Paraorientatractis semiannulata n. g., n. sp. (Cosmocercoidea: Atractidae) from the Large Intestine of the SideNecked Turtle, Podocnemis unifilis Troschel, 1848 (Testudines: Pelomedusidae) in Brazil

Specimens collected from the large intestine of the sidenecked turtle Podocnemis unifilis Troschel, 1848 in the region of Cuminá and Trombetas rivers near Pará, Brazil are assigned to a new genus and new species of the nematode superfamily Cosmocercoidea and family Atractidae and named Paraorientatractis semiannulata. The new genus is separated from the nearest genus Orientatractis by the funnelshaped mouth opening, the presence of 4 distinct lips, 4 papillae in the internal cycle, one on each lip margin, 2 lateral amphids with large amphidial pores and absence of submedian papillae. It is also separated from Orientatractis and Proatractis by the presence of striated lateral alae which curve dorsally extending from mid oesophagus to mid tail, the difference in size of the vulvar opening and the presence of large transverse ridges or semiannules on the dorsal surface. The new species can be separated from the species of the genera Orientatractis and Proatractis by the characters that distinguish the genera and the arrangement of the caudal papillae on the male. A host/parasite list for Podocnemis spp. is included

Aplectana artigasi n.sp. (Nematoda: Cosmocercidae) from the Frog Eupsophus calcaratus (Anura: Leptodactylidae) in Southern Chile

A new species of nematode found in the intestine of Eupsophus calcaratus (Anura: Leptodactylidae) from Yaldad, Chile (45° 5'S;73° 43'W) is described. This new nematode is compared with other South American species of the genus. Aplectana artigasi differs from the only known Chilean species, Aplectana chilensis, as the former has a greater number of postanal papillae and a double papilla in the ventral region of the tail

Study on the Elimination of Angiostrongylus costaricensis First Stage Larvae in the Experimental Infection of Swiss Mice

Abdominal angiostrongylosis is a nematode infection of wild rodents. Human infection may result in severe abdominal disease and has been reported from several countries in the Americas. The domestic mouse, Mus musculus, has not been found with natural infection and, like other urban rodents, should not be considered a natural host for Angiostrongylus costaricensis. Quantification of parasitic forms released for transmission may better express the coevolutionary status in parasite-host relationship. With this objective, five groups of experimentally infected Swiss mice were followed for up to 155 days post-infection (PI) days and the quantification of first stage larvae (L1) output revealed: an irregular elimination of L1 and a huge variation in the patency period (1 to 114 days) and in the number of L1 eliminated daily by individual animals (1 to 6340 L1/g). Overall mortality was 72% (range: 28% to 100%) at seven weeks PI. In conclusion, abdominal angiostrongylosis in M. musculus presents high mortality and a very variable and irregular elimination of L1 in feces.

Scanning Electron Microscopy of Lagochilascaris minor Leiper, 1909 (Nematoda: Ascarididae)

Lagochilascaris minor Leiper, 1909 is a parasitic nematode with its biological cycle still unknown, even though it was found in humans, domestic and silvatic animals. Adult worms, collected by surgical drainage from a human patient from the State of Pará, Brazil, were micrographed using a scanning electron microscope. Morphological aspects of males and females such as cephalic structures, caudal papillae and cuticular patterns were analyzed and compared with the previous descriptions adding new data for the identification of this species.

On a New Species of Hysterothylacium (Nematoda: Anisakidae) from Cauque mauleanum (Pisces: Atherinidae) by Brightfield and Scanning Electron Microscopy

Hysterothylacium geschei n. sp. (Nematoda, Anisakidae) is described from the intestine of Cauque mauleanum (Steindachner) (Pisces: Atherinidae) from Lake Panguipulli (39º43'S; 72º13'W), Chile. Eleven (78.6%) out of 14 fish were infected, with a mean intensity (range) of 14.4 (1-55) worms. The new species can be differentiated from the two previously described species of freshwater fishes from South America by the presence of lateral alae, the number of caudal papillae, and the length of the spicules, oesophagus, intestinal caecum, distance vulva-anterior extremity and the length ratio intestinal caecum: ventricular appendix. From the fishes examined in Lake Panguipulli, including the introduced salmonid species Oncorhynchus mykiss (Walbaum) and the authochthonous species Basilichthys australis Eigenmann (Atherinidae) and Percichthys trucha (Valenciennes) (Percichthyidae), only one specimen of P. trucha was found parasitized by a third-stage larva of this species.

