Trypanorhyncha from sharks of southern brazilian coast: Eutetrarhynchus vooremi sp. n. and two other species parasites of Mustelus (Pisces, Triakidae)

In the present paper, Eutetrahynchus vooremi sp. n., a cestode of the order Trypanorhyncha is proposed. The new species was recovered from sharks under the genus Mustelus (Pisces, Triakidae) and was compared to E. ruficollis, E. lineatus, E. leucomelanus, E. litocephalus and E. macrotrachelus. The main character, among others, considered to differ the species refers to the eggs filament, size of proglottids, tentacular hooks and lenght of pars postbulbosa. Two other known species are studied: Callitetrarhynchus gracilis (Rudolphi, 1819) from M. canis (Mitchill, 1815) and Nybelinia (N.) lingualis (Cuvier, 1817) from M. schmitti Springer, 1939 representing new host records.

Sapromyza lopesi sp. n. from Brazil: a species related to S. duodecimvittata (Frey, 1919) (Diptera: Lauxaniidae)

A new species, Sapromyza lopesi, is described from Brazil, and compared with its closest relative, S. duodecimvittata (Frey). Some remarks are made on the generic classification of South American Lauxaniidae as it affects these and other species.

Trypanosoma nupelianus sp. n. (Protozoa, Kinetoplastida) parasitizing rhinelepis aspera (Osteichthyes, Loricariidae) from Paraná river, Brazil

It is described Trypanosoma nupelianus sp. n. parasitizing Rhinelepis aspera taken from Paraná river (Itaipu reservoir, Brazil). Morphometric characters such as body length, width of the body and nucleus dimensions show that T. nupelianus sp. n. is different from other trypanosomes described for fishes from tropical regions.

Neohilgertia venusti Gen. N. SP. N. (Nematoda: Oxyuridae)from Thylamys venustus cinderellus (Thomas) Reig, Kirsch & Marshall, 1985 (Marsupialia: Didelphidae) in Burruyacu, Tucuman, Argentina - Systematic position and possible evolution

Neohilgertia gen. n. proposed for Oxyuridae nematodes from Thylamys venustus cinderellus (Marsupialia: Didelphidae) is described. The hypothesis about the possibility of a secondary parasitism for marsupials and the origin of the genus in the African Sciuridae parasite ancestors is discussed.

Eimeria vitellini n. sp. (Apicomplexa: eimeriidae) from the brazilian toucan Rhamphastos vitellinus vitellinus Lichtenstein (Aves: Picicformes: Rhamplastidae)

Eimeria vitellini n. sp. is described from the faeces of the Rhamphastos v. vitellinus. Oocysts broadly ellipsoidal to oval (egg-shaped), 22,6 x 18.3 (20.0-25.0 x 16.3-22.5) micronm, shapeindex (length/width) 1.2 (1.1-1.1). Oocyst wall a single colourless layer about 0.5 micronm thick, becoming thinner at one ectremity, at which point the oocyst usually ruptures. No oocyst residuum, but 1 or 2 small polr bodies of about 1.0-1.5 x 0.5-1.0 micronm. Sporocysts ellongated ellipsoid (pearshaped), 14.3 x 7.5 (13.8-15.0 x 6.9-7.5) micronm, shape-index (1.9 (1.8-2.0), with a thin colourless wall bearing a very delicate Stieda body: a conspicuous sub-Stieda body is present. Sporozoites with anterior and posterior regractile bodies and strongly recurved around a bulky, compact sporocyst residuum composed of relatively fine granules and spherules.

Culex saltanensis Dyar, 1928: natural vector of Plasmodium juxtanucleare in Rio de Janeiro, Brazil

Searching for the natural vector of Plasmodium juxtanucleare in an enzootic locality: Granjas Calábria (33% of the chickens infected), Jacarepaguá, in Rio de Janeiro, Brazil, 13 comparative captures of mosquitoes were carried out, simultaneously on man (out-doors) and on chiken (in a poultry-yard), between 6 and 9 p.m., from September to March 1989. Culex saltanensis was the most frequent species in captures on chicken, accounting for 41.7% of the mosquitoes collected on this bait, showing to be highly ornithophilic (90% captured on chicken versus 10% on man). Seven specimens of Cx. saltanensis were found naturally infected in granjas Calábria: five with mature pedunculate oocysts and two with sporozoites (on in the haemocoele and one in the salivary glands). These sporozoites porudced an infection by P. juxtanucleare in a chick, which had parasitemia on day 41 after inoculation. One Cx. coronator was found with mature pedunculate oocysts. Culex saltanensis was regarded as primary vector of P. juxtanucleare in Rio de Janeiro for being highly ornithophilic and in enough density to maintain the transmission, having been found with infective sporozoites in its salivary glands, and being susceptible to the parasite and able to transmit experimentally it by the bite.

