater fishes Etheostoma fonticola, Etheostoma lepidotum, Cichlasoma cyanoguttatum, Lepomis auritus, Lepomis sp., and Gambusia affinis in Texas and are referred to the genus Falcaustra. This is the first record of Falcaustra larvae from fishes, and their presence may reflect the importance of fishes as paratenic hosts of turtle parasites in this genus.

Life history of the nematode Rhabdochona hellichi, a parasite of the barbel in the Jihlava River, Czech Republic

From April 1992 until June 1993, the seasonal dynamics of Rhabdochona hellichi (Srámek, 1901) in its definitive host, the barbel (Barbus barbus), was studied in the Jihlava River (the Danube basin), Czech Republic. The parasite occurred in barbel throughout the year (overall prevalence 93% and intensity of infection 1-1384 [mean 78] nematodes per fish), but there were distinct seasonal fluctuations in prevalence and mean intensity values associated with the parasite's seasonal cycle of maturation. Prevalence was very high (usually 100%) during most months of the year, while lowest values were recorded in August and October. The highest values of mean intensity occurred in April. Both prevalence and mean intensity values increased with the body length of the hosts. The parasite exhibited a distinct annual cycle of maturation with egg-producing females present only from June until August, whereas larvae occurred in barbel mostly from September until April of the next year. Trichopteran (caddis-fly) larvae of the genus Hydropsyche (H. angustipennis and H. pellucidula) were found as natural intermediate hosts of R. hellichi (prevalence 4%, intensity 1-10 nematode larvae). The strictly seasonal maturation of this nematode may be associated with the temperature regime in the locality and seasonal cycles of maturation of its intermediate hosts.

Larval anisakid nematodes of Japanese common squid (Todarodes pacificus) from the Sea of Japan

Two species of third-stage larvae of the family Anisakidae are described from the Japanese common squid (Todarodes pacificus Steenstrup) from the Sea of Japan. The larvae of 1 of them, Anisakis simplex (Rudolphi, 1809), commonly occur encapsulated in the viscera of squid, whereas those of another 1, identified as Lappetascaris sp., are found free in the mantle musculature. The latter, characterized by the presence of a very long ventricular appendix, a conspicuous esophageal gland, and the structure of the cephalic end (presence of sclerotized supports of lip anlagen), previously were reported by various authors as members of the genera Contracaecum, Thynnascaris, or Hysterothylacium. It appears that the larvae form the mantle of squid belong to a hitherto undescribed Lappetascaris species whose adults parasitize an, as yet unknown, predatory marine fish.

Redescription of the male and first description of the female of Capillaria carioca Freitas et Lent, 1935 (Nematoda: Capillariidae), a parasite of the marine fish Sphoeroides testudineus

A redescription of the male and the first description of the female of the intestinal nematode Capillaria carioca Freitas et Lent, 1935 are presented on the basis of specimens collected from the type host, the marine fish Sphoeroides testudineus (Linnaeus) (Teleostei, Tetraodontoidei), from the Lagoon of Yucalpetén in the northern coast of Yucatan (Gulf of Mexico), Mexico. This species is characterized by a well-sclerotized spicule and by the presence of two large ventrolateral lobe-like papillae on the male caudal end and, therefore, is assigned to the subgenus Neocapillaria Moravec, 1987. C. carioca is reported from Mexico for the first time.

Structure of the cephalic end of two little-known oxyuroid genera, Travnema Pereira, 1938 and Cosmoxynemoides Travassos, 1949, parasites of fishes, as revealed by SEM

The cephalic end of the type species of pharyngodonid genera Travnema and Cosmoxynemoides, T. travnema Pereira, 1938 and C. aguirrei Travassos, 1949, parasites of Brazilian freshwater fishes, was studied by scanning electron microscopy. The mouth aperture of Travnema was found to be circular, surrounded by four cephalic papillae and two lateral amphids and the cuticle of the cephalic end had a conspicuous dense sculpture. On the other hand, the mouth aperture of Cosmoxynemoides was triangular, surrounded by three lip-like elevations covering the whole surface of the relatively flat cephalic extremity, each with two inner lobes separated one from another by a short groove; the lip-like elevations bore four medium-sized, kidney-shaped cephalic papillae and two minute amphids (two papillae on the dorsal elevation and one papilla and one amphid on each of two ventrolateral elevations); the cuticle of the cephalic end was smooth. Both species were noted for the absence of oral lamellae and the presence of lateral alae. Both genera are listed in the family Pharyngodonidae but Travnema (and also Hakynema), due to its morphological peculiarities, is considered to represent a distinct subfamily Travnematinae within the Pharyngodonidae. The finding of both T. travnema and C. aguirrei in the characid fish Astyanax bimaculatus lacustris represents new host records.