Binema bonaerensis n. sp. (Oxyurida: Thelastomatidae) parasite of Neocurtilla claraziana saussure (Orthoptera: Gryllotalpidae) in Argentina

The nematode Binema bonaerensis n. sp. (Oxyurida: Thelastomatidae) is described from the intestine of the mole cricket of Neocurtilla claraziana Saussure (Orthoptera: Gryllotalpidae) from Buenos Aires Province, Argentina. It is distinguished mainly by having a conical tail; three sclerotized arches in the buccal cavity; an excretory pore inmediately posterior to the base of the esophagus and the presence of five pairs of male genital papillae with one pair preanal and four pairs postanal.

Acute intestinal anisakiasis in Spain: a fourth-stage Anisakis simplex larva

A case of acute intestinal anisakiasis has been reported; a nematode larva being found in the submucosa of the ileum of a woman in Jaén (Spain). The source of infection was the ingestion of raw Engraulis encrasicholus. On the basis of its morphology, the worm has been identified as a fourth-stage larva of Anisakis simplex. In Spain, this is the ninth report of human anisakiasis and also probably the first case of anisakiasis caused by a fourth-stage larva of A. simplex.

In vitro activity of Brazilian strains of the predatory fungi Arthrobotrys spp. on free-living nematodes and infective larvae of Haemonchus placei

In vitro tests were carried out to assess the activity of 26 Brazilian isolates of predatory fungi of the genus Arthrobotrys on a free-living nematode (Panagrellus sp.) and on infective larvae of Haemonchus placei, a parasitic gastrointestinal nematode of cattle. The results showed that the free-living nematode Panagrellus sp. was the most preyed upon, compared to H. placei, for all the fungal treatments. Also, variable predatory capacity was observed for different fungal isolates belonging to the same genus when applied to different nematode species.

Nematodes of elasmobranch fishes from the southern coast of Brazil

New records for nematode species recovered from elasmobranch fishes in Brazil are established and new systematical arrangements proposed. Parascarophis sphyrnae Campana-Rouget, 1955 from the spiral valve of Sphyrna zygaena is referred for the first time in South America as a new host record. Procamallanus (S.) pereirai Annereaux, 1946, from the spiral valve of Raja castelnaui is reported parasitizing an elasmobranch host. Nematode larvae of the genera Anisakis, Contracaecum, Pseudoterranova and Raphidascaris are listed from the stomach and spiral valves of several hosts. Anisakidae larvae previously referred in Brazil in the genus Phocanema should be reallocated in Pseudoterranova. Nematodes of the genera Anisakis, Contracaecum, Pseudoterranova and Raphidascaris are reported for the first time parasitizing elasmobranchs in Brazil.

Vectorial competence of Aedes aegypti (Linnaeus 1762) Rio de Janeiro Strain, to Dirofilaria immitis (Leidy 1856)

Dirofilaria immitis (Leidy 1856), a nematode parasite, is the etiologic agent of canine heartworm disease and mosquitoes are essential intermediate hosts. Mosquito susceptibility to the worms differ with species, strains and also among individuals of the same strain. To evaluate the degree of susceptibility of Rio de Janeiro laboratory raised strain of Aedes aegypti, we fed mosquitoes on canine blood with different densities of microfilariae (mf). There was no significant difference in the rate of development among the three different densities of mf. Infective larvae were found in the head and proboscis of all mosquitoes provided bloodmeals with different densities of mf after the 11th day post-infection. The infection rate of mosquitoes after ingestion of blood containing 3,000 mf/ml, 5,000 mf/ml and 7,000 mf/ml were 55.3%, 66.7% and 100%, respectively. The vector efficiency indices ranged from 1.6 to 9.3. The finding of L3 stage larvae, high infection rates and vector efficiency indices suggest that Ae. aegypti, Rio de Janeiro laboratory strain, is a potential vector of D. immitis, although of low efficiency.

