Lanfrediella amphicirrus gen. nov. sp. nov. Nematotaeniidae (Cestoda: Cyclophyllidea), a tapeworm parasite of Rhinella marina (Linnaeus, 1758) (Amphibia: Bufonidae)

The family Nematotaeniidae, tapeworms commonly found in the small intestines of amphibians and reptiles, includes 27 recognised species distributed among four genera: Bitegmen Jones, Cylindrotaenia Jewell, Distoichometra Dickey and Nematotaenia Lühe. The taxonomy of these cestodes is poorly defined, due in part to the difficulties of observing many anatomical traits. This study presents and describes a new genus and species of nematotaeniid parasite found in cane toads (Rhinella marina) from eastern Brazilian Amazonia. The cestodes were collected during the necropsy of 20 hosts captured in the urban area of Belém, Pará. The specimens were fixed and processed for light microscopy, scanning electron microscopy (SEM) and three-dimensional (3D) reconstruction. Samples were also collected for molecular analyses. The specimens presented a cylindrical body, two testes and paruterine organs. However, they could not be allocated to any of the four existing nematotaeniid genera due to the presence of two each of dorsal compact medullary testes, cirri, cirrus pouches, genital pores, ovaries and vitelline glands per mature segment. Lanfrediella amphicirrus gen. nov. sp. nov. is the first nematotaeniid studied using Historesin analysis, SEM and 3D reconstruction, and it is the second taxon for which molecular data have been deposited in GenBank.

Histochemical and ultrastructural studies on the calcareous corpuscles and eggs of taenia taeniaeformis and dipylidium caninum

Calcareous corpuscles were noticed by several previous workers to be present in larval and adult cestodes without knowing their function. However, nothing was mentioned in the available literature about distribution of these corpuscles and their density, structure and composition in different parts of the body of different cestodes. Hence, in the present work, a comparative study of their distribution, density, histochemical and ultrastructural characters in different parts of the body was performed in Taenia taeniaeformis and Dipylidium caninum. Due to the presence of the eggs in their gravid segments, their histochemical and ultrastructural characteristics were also studied. It was found that the size, location and density of the calcareous bodies were different in different body parts of the same and the other cestode. Histochemically, the main component of these corpuscles was calcium; while other constituents as polysaccharides, lipids, protrins and mucopolysaccha-rides were found in their outer rim. Ultrastructurally, they were quite similar in the two studied cestodes and different stages of their development were exhibited. Histochemically, the eggs of both cestodes were similar in their contents. However, some ultrastructural differences have been demonstrated particularly in relation to the size and shape of the rods in the embryophore and the structures in between the embryophore and onchosphere

Contribution of electron microscoopic studies to the biology and classification of parasitic cestodes [review article]

Members of phylum Platyhelminthes are leaf-like or tape-like worms. Class Cestoidea are exclusively parasitic organisms; covered with a nonciliated integument; ciliated epithelium, when present, confined to embryos [onchospheres] hatched from eggs; scolex provided with suckers and frequently hooks for attachment to host tissue; body in most species divided into separate, sexually complete proglottids. Class: Cestoidea: comprises two subclasses: Cestodaria body undivided; only one set of reproductive organs; oncosphere hatching from egg has 10 hooklets. Cestoda: body typically with scolex and series of proglottids,each with one set [rarely 2 sets] of male and female organs; oncosphere typically has 6 hooklets [Beaver et al., 1984]

Examen paleoparasitológico de sedimentos de un sitio arqueológico, Río Mayo, Chubut, Argentina / Paleoparasitological analysis of sediments of an archaeological site, Río Mayo, Chubut, Argentina

En este trabajo, que tiene como objetivo el estudio paleoparasitológico, se analizan sedimentos procedentes del rescate arqueológico de un entierro múltiple en un alero rocoso, cercano a la localidad de Río Mayo, al sudoeste del Chubut. Se obtuvieron sedimentos extraídos de la región pélvica de un esqueleto humano procedente de Patagonia y vinculado al período de contacto europeo-aborigen. Mediante técnicas cuantitativas y cualitativas se registraron huevos de anoplocefálidos y de Trichuris sp. La inspección macroscópica previa de la muestra evidenció fecas de roedor y su examen paleoparasitológico evidenció huevos de anoplocefálidos, Trichuris sp, Capillaria sp y un ascadidido no identificado. Por lo tanto, se advierte la posible contaminación del depósito con parásitos de roedores.

Fauna parasitaria gastrointestinal en polluelos de Pingüino Papua (Pygoscelis papua) encontrados muertos en zona antártica especialmente protegida (ZAEP N°150) / Gastrointestinal parasite fauna of nine gentoo Penguin Chicks (Pygoscelis papua) found dead in an antartic territory protected zone

En el presente trabajo, se comunica la presencia de Streptocara spp (Nematoda: Acuariidae) y de Contracaecum spp (Nematoda: Anisakidae) en estómago; de dos escolex de tenias (Cestoda: Cyclophyllida) y huevos de Tetrabothrium spp (Cestoda: Pseudophyllida) en el intestino de pollos de pingüino Papua encontrados muertos en una zona Antártica protegida.

Registros taxonômicos de cestóides trypanorhyncha/homeacanthoidea em elasmobrânquios coletados na costa do Estado do Paraná, Brasil / Taxonomic reports of trypanorhyncha/homeacanthoidea cestodes in elasmobranchs collected in the coast of the state of Paraná, Brazil

Specimes of elasmobranch fishes, captured in 1998 in the the State of Paraná, Brazil, were parasitized with Trypanorhyncha/Homeacanthoidea cestodes: Carcharhinus signatus with Heteronybelinia yamagutii (Dollfus, 1960) Palm, 1999 and H. nipponica (Yamaguti, 1952) Palm, 1999; Dipturus trachydermus (Krefft & Stehmann, 1975) with Mixonybelinia beveridgei (Palm et al, 1997) Palm, 1999. Details of scolex morphology of the two species of Heteronybelinia that expanded their desciptions were obtained. The known geographical distribution of the species is widened.