Gundlachia dutrae: n. sp. from northwest Brazil (Mollusca: Basommatophora: Ancylidae)

A new species of Gundlachia, Gundlachia dutrae is described from northwest Brazil. It is distinguishable from other congenerie species by characteristics of the shell, radula and internal organs. Shell relatively high. Aperture near-circular; periostracum dark brown without periostracal hairs. Apex slightly inclined to the right, projected but not hooked, with an apical depression surrounted by a sculpture of well-marked irregular punctations. Shell surface with prominent radial sculpture. No septate specimens were observed. Ratios (n= 59): shell width/shell lenght = 0,66- 0,79 (mean 0,73); shell height/shell length = 0,32- 0,45 ( mean 0,37); shell height/shell width = 0,43- 0,63 (mean 0,51). Body of normal ancylid type; mantle pigmentation dark brown or black, concentrated along the mantle collar. The dorsal surface of the right anterior muscle is elongated and medially constricted. The left anterior and the posterior muscles are almost elliptical. Adhesive area is V-shaped. Pseudobranch unpigmented bearing a very small and thin dorsal lobe. Ovotestis with more than 25 unbranched diverticula. Ovispermiduct with seminal vesicle rather developed. Elongated nidamental gland continous with the glandular wall of the uterus. Nidamental gland appendix ending into a bulbous swelling Spermathecal body almost rounded. Well-developed prostate with five long diverticula. Ejaculatory complex with long glandular flagellum, without a penis or true ultra-penis. "Penis sheath" developed. "Ultra-penis" projected as a tube inside the lumem of prepuce, with a slit between "ultra-penis" and "penis sheath". Rachidian tooth tetracuspid, with two median cusps assymmetrical and aculeated. Lateral teeth tricuspid, with a reduced endocon and a prominent mesocon. A well marked gap occurs between meso and ectocon. Marginal teeth similar to lateral ones. Jaw T-shaped, with about 28 dorsal plates.

Aspects of immunity for the AMA-1 family of molecules in humans and non-human primates malarias

The apical membrane antigen (AMA-1) family of malaria merozoite proteins is characterised by a high degree of inter-species conservation. Evidence that the protein (PK66/AMA-1) from the simian parasite Plasmodium knowlesi was protective in rhesus monkeys suggested that the 83kDa P. falciparum equivalent (PF83/AMA-1) should be investigated for protective effects in humans. Here we briefly review pertinent comparative data, and describe the use of an eukaryotic full length recombinant PF83/AMA-1 molecule to develop a sensitive ELISA for the determination of serological responses in endemic populations. The assay has revealed surprisingly high levels of humoral response to this quantitatively minor antigen. We also show that PK66/AMA-1 inhibitory mAb's are active against merozoites subsequent to release from schizont-infected red cells, further implicating AMA-1 molecules in red cell invasion.

Ecotopes, Natural Infection and Trophic Resources of Triatoma brasiliensis (Hemiptera, Reduviidae, Triatominae)

Triatoma brasiliensis is considered as one of the most important Chagas disease vectors in the northeastern Brazil. This species presents chromatic variations which led to descriptions of subspecies, synonymized by Lent and Wygodzinsky (1979). In order to broaden bionomic knowledge of these distinct colour patterns of T. brasiliensis, captures were performed at different sites, where the chromatic patterns were described: Caicó, Rio Grande do Norte (T. brasiliensis brasiliensis Neiva, 1911), it will be called the "brasiliensis population"; Espinosa, Minas Gerais (T. brasiliensis melanica Neiva & Lent 1941), the "melanica population" and Petrolina, Pernambuco (T. brasiliensis macromelasoma, Galvão 1956), the "macromelasoma population". A fourth chromatic pattern was collected in Juazeiro, Bahia the darker one in overall cuticle coloration, the "Juazeiro population". At the sites of Caicó, Petrolina and Juazeiro, specimens were captured in peridomiciliar ecotopes and in wilderness. In Espinosa the specimens were collected only in wilderness, even though several exhaustive captures have been performed in peridomicile at different sites of this municipality. A total of 298 specimens were captured. The average registered infection rate was 15% for "brasiliensis population" and of 6.6% for "melanica population". Specimens of "macromelasoma" and of "Juazeiro populations" did not present natural infection. Concerning trophic resources, evaluated by the precipitin test, feeding eclecticism for the different colour patterns studied was observed, with dominance of goat blood in household surroundings as well as in wilderness

Metazoan Parasite Infracommunities in Five Sciaenids from the Central Peruvian Coast

