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.

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.

Myxobolus absonus sp. n. (Myxozoa: Myxosporea) Parasitizing Pimelodus maculatus (Siluriformes: Pimelodidae), a South American Freshwater Fish

A new myxoporean species is described from a freshwater fish in Brazil. Myxobolus absonus sp. n. was found infecting Pimelodus maculatus captured in the river Piracicaba, State of São Paulo, Brazil. Cysts were found free in the opercular cavity. The spores are large (length-15.7 ± 1.5 µm, width-10.2 ± 0.7 µm; mean ± S.D.) and oval in shape, with the anterior end slightly pointed. The spore valves are relatively thin, smooth, and asymmetrical in a frontal view. The polar capsules are pyriform in shape, and unequal in size; the largest are 6.4 ± 0.7 µm long and 3.6 ± 0.5 µm wide, while the smallest are 4.2 ± 0.6 µm long and 2.5 ± 0.5 µm wide.

Revision of the genus Beatogordius (Gordiida, Nematomorpha): II. South american species with description of two new species

Seven species of Beatogordius (Nematomorpha) have been reported from South America. A reinvestigation could not reproduce a number of determinations indicated in the literature. B. deshayesi has been a misinterpretation and the status of B. irregularis appears to be very uncertain, because no generic characters could be found. The descriptions of B. alfredi and B. latastei confirm that these species belong to South America only. In B. abaiconus we found adhesive warts anterior of the male cloacal opening. These structures were to date only known from the genus Gordionus. In the posterior end of females from B. alfredi and B. variabilis, short paired rows of bristles were present which had to date only been known from the African species B. equinatus. Two new species, B. funis and B. palustre could be added to the genus.

Enterobius vermicularis: ancient DNA from north and south American human coprolites

A molecular paleoparasitological diagnostic approach was developed for Enterobius vermicularis. Ancient DNA was extracted from 27 coprolites from archaeological sites in Chile and USA. Enzymatic amplification of human mtDNA sequences confirmed the human origin. We designed primers specific to the E. vermicularis 5S ribosomal RNA spacer region and they allowed reproducible polymerase chain reaction identification of ancient material. We suggested that the paleoparasitological microscopic identification could accompany molecular diagnosis, which also opens the possibility of sequence analysis to understand parasite-host evolution.

Eimeria lepidosirenis n.sp. (Apicomplexa:Eimeriidae) of the South American lungfish Lepidosiren paradoxa (Osteichthyes:Dipnoi) from Amazonian Brazil

The mature oocysts of Eimeria lepidosirenis n.sp. are described in faeces removed from the lower region of the intestine of a single specimen of the South American lungfish Lepidosiren paradoxa, from Belém, state of Pará, Amazonian Brazil. Oocysts with endogenous sporulation: spherical to slightly subspherical, 30.8 × 30.3 µm (28.1 × 25.9 -33.3 × 31.8), shape-index (ratio length/width) 1.0, n = 25. Oocyst wall a very thin, single layer approximately 0.74 µm thick, smooth, colourless, with no micropyle and rapidly breaking down to release the sporocysts. Oocyst residuum a bulky ovoid to spherical mass of approximately 20.0 × 15 µm, composed of fine granules and larger globules and enclosed by a very fine membrane: no polar bodies seen. Sporocysts 15.5 × 9.0 µm (14.5 × 8.0 16.0 × 9.0), shape index 1.7 (1.6-1.8), n = 30, ovoid, with one extremity rather pointed and with a very delicate Stieda body but no sub-Stieda body: sporocyst wall a single extremely thin layer with no valves. Sporocyst residuum a spherical to ovoid mass of approximately 5.0 × 4.0 µm, composed of fine granules and small globules and enclosed by a very fine membrane. Sporozoites strongly recurved at their ends and apparently with only a single refractile body. Site of development in the host uncertain: no evidence of endogenous stages was found in fresh scrapings and stained smears of the intestinal epithelium.

South American Coccinellidae (Coleoptera): part X: A systematic revision of Thalassa Mulsant (Hyperaspidinae)

The genus Thalassa Mulsant, 1850 is revised. Its five species are redescribed: T. pentaspilota (Chevrolat, 1853), T. flaviceps Mulsant, 1850, T. similaris Mulsant, 1850, T. montezumae Mulsant, 1850, and T. glauca (Mulsant, 1850). A new species is proposed, Thalassa korschefskyi sp.nov., from Colombia. The species are illustrated and a key to species is also provided. Lectotype of Thalassa reyi Mulsant, 1850 is here designated.

New species of the South American loxandrine genus Metoncidus Bates (Coleoptera, Carabidae)

Two species are added to the previously monotypic genus Metoncidus Bates, 1871 (Carabidae, Loxandrini): M. epiphytus sp. nov. (type locality Peru: Loreto, Cocha Shinguito) and M. gracilus sp. nov. (type locality Peru: Tambopata, Madre de Dios). Information allowing identification of the genus from among other South American carabid genera and a key to adult individuals of Metoncidus species are provided.