Cellular immune response of humans to the circumsporozoite protein of Plasmodium vivax

The cellular immune response to the circumsporozoite (CS) protein of plasmodium vivax of individuals from malaria-endemic areas of Brazil was studied. We examined the in vitro proliferative response of the peripheral blood mononuclear cells (PBMC) of 22 individuals when stimulated with a CS recombinant protein (rPvCS-2) and two other synthetic peptides based on the sequenceof the P. vivax CS protein. Seven of the individuals from malaria-endemic area displayed an antigen specific in vitro proliferative responseto the recombinant protein PvCS-2 and one out of 6, proliferative response to the peptide 308-320. In contrast, none of the individuals displayed a proliferative reponse when stimulated with the D/A peptide which represent some of the repeated units present in this CS protein. Our study, therefore, provides evidence for the presence, withinthe major surface antigen of P. vivax sporozoites, of epitopes capble to induce proliferation of human PBMC.

Gastromermis cordobensis n. sp. (Nematoda: Mermithidae) parasitizing Simulium lahillei Patterson & Shannon (Diptera: Simuliidae) in Argentina

Gastromermis cordobensis n. sp (Nematoda: Mermithidae) a parasite of larvae of the blackfly Simulium lahillei Paterson & Shannon (Diptera: Simuliidae) in Argentina, is described. Diagnostic characters of this species include a mouth ventrlly shifted; six cephalic papillae; eigh hypodermal chords; small and pear shaped amphids; a long and S-shaped vagina; a singl spicule, which is long, has non-uniform walls, and a tip with sculpture; three rows of genital papillae, the middle one with 18 pre-anal and 10 post-anal papillae, the lateral rows have 36 papillae each; oval eggs; and post-parasitic juveniles with long thin tails. Pre-parasitic and parasitic juveniles are included in the description.

A new helminth parasite of fish: Spirocamallanus freitasi sp. n. (Nematoda - Camallanidae)

A new species of nematode is described, Spirocamallanus freitasi sp. n. The worms were collected from fishes (Bergiaria westermanni, Pimelodus maculatus and Pimelodus sp.) living in Três Marias Dam (São Francisco River) in the State of Minas Gerais, Brazil. Spirocamallanus freitasi sp. n. differs from Procamallanus iheringi, P. amarali, P. macaensis, P. (Spirocamallanus) pimelodus, P. (S.) solani and P. (S.) pereirai by having digitated larger spicule and from P. cruzi by having not digitated terminal parts of both spicules. It differs also from P. (S.) intermedius by having not larger spicule divided in two undigitated branches and six to nine sclerotized bands in the buccal capsule; P. rarus has three to four sclerotized bands and tridigitated larger branch of longer speicule, differing from S. feitasi sp. n.

Travassosnema gen. n. with the description of T. travassosi sp. n. (Dracunculoidea, Guyanemidae) parasite of Acestrorhynchus lacustris Reinhardt, 1874 (Characidae) from Três Marias Reservoir, MG, Brazil

A new genus, Travassosnema (Guyanemidae, Dracunculoidea) is proposed to include filariid worms having esophagus divided into muscular and glandular parts, with esophageal appendix near junction with intestine; anus functional; vulva anterior, well developed and functional in mature females. Travassonema travassosi sp. n., a parasite of Acestrorhynchus lacustris Reinhardt, 1874 from Três Marias Reservoir (São Francisco River) in the State of Minas Gerais, Brazil, is described. The generic and the specific names are a tribure to Brazilian parasitologist Lauro Travassos at his birth centenary.

Catadiscus pomaceae sp. n. (Trematoda, Paramphistomatidae) from Pomacea canaliculata (Lamarck, 1801) (Prosobranchia, Ampullariidae)

Catadiscus pomaceae sp. n. from the intestine of the prosobranch mollusc Pomacea canaliculata (Lamarck, 1801), is described. The host snail was collected from a lenitic biotope belonging to the Riachuelo basin (Corrientes province, Argentina) during 1985-1986. So far the species of the genus Catadiscus Cohn, 1904 have been recorded in amphibians and reptiles. This is the first instance of a species of that genus parasitizing a mollusc.

Parasites of commercial shrimps and fishes in Argentine sea: on the adult and metacercaria of Opecoeloides feliciae n. sp. (Digenea: Opecoelidae)

Opecoeloides feliciae n. sp., first record of opecoelid metacercariae in commercial shrimps of South Atlantic Ocean, parasitizing Cynoscion striatus (adults) and Artemesia longinaris (metacercariae), is described, illustrated and compared with related species of the genus. Adults, immature worms and metacercariae are compared, and rates of prevalence and intensity of infection are also given.