Parasitological analysis of 237 Menticirrhus ophicephalus, 124 Paralonchurus peruanus, 249 Sciaena deliciosa, 50 Sciaena fasciata and 308 Stellifer minor from Callao (Perú) yielded 37 species of metazoan parasites (14 Monogenea, 11 Copepoda, 4 Nematoda, 3 Acanthocephala, 1 Digenea, 1 Aspidobothrea, 1 Eucestoda, 1 Isopoda and 1 Hirudinea). Only one species, the copepoda Bomolochus peruensis, was common to all five hosts. The majority of the components of the infracommunities analyzed are ectoparasites. The Brillouin index (H) and evenness (J´) were applied to the fully sampled metazoan parasite infracommunities. High values of prevalence and mean abundance of infection are associated to the polyonchoinean monogeneans; the low values of J' reinforce the strong dominance of this group in the studied communities. The paucity of the endoparasite fauna may be a consequence of the unstable environment due to an upwelling system, aperiodically affected by the El Niño Southern Oscillation phenomena.

Triatoma jurbergi sp. n. do Norte do Estado do Mato Grosso, Brasil (Hemiptera, Reduviidae, Triatominae) com uma Atualização das Sinonímias e outros Táxons

Triatoma jurbergi n. sp. is described based on nine specimens of both sexes deposited in the Rodolfo Carcavallo Collection in the Oswaldo Cruz Institute Entomological Collection. The new species can be separated from the closely related Triatoma guazu Lent & Wygodzinsky, 1979 by several characters. The most important are longer anteocular region; thin and pointed juga; the shape of the eyes without concavity in the posterior edge; much longer second rostral segment, passing the posterior edge of eye; the absence of a ventral longitudinal depression on the abdomen; the general color redish, brown and orange and the male genitalia, mainly in the vesica lightly chitinized and smaller, the phallosome with apical projection and the pointed apex of the endosome process.

Scolex Morphology of Proteocephalid Cestodes Parasites of Neotropical Freshwater Fishes

The morphology of the scolices and metascolices of 29 proteocephalid species, parasites of freshwater fishes from Brazil was compared by using scanning electron microscope, light and laser microscopy. The following species were evaluated: Proteocephalus vazzolerae, P. piramutab, Robertiella paranaensis, Travassiella avitellina, Monticellia loyolai, M. spinulifera, M. belavistensis, Houssayela sudobim, Zygobothrium megacephalum, Gibsoniela mandube, Cangatiella arandasi, Nomimoscolex sudobim, N. lopesi, N. admonticellia, N. piraeeba, N. pirarara, Harriscolex kaparari, Crepidobothrium eirasi, Spatulifer rugosa, Megathylacus brooksi, Choanoscolex abscisus, Amphoteromorphus peniculus, A. piraeeba, Paramonticellia itaipuensis, Peltidocotyle rugosa, Othinoscolex lenha, Rudolphiella rugata, R. piranabu, Jauella glandicephalus. Some features as overall shape of scolex, suckers, apical sucker, frontal glands and several kinds of metascolex were analyzed. The taxonomic importance of scolex and metascolex is discussed.

Community ecology of the metazoan parasites of white croaker, Micropogonias furnieri (Osteichthyes: Sciaenidae), from the coastal zone of the State of Rio de Janeiro, Brazil

One hundred specimens of white croakers, Micropogonias furnieri (Desmarest 1823) (Osteichthyes: Sciaenidae) collected from Pedra de Guaratiba (23°01'S, 43°38'W), State of Rio de Janeiro, Brazil, from September 1997 to August 1999, were necropsied to study their parasites. The majority of the fish (95%) were parasitized by metazoan. Twenty-eight species of parasites were collected. The nematodes were the 40.5% of the total number of parasites specimens collected. Dichelyne elongatus was the most dominant species. Lobatostoma ringens, Pterinotrematoides mexicanum, Corynosoma australe, D. elongatus, and Caligus haemulonis showed a positive correlation between the host's total length and parasite prevalence and abundance. The monogenean P. mexicanum had differences in the prevalence and abundance in relation to sex of the host. The mean diversity in the infracommunities of M. furnieri was H=0.499±0.411, with correlation with the host's total length and without differences in relation to sex of the host. One pair of ectoparasites showed positive covariation, and two pairs of endoparasites showed positive association and covariation between their prevalences and abundances, respectively. Negative association or covariations were not found. The dominance of endoparasites in the croakers parasite infracommunities reinforced the differences found in sciaenids from the South American Pacific Ocean, in which the ectoparasites are dominant.