Diagnosis and key of the main families and species of South American Coleoptera of forensic importance

The objective of this paper is to provide diagnosis and keys of the families and species, with illustrations of the main groups. A table of all related species recorded from South America is presented, including the substrate in which they were collected and their geographical distribution. The list comprises 221 species included in 15 families, of which 70% of the species are from Brazil. Scarabaeidae is the most diverse family with 121 species, followed by Staphylinidae with 68. Also we provide one database of Coleoptera species associated with carcasses in South America.

Pseudopsis monica sp. nov. from the western Andes, Peru, with a key to the South American species of Pseudopsis Newman (Coleoptera, Staphylinidae, Pseudopsinae)

Pseudopsis Newman, 1834 is a genus of Pseudopsinae with about 46 species distributed worldwide, five of which have been reported for South America. In this paper P. monica sp. nov. is described and illustrated based on specimens collected in Lima, Peru. A key to South American species of Pseudopsis and a catalog are also provided.

Assessment of rubber tree panels under crowns resistant to South American leaf blight

The objective of this work was to assess the performance of panel clones under crowns resistant to South American leaf blight (Microcyclus ulei). The experiment was carried out with 18 panel clones crown-budded with Hevea pauciflora x H. guianensis, in a Xanthic Ferralsol (Oxisol) in Manaus, AM, Brazil. The following parameters were evaluated: dry rubber yield, plant nutritional status, and anatomical and physiological characteristics of the latex vessels. In the first three years of evaluation, the panel clones IAN 2878, IAN 2903, CNS AM 7905, CNS AM 7905 P1, and PB 28/59 showed the highest dry rubber yield potential, while the clones IAN 6158, IAN 6590, and IAN 6515 should not be recommended for crown budding. Higher potassium and copper foliar content in panel clones were associated to an increase in dry rubber yield. The simultaneous evaluation of anatomical and physiological characteristics of latex is fundamental for the selection of panel clones in the Amazon region. Crown budding is an efficient technology for South American leaf blight management in endemic regions.

Translocation of cyanogenic glycosides in rubber tree crown clones resistant to South American leaf blight

The objective of this work was to assess the possible transport of cyanogenic glycosides from leaves of rubber tree crown clones (Hevea spp.) resistant to South American leaf blight to the trunk of the panel clones in which they are grafted. The cyanogenic potential (HCNp) of the crown clones was determined in the trunk bark, at different distances from the cambium, and its gradient was evaluated along the trunk. The correlation between the HCNp of the crown leaves and that of the trunk bark was also evaluated. HCNp determined in leaves showed a wide range variation in the species studied as crown clones, with the lowest values registered in H. nitida clones, and the highest ones in H. rigidifolia. In the trunk bark, the tissue layer nearer the cambium showed higher HCNp values. A positive basipetal gradient was observed along the trunk, i.e., there was an increase in HCNp from the apex toward the base. Although the grafted crowns influence the cyanogenic potential of the trunk bark of panel clones, the absence of correlation between the HCNp of the leaves and trunk bark indicates that the crown is not the main source of the cyanogenic glycosides found in the trunk.

Bleaching of melanin in the epidermis of South American fur seal and its application on enzyme immunohistochemistry

The South American fur seal (Arctocephalus australis) is an amphibious marine mammal distributed along the Atlantic and Pacific coasts of South America. The species is well adjusted to different habitats due to the morphology of its fin-like members and due to some adaptations in their integumentary system. Immunohistochemical studies are very important to evaluate the mechanisms of skin adaptation due the differential expression of the antigens present in the tissue depending of the region of the body surface. However, its strongly pigmented (melanin) epidermis prevents the visualization of the immuno-histochemical chromogens markers. In this study a melanin bleaching method was developed aimed to allow the visualization of the chromogens without interfering in the antigen-antibody affinity for immunohistochemistry. The analysis of PCNA (proliferating cell nuclear antigen) index in the epidermis of A. australis by immunohistochemistry with diaminobenzidine (DAB) as chromogen was used to test the method. The bleaching of the melanin allowed to obtain the cell proliferation index in epidermis and to avoid false positive results without affecting the immunohistochemical results.

Genital morphology of the male South American fur seal (Arctocephalus australis) and biological implications

Male capacity for spreading genes to a great number of descendents and to determine population dynamics depend directly on the genital organs. Morphological studies in pinnipeds are scarce and the functional meaning of some characteristics has never been discussed. We hypothesized that Arctocephalus australis (A. australis) shows morphophysiological adaptations in order to guarantee the perpetuation of the species in the unique annual mating season. Seven males, dead from natural causes, had their genital organs collected and fixed for morphological description. Some features differ from other described mammalian males and are closely related to the biology and reproductive cycle of this species, as the scrotal epidermis, absence of glandular portion in the ductus deferens and spermatogenic epithelium suggest a recrudescent testis period. The corona glandis exhibits a singular arrangement: its erectile border looks like a formation of petals and its association with the os penis gives a "lily-flower" form to this region. We propose the name margo petaliformis to this particular erectile border of the corona glandis because of its similarity to a flower corola. The male genital organs of A. australis show morphological features compatible with adaptation to environment requirements and reproductive efficiency.