Thaumasioscolex didelphidis n. gen., n. sp. (Eucestoda: Proteocephalidae) from the black-eared opossum Didelphis marsupialis from Mexico, the first proteocephalidean tapeworm from a mammal.

Thaumasioscolex didelphidis n. gen., n. sp. is described from the intestine of the black-eared opossum Didelphis marsupialis L. (Marsupialia: Didelphidae) from Los Tuxtlas, Veracruz, Mexico. The new genus differs from all proteocephalidean genera in the morphology of the scolex that is formed by 4 well separated lobes each containing 1 noncircular sucker opening laterally inside the exterolateral cavity, a large-sized body (length up to 1 m), a large number of testes, the shape of gravid proglottids that are inversely craspedote (the anterior border of a proglottid overlaps the posterior border of a preceding proglottid), eggs in groups mostly of 4-6 eggs each, and an embryophore bearing digitiform projections on its external surface. This is the first tapeworm of the Proteocephalidea, the members of which were previously reported exclusively from poikilotherm vertebrates (freshwater fishes, amphibians, and reptiles), found in a homoiotherm vertebrate.     

Galaxitaenia toloi n. gen., n. sp. (Eucestoda: Pseudophyllidea) from Galaxias platei (Pisces: Osmeriformes, Galaxiidae), in the Patagonian region of Argentina

Galaxitaenia n. gen. (Eucestoda: Pseudophyllidea) is proposed to accommodate Galaxitaenia toloi n. gen., n. sp. from Galaxias platei, a freshwater fish inhabiting Andean lakes in Argentine Patagonia. Galaxitaenia belongs to the Triaenophoridae because it possesses a marginal genital pore, a ventral uterine pore, and a follicular vitelline gland. The new genus can be distinguished from other triaenophorids by the following combination of characters: a scolex with a prominent rectangular apical disc without hooks, grooves, or indentations; neck present; segments wider than long to quadrangular; testes in 2 lateral fields, often connected anteriorly; cirrus unarmed; an ovary situated posteriorly; a vagina posterior to the cirrus sac; vitelline follicles medullary, in 2 ventral fields forming 2 wings interrupted medially; a uterus saccate to branched; and eggs without operculum. The types, distribution, and density of microtriches were analyzed on the surface of the tegument of scolex, neck, and immature segments. The presence of tumuli were observed on the apical disc of the scolex. Galaxitaenia toloi n. sp. is the first triaenophorid species recorded in a South American freshwater fish and the fourth helminth parasitizing the intestine of G. platei.     

Nomimoscolex pertierrae n. sp. (Eucestoda: Proteocephalidea), a parasite of Pseudoplatystoma corruscans (Siluriformes: Pimelodidae) in Brazil and redescription of N. sudobim Woodland, 1935, a parasite of P. fasciatum

The cestode Nomimoscolex sudobim Woodland, 1935 (Proteocephalidea) is redescribed on the basis of its type-specimens and recently collected material found in the intestine of the 'sudobim' Pseudoplatystoma fasciatum (Siluriformes: Pimelodidae) (type-host), from the Amazon River (near the type-locality). Nomimoscolex pertierrae n. sp. is described from the 'surubi' Pseudoplatystoma corruscans from the Paraná River around Porto Rico. Among fifteen known Nomimoscolex species, only N. sudobim possess a cortical uterus in combination with osmoregulatory canals some distance internal to the proglottis margins, as in N. pertierrae n. sp. N. pertierrae differs from N. sudobim, which exhibits the most similarity with the former species, in the morphology of the scolex, the size and unusual shape of microtriches (slender digitiform) on the internal and marginal regions of the suckers, and in the lower mean number of testes [(114 in N. pertierrae, ranging between 216 (recently collected material) and 240 (type-material) in N. sudobim)]. The material described as N. sudobim by Pavanelli & Rego (1992) from the intestine of P. corruscans is considered to be N. pertierrae. The utility of microtriches as characters for distinguishing between species is demonstrated in the clear differences in the shape of those of N. pertierrae and N. sudobim. The morphology of microtriches warrants more attention in future studies on the taxonomy of proteocephalidean cestodes.     