Scanning and transmission electron microscopy of the tegument of Paranaella luquei Kohn, Baptista-Farias & Cohen, 2000 (Microcotylidae, Monogenea), parasite of a Brazilian catfish, Hypostomus regani

The surface topography and ultrastructure of the tegument of Paranaella luquei Kohn, Baptista-Farias & Cohen, 2000, a microcotylid monogenean parasite from the gills of Hypostomus regani (Ihering, 1905) (Loricariidae) was studied by scanning (SEM) and transmission electron microscopy (TEM). By SEM, it was observed that the tegument presents transversal ridges, forming folds in the ventral and dorsal surfaces and microvillous-like tegumental projections in the anterior and median regions of body. These projections were also observed by TEM. The tegument is made up of a syncytium delimited by apical and basal plasma membranes, containing inclusion bodies and mitochondria, connected to the nucleated region by means of cytoplasmatic processes. The tegumental cells present a well developed nucleus and cytoplasm containing inclusion bodies, similar to those found on the external layer, mitochondria, rough endoplasmatic reticulum and free ribossomes.

Two new species of Nomimoscolex (Cestoda: Proteocephalidea, Monticelliidae) from Gymnotus carapo (Pisces: Gymnotiformes) in Argentina

Nomimoscolex guillermoi n. sp. and N. dechambrieri n. sp. are described from the gymnotiform fish Gymnotus carapo from Argentina. The new species are placed into Nomimoscolex based on the cortical position of the vitelline follicles, and medullary position of the testes, ovary, and uterus. Both species were compared to the 13 species considered valid in the genus. The combination of features distinguishing N. guillermoi from N. dechambrieri is (1) the position of the vagina to cirrus pouch (anterior or posterior vs always anterior respectively), (2) the total number of testes (41-85 vs 108-130 respectively), (3) the distribution of the vitelline follicles (arranged in dorso-lateral and ventro-lateral bands vs lateral bands respectively), (4) the length of the uteroduct (ending 58% vs 35% from posterior margin of mature proglottis respectively), and (5) the presence of gland cells in the scolex (unicellular glands in the apical region and the external margin of suckers vs the presence of unicellular glands in the apex and other grouped in a cluster medially to the suckers respectively).

In vivo binding of the Cry11Bb toxin of Bacillus thuringiensis subsp. medellin to the midgut of mosquito larvae (Diptera: Culicidae)

Bacillus thuringiensis subsp. medellin produces numerous proteins among which 94 kDa known as Cry11Bb, has mosquitocidal activity. The mode of action of the Cry11 proteins has been described as similar to those of the Cry1 toxins, nevertheless, the mechanism of action is still not clear. In this study we investigated the in vivo binding of the Cry11Bb toxin to the midgut of the insect species Anopheles albimanus, Aedes aegypti, and Culex quinquefasciatus by immunohistochemical analysis. Spodoptera frugiperda was included as negative control. The Cry11Bb protein was detected on the apical microvilli of the midgut epithelial cells, mostly on the posterior midgut and gastric caeca of the three mosquito species. Additionally, the toxin was detected in the Malpighian tubules of An. albimanus, Ae. aegypti, Cx. quinquefasciatus, and in the basal membrane of the epithelial cells of Ae. aegypti midgut. No toxin accumulation was observed in the peritrophic membrane of any of the mosquito species studied. These results confirm that the primary site of action of the Cry11 toxins is the apical membrane of the midgut epithelial cells of mosquito larvae.

Pintomyia (Pifanomyia) paleotownsendi, a new sand fly from the Miocene amber of Dominican Republic (Diptera: Psychodidae: Phlebotominae)

Phlebotominae includes some vector species, mainly that of leishmaniases, with a very old host-parasite relationship. Some species fossils of this subfamily have been recently described and this paper presents the description of a new sand fly Pintomyia (Pifanomyia) paleotownsendi sp. nov in amber. The gonostyle present four spines, being one apical, one external superior implanted close to the apical third, one external inferior in the middle of the structure and one internal implanted in the basal third. This disposition of the spines may separate the new species from others in the sub genus.

Description of Lutzomyia (Lutzomyia) falquetoi sp. nov. (Diptera: Psychodidae, Phlebotominae) a new species from the state of Espírito Santo, Brazil

Lutzomyia (Lutzomyia) falquetoi, sp. nov. (Diptera: Psychodidae, Phlebotominae) is described from the state of Espírito Santo, Brazil. This new species belongs to the series longipalpis and is easily distinguished from the other members of this taxon by the presence of five well-developed spines and a pre-apical spiniform bristle on the gonostyle as well as nine bristles on the basal tuft of the gonocoxite.

