The genus lobatostoma (Trematoda: Aspidocotylea) in the pacific coast of South America, with description of Lobatostoma veranoi new species, parasite of Menticirrhus ophycephalus (Teleostei: Sciaenidae)

The presence of three aspidocotyleans trematodes in marine fishes from Perú and Chile is reported. One of them, Lobatostoma veranoi from the intestine of Menticirrhus ophicephalu (Sciaenidae) is considered a new species. Distinct characteristcs of the new species are:a cirrus sac smaller than the pharynx; tail overlapping posteriorly the ventral disk; testis in the last third of the body and the presence of 64-66 marginal alveoli. The two other species are Lobatostoma pacificum Manter, 1940 found in Trachinotus paitensis Cuvier, 1830 from Perú and Chile and Lobatostoma Anisotremum Oliva & Carvajal, 1984 from the intestine of Anisotremus scapularis (Tschudi, 1844) from Perú.

On Dichelyne (Cucullanellus) elongatus (Tornquist, 1931) Petter, 1974: South American correlated species (Nematoda, Cucullanidae) and some other helminths of micropogonias furnieri (Desmarest, 1823) (Pisces, Sciaenidae)

Dichelyne (Cucullanellus) elongatus (Tomquist, 1931) Petter, 1974, from Venezuela, of which D.(C.) amaurincai (Freitas, Vicente & Ibáñez, 1969) Petter, 1974 is proposed as a junior synonym, is redescribed and comments on the present status of the remaining species under the group, namely D.(C.) dichelyneformes (Szidat, 1950) Petter, 1974, D.(C.) rodriguesi (Pinto, Fábio & Noronha, 1970) Petter, 1974 and D.(C.) travassosi (Guimarães & Cristofaro, 1974), occuring in South America are made. Dollfusentis chandleri Golvan, 1969 (Acanthocephala, Illiosentidae), Poecilancistrium caryophyllum (Diesing, 1850)(Cestoidea, Otobothriidae) and Callitetrarhynchus gracilis (Rudolphi, 1819)(Cestoidea, Dasyrhynchidae) as well as larval forms of Echinocephalus sp. (Nematoda, Gnathostomatidae) and Contracaecum sp. (Nematoda, Anisakidae) are also reported.

Hyperparasitism by helminths: new records of cestodes and nematodes in proteocephalid cestodes from South American siluriform fishes

Proteocephalid cestode hyperparasite are reported from numerous proteocephalids occurring in pimelodid fishes in different regions of Brazil. In addition, three specimens of a nematode hyperparasite are reported from the proteocephalid cestode Choanoscolex abscissus from the pimelodid fish Pseudoplatystoma corruscans in Brazil. Previous records of cestode and nematode hyperparasite of cestode are listed, and the possible identities of the Brazilian records are discussed.

Two new species of Crawfordia Pierce from South America, (Strepsiptera: Stylopidae)

Several stylopized specimens were found among the Hymenoptera collection of the Instituto Oswaldo Cruz (Rio de Janeiro, Brazil). A paper by Kogan & Oliveira (1966) described the parasites of Polybia represented among those specimens. I describe herein the first neotropical species of the genus Crawfordia parasitizing species of Psaenithia (Andrenidae, Panurgini). The presence of vestigial thoracic segmentation of the female cephalothorax is a peculiar trait of this genus of Strepsiptera. Triungulinids are described in detail for the first time in this genus.

A new species of whipworm from a south american hystricomorph rodent

A new species of whipworm, Trichuris robusti, is described from the cecum and large intestine of rodent, Ctnomys robusti, collected in northern Chile. The nematode shows close affinityto T. bradleyi and T. chilensis, both having been described from Chile but because of the possession of ceertain specific morphological chareacters, particularly the disposition of the proximal cloacal tube, could not be assigned to either of them. A key is presented to some of the Trichuris species reported from hystricomorph rodents in Chile and the biographical significance of speciation of chilean trichurids is discussed.