Human infection by Pseudoterranova decipiens (Nematoda, Anisakidae) in Chile: report of seven cases

From 1997 to 1999, we identified seven human cases of infection by fourth stage larvae of Pseudoterranova decipiens in Chile. All identified larvae were coughed up by the patients. Subjects were 10-55 years old; five were female. Some patients complained of coughing, expectoration, pharyngeal pain, nausea or anal and nasal pruritus. Larvae of three patients were coughed up from 36 h to 7 days after having eaten raw (cebiche or sushi) or lightly fried fish. P. decipiens has a marine life cycle. Infective third stage larva develop to adult stage in pinniped mammals. The nematode eggs are voided with the host faeces and develop and hatch releasing third stage larvae. Some crustaceans and fish act as hosts of third stage larvae. Man is an accidental host for third or fourth stage larvae.

Ecological Data of Travassosnema travassosi travassosi (Dracunculoidea: Guyanemidae) from the Humour of the Eyes of Acestrorhynchus lacustris from Tibagi River, Paraná, Brazil

Data obtained between 1990 and 1995 provide, for the first time, ecological information of the parasitic nematode Travassosnema travassosi travassosi Costa, Moreira & Oliveira, 1991 from Acestrorhynchus lacustris (Characiformes: Acestrorhynchidae) collected in the Tibagi River, Sertanópolis, Paraná, Brazil. These nematode occurred with low prevalences (7.7% to 28.6%) and intensities (1 to 3) during almost the whole year. The observation of mature females throughout the year indicate that liberation of larvae can occur during all the year around. This is the first report on the occurrence of T. travassosi travassosi inside the eyes. These nematodes were mostly located in humour of the eyes (87% of cases), being less frequently detected in tissues behind the eyes (13% of cases).

First Report of Lappetascaris lutjani Rasheed, 1965 (Nematoda, Ascaridoidea, Anisakidae) Parasitizing Trachipterus arawatae (Pisces, Lampridiformes) on the Atlantic Coast of Brazil

New host and geographical records are reported for the nematode Lappetascaris lutjani Rasheed, 1965, parasitizing the marine fish Trachipterus arawatae Clark, 1881 in Brazilian waters. Morphometric data and illustrations of the parasites are included.

Redescrição de Litomosoides brasiliensis Almeida, 1936 (Nematoda: Filariidae) Parasito de Anoura caudifera (Chiroptera: Phyllostomidae)

The study of the surface topography added details regarding the disposition of male caudal papillae, spicules and area rugosa apart from vulva and oral aperture. The occurrence of this nematode in the state of Amapá represents a new geographical distribution.

Mortality in immatures of the floodwater mosquito Ochlerotatus albifasciatus (Diptera: Culicidae) and effects of parasitism by Strelkovimermis spiculatus (Nematoda: Mermithidae) in Buenos Aires Province, Argentina

Life tables were constructed for six cohorts of immature stages of the floodwater mosquito Ochlerotatus albifasciatus (Macquart) in a park in Buenos Aires, highlighting the mortality attributable to the parasitic nematode, Strelkovimermis spiculatus Poinar & Camino. Two cohorts were selected to compare parasite incidence in all mosquito stages when low and high parasitism occurred. Development time of Oc. albifasciatus from first instar to adult was 7.7-10 days in the spring, 6 days in the summer, and 10.9-21.9 days in the fall. Survival was estimated as 0-1.4% in the spring, 2% in the summer and 0.2-4.4% in the fall. The highest "K" value (Killing power) occurred during a fall cohort when prevalence of the parasite was 86.9%, and the lowest in a spring cohort. Parasitism occurred during all seasons, but S. spiculatus persisted to adult only in the summer and fall, when adult mosquitoes developed from parasitized third and fourth instars larvae. The abundance of S. spiculatus differed between old and young larvae only when parasite prevalence was the highest. Although pupae and adults of Oc. albifasciatus were parasitized, no pupal mortality attributable to parasitism was recorded. The proportion of parasitized adults ranged from 14.2% and 5.7% in the two cohorts compared. Pupal wet weight and adult wing lengths did not differ between parasitized and unparasitized individuals.