Comparative recognition by human IgG antibodies of recombinant proteins representing three asexual erythrocytic stage vaccine candidates of Plasmodium vivax

In previous immuno-epidemiological studies of the naturally acquired antibody responses to merozoite surface protein-1 (MSP-1) of Plasmodium vivax, we had evidence that the responses to distinct erythrocytic stage antigens could be differentially regulated. The present study was designed to compare the antibody response to three asexual erythrocytic stage antigens vaccine candidates of P. vivax. Recombinant proteins representing the 19 kDa C-terminal region of MSP-1(PvMSP19), apical membrane antigen n-1 ectodomain (PvAMA-1), and the region II of duffy binding protein (PvDBP-RII) were compared in their ability to bind to IgG antibodies of serum samples collected from 220 individuals from the state of Pará, in the North of Brazil. During patent infection with P. vivax, the frequency of individuals with IgG antibodies to PvMSP1(19), PvAMA-1, and PvDBP-RII were 95, 72.7, and 44.5% respectively. Although the frequency of responders to PvDBP-RII was lower, this frequency increased in individuals following multiple malarial infections. Individually, the specific antibody levels did not decline significantly nine months after treatment, except to PvMSP1(19). Our results further confirm a complex regulation of the immune response to distinct blood stage antigens. The reason for that is presently unknown but it may contribute to the high risk of re-infection in individuals living in the endemic areas.

Phlebotomine fauna (Diptera: Psychodidae) and species abundance in an endemic area of American cutaneous leishmaniasis in southeastern Minas Gerais, Brazil

This study was undertaken to identify the phlebotomine fauna and species abundance in domiciliary and peridomiciliary (hen-house and guava-tree) environments, on a lake shore, a cultivated area of coffee and banana, and a forested area of Conceição da Aparecida municipality, southeastern the state of Minas Gerais, to provide information for the control and epidemiological surveillance of leishmaniasis in this area. The captures were carried out monthly between May 2001 and November 2002, with automatic light and Shannon traps. A total of 1444 sand flies were captured, 951 (76.5%) with automatic light traps and 493 (23.5%) with the Shannon trap. Thirteen species were captured, the most frequent being Nyssomyia whitmani (62.7%), Migonemyia migonei (21.4%), Pintomyia fischeri (6.9%), and Evandromyia lenti (3.6%). Species abundance was determined using the automatic light traps installed in the six environments. The most abundant species according to the standardized index of species abundance were Ny. whitmani (1.0) and Mg. migonei (0.82). In view of the dominance of these two species, known vectors of cutaneous leishmaniasis in other Brazilian areas, their participation in the transmission of the disease in this county is suggested. The diversity and evenness indexes in the domicile were the lowest due to the high frequency (83%) of Ny. whitmani. The capture of Lutzomyia longipalpis, rarely recorded in the south-eastern and southern regions of Minas Gerais, is also noteworthy.

Morphological study of the eggs and nymphs of Triatoma dimidiata (Latreille, 1811) observed by light and scanning electron microscopy (Hemiptera: Reduviidae: Triatominae)

Eggs and nymphs of Triatoma dimidiata were described using both light and scanning electron microscopy. The egg body and operculum have an exochorion formed by irregular juxtaposed polygonal cells; these cells are without sculpture and the majority of them are hexagonal in shape. The five instars of T. dimidiatacan be distinguished from each other by characteristics of the pre, meso and metanotum. The number of setiferous tubercles increases progressively among instars. The sulcus stridulatorium of 1st instar nymphs is amorphous, showing median parallel grooves; from the 2nd instar on the sulcus is, progressively, elongate, deep and posteriorly pointed with stretched parallel grooves. All instars have a trichobothrium on the apical 1/3 of segment II of the antenna. The opening of the Brindley's gland is on the mesopleura. Fifth instar nymphs have an apical ctenidium on the ventral surface of the fore tibia. Dorsal glabrous patches are found on the lateral 1/3 of abdomen. Bright oval patches are found on the ventral median line of the abdomen, from segment IV-VI; 1st instar nymphs lack these patches. Abdominal dorsal plates are present from the 1st-5th instars; the 1st instar also contains a rectangular plate in segment IX. From the 2nd instar on, variably-shaped plates are present on segments VII to IX. Morphometric data were also obtained and proved to be useful for distinguishing T. dimidiata instars.