Seasonal occurrence and maturation of Neoechinorhynchus rutili (Acanthocephala) in barbel, Barbus barbus (Pisces), of the Jihlava River, Czech Republic

From April 1992 until June 1993, the seasonal occurrence and maturation of the acanthocephalan Neoechinorhynchus rutili in its definitive host, the barbel (Barbus barbus), was studied in the Jihlava River (the Danube basin), Czech Republic. The parasite occurred in barbel throughout the year (overall prevalence 84% and intensity of infection 1-533 [mean 25] acanthocephalars per fish), but there were distinct seasonal fluctuations in prevalence and mean intensity values: prevalence attained 100% in February and March, whereas its lowest value was recorded in July; the lowest values of mean intensity occurred in July-August. Both prevalence and mean intensity values distinctly increased with the body length of hosts. The parasite exhibited a distinct annual maturation cycle when egg-producing females were present mainly in the spring and summer (May-July) and, at a lesser extent, also from December to April of the next year. The seasonal maturation of N. rutili appears to be induced principally by the temperature regimen in the locality. N. rutili cystacanths were recovered from larval Sialis lutaria (Megaloptera) (prevalence 6%).

Brevimulticaecum sp. larvae (Nematoda: Anisakidae) from the frog Hyla minuta Peters in Trinidad

Enscapsulated third-stage nematode larvae collected from the abdominal cavity of the Trinidadian hylid frog Hyla minuta are referred to the rare anisakid genus Brevimulticaecum. These are the first specimens of Brevimulticaecum from a tropical frog, and their presence may reflect the importance of amphibians as intermediate or paratenic hosts of reptilian parasites.

Trichospirura amphibiophila n. sp. (Nematoda: Rhabdochonidae) in the frog Eleutherodactylus martinicensis from La Désirade, French Antilles

Trichospirura amphibiophila n. sp. (Nematoda) is described from the abdominal cavity (encapsulated near the liver) of the frog Eleutherodactylus martinicensis (Anura: Leptodactylidae) from the island of La Désirade in the French Antilles. It is characterized by the length of its spicules (459 microns and 90 microns) and their length ratio (1:5), by the presence of deirids and 7 pairs of caudal papillae in the male (2 preanal and 5 postanal), and by the site of localization (abdominal cavity) in the host. Trichospirura amphibiophila is the first known species of the genus parasitizing amphibians.

Description of Cosmocerca longispicula sp. nov. (Nematoda: Cosmocercidae), a parasite of a dendrobatid frog from Martinique, French Antilles

Cosmocerca longispicula sp. nov. (Nematoda: Cosmocercidae), a new cosmocercid nematode discovered in the intestine of a new dendrobatid frog from Martinique, French Antilles, is described and illustrated. It is unique in possessing unusually long, well-sclerotized spicules (length, 0.294-0.300 mm; length ratio of gubernaculum and spicules, 1: 2.1-2.2), a feature that necessitates emendation of the definition for the genus Cosmocerca. C. longispicula is the first known species of Cosmocerca from the Caribbean region. A new name, C. paraguayensis nom. nov., is proposed for C. uruguayensis Moravec and Barus, 1990, a homonym to C. uruguayensis Lent and Freitas, 1948.

[Isolation of Dirofilaria repens in vitreoretinal findings]

The authors present the case of a 18-year-old patient who reported deteriorated vision and mobile dark shadows on the left eye. Examination revealed in the vitreous body an extremely mobile filiform, worm-like formation, white in colour, of the size of an arteriole, about 9 mm long. In the course of hospitalization the formation was isolated by surgery of the pars plana vitrectomy and subjected to detailed helminthological examination. The worm was identified as Dirofilaria repens (Reillet et Henry 1911) and described in detail. The presented finding is the first finding of this parasite in this country and at the same time the first finding of this parasite in Czechoslovakia.

Observations on the occurrence and maturation of the nematode Rhabdochona denudata (Dujardin, 1845) in Chub, Leuciscus cephalus (L.), of the Rokytná River, Czechoslovakia

From October 1985 until July 1987, the seasonal dynamics of Rhabdochona denudata in its principal definitive host, the chub (Leuciscus cephalus), was studied in the Rokytná River (the Danube basin), Czechoslovakia. Prevalence (overall prevalence 77%) and intensity of infection (1-59 nematodes per fish) in the fish were high all year, with both abiotic and biotic factors influencing the fluctuations. Maximum values of prevalence (82-87%) were found in the fish with body length exceeding 20 cm; the mean intensity was highest in the size-group of fish 20-25 cm long, whereas its values gradually decreased in larger fish, this being due to the choice of food by fish of different size-groups. In contrast to the situation in other localities, an annual maturation cycle was not evident and egg-producing female nematodes were present in fish throughout the year. New infections in fish were most common in summer but occurred all year round. This life history pattern seems to be mainly due to the availability of infected ephemeropteran intermediate hosts during all seasons, in this case the nymphs of Ephemera danica, a species noted for its two-year development. In this locality, specifically not determined Rhabdochona larvae were recorded from the mayfly nymphs Ephemera danica (0.4%), Ecdyonurus aurantiacus (7%), and Caenis macrura (10%). The diet of the chub included mayfly nymphs at all seasons.