A new species of Limnoderetrema (Trematoda, Digenea) from the freshwater Atherinid fish Basilichthys australis Eigenmann, 1927 from the south of Chile

Limnoderetrema tolosai sp. n. (Trematoda, Digenea) within an autochthonous freshwater fish, the silverside Basilichthys autralis Eigenmann, 1927, from Lakes Riñihue and Ranco in Southern Chile is described. The species is distinguished from Limnoderetrema minutum (Manter, 1954) by the presence of one spine in the cirrus and cecal bifurcation nearer to ventral sucker than to pharinx. It is proposed Limnoderetrema macrophallus (Szidat & Nani, 1951) n. comb. (originally Steganoderma). Limnoderetrema tolosai differs from L. macrophallus since it cirrus has a distal spine and by its vitelline follicles distribution. It seems that Limnoderetrema spp. of South America are highly specific unlike L. minutum of New Zealand.

Transmission and diagnosis of equine babesiosis in South Africa

The transmission and prevalence of Babesia equi and B. caballi are being studied. Rhipicephalus evertsi mimeticus an ixodid tick from Namibia was identified as a new vector of B. equi, however, R. turanicus, previously reported to be a vector, failed to transmit both B. equi and B. caballi in the laboratory. The accurate diagnosis of B. caballi is being investigated because the nature of its low level parasitaemia does not allow easy detection in thin blood smears, routinely used for diagnosis, by clinicians. Consequently its role as a pathogen remains obscure. The importance of identifying infected horses, destined for export to Babesia-free coutries, is also stressed. Thock and thin blood smears, serology (IFAT) and DNA probes are currently employed to study disease prevalence. To date 293 healthy, adult, throughbred horses have been screened by all three methods. The percentage positives are as follows: B. equi 4.4%, 70.6%, 13% and B. caballi 0.7%, 37%, 18.4% respectively. The DNA probes were more sensitive than blood smear examination for diagnosing carrier infections but are probably not sensitive enough to identify all carrier infections. A poor correlation was found between detection of the parasites' DNA and seropositivity. However, polymerase chain reaction could be used to amplify parasite DNA in a particular sample and its could result in more accurate diagnosis.

South American monkeys in the development and testing of malarial vaccines - a review

South American Aoutus an d Saimiri monkeys, which are susceptible to infection with human malarias, have been used to develop models for the testing of huma malaria vaccines. Studies indicate that blood-stage and sporozoite vaccines can be tested in these monkeys using appropriate strains of parasites.

Hepatitis B and C prevalences among blood donors in the south region of Brazil

The prevalence of hepatitis B and C infection has been determined in a seroepidemiological survey among blood donors from the south of Brazil (Florianópolis, State of Santa Catarina). These markers has also been correlated with the levels of alanine aminotransferase (ALT), a surrogate marker to prevent post-transfusion hepatitis. Sera from 5000 donors were randomly collected in the period of April to November 1991. The prevalences of HBsAg, anti-HBs and anti-HBc were respectively 0.78, 7.02 and 13.98. The anti-HCV prevalence after confirmation testing with line immunoassay (LIA), was 1.14. Normal values of ALT ( < = 32 U/ml) were found in 59.78, values slightly above the mean (ALT between 32-70 U/ml) in 37.74 and high values of ALT ( > = 70 U/ml) in 2.48. The positivity of anti-HCV antibodies increased with the elevation of ALT levels. This correlation was not observed in relation to HBsAg. There exists a diversity in the recognition of HCV epitopes among HCV positive donors. Via the confirmation test used, we could observe that 94.7 of donors recognize the structural core antigen. Besides that, we observed that 5.26 of the HCV reactive sera recognized only epitopes located in the NS4 and/or NS5 region, indicating the importance of these epitopes for the improvement of assays.

Taxonomy and biology of Culex (Culex) maxi Dyar (Diptera: Culicidae) in South America

Culex (Culex) maxi Dyar is described in the adult, pupal and larval stages, and the male genitalia and parts of the fourth-instar larva are illustrated. The larva is described for the first time. The paper includes a summary of available information on the taxonomy, bionomics and distribution of the species. The taxonomy and identification of the species are reviewed in light of current knowledge of the subgenus Culex in the New World.