Nolleria pulicis n. gen., n. sp. (Microsporida: Chytridiopsidae), a microsporidian parasite of the cat flea, Ctenocephalides felis (Siphonaptera: Pulicidae)

A new species of microsporidium, Nolleria pulicis, is described and named here from the cat flea, Ctenocephalides felis. The genus Nolleria is created and placed within the family Chytridiopsidae. The family is slightly modified to accommodate certain features of intracellular development seen in N. pulicis, which is otherwise very similar to other species in the family Chytridiopsidae. Sporulation is described from ultrastructural analysis of infected midgut epithelial cells of adult C. felis. The term "multiple division by vacuolation" is proposed for describing sporogony as it occurs in this species and certain related species of microsporidia. The probable mode of transmission and apparent absence of merogony are discussed.     

Notomegarhynchus navonae n. gen. and n. sp. (Eucestoda: Tetraphyllidea), from skates (Rajidae: Arhynchobatinae) in the southern hemisphere

Notomegarhynchus n. gen. (Eucestoda: Tetraphyllidea) is proposed to accommodate Notomegarhynchus navonae n. gen., n. sp. from Atlantoraja castelnaui in Mar del Plata, Argentina. Notomegarhynchus shetlandicum n. comb. from Bathyraja eatonii and B. maccaini in South Shetlands region, Antarctica, is a second species in the genus. Notomegarhynchus belongs to the Echeneibothriinae within the Phyllobothriidae. It can be distinguished from all other tetraphyllidean genera by the structure of the scolex in form of a massive myzorhynchus consisting of a proscolex and an apical organ, both of which are nonretractable and noninvaginable; in addition, there are 4 pedunculated and nonloculate acetabula. Notomegarhynchus shetlandicum is differentiated from N. navonae particularly in details of acetabular and myzorhynchus morphology, arrangement of testes, and shape of eggs. The inclusion of Notomegarhynchus in the Echeneibothriinae requires emendation of the diagnosis of the subfamily to include taxa possessing postvaginal testes. In addition, new terminology is proposed for distinct regions of the scolex.     

Pirupalkia queulensis n. gen., n.sp. (Digenea: Callodistomidae) in the fish Cilus montti (Pomadasyidae)

A new genus and species of the subfamily Callodistomidae is described. The new genus is named Pirupalkia queulensis n. gen., and was found in the small intestine of the fish Cilus montti. This new genus, compared with other genus of the subfamily differs principally in the distribution of the vitellaria and location of the uterus.     

Ultrastructural studies of Henneguya rhamdia n. sp. (Myxozoa) a parasite from the Amazon teleost fish, Rhamdia quelen (Pimelodidae)

Henneguya rhamdia n. sp. is described in the gill filaments of the teleost fish Rhamdia quelen, collected from the Peixe Boi River, State of Pará, Brazil. This myxosporean produced spherical to ellipsoidal plasmodia, up to 300 microm in diameter, which contained developmental stages, including spores. Several dense bodies up to 2 microm in diameter were observed among the spores. The spore body was ellipsoidal (13.1 microm in length, 5.2 microm in width, and 2.5 microm in thickness) and each of the two valves presented a tapering tail (36.9 microm in length). These valves surrounded the binucleated sporoplasm cell and two equal ellipsoidal polar capsules (4.7 x 1.1 microm), which contained 10-11 (rarely 12) polar filament coils. The sporoplasm contained sporoplasmosomes with a laterally eccentric dense structure with a half-crescent section. Based on the data obtained by electron microscopy and on the host specificity, the spores differed from previously described Henneguya species, mainly in their shape and size, number and arrangement of the polar filament coils, and sporoplasmosome morphology.     

Basipodella harpacticola n.gen., n. sp. (Crustacea,Copepoda)

Several stages of the copepodBasipodella harpacticola n. gen., n. sp., which lives as a parasite on harpacticoid copepods, are described on the basis of four individuals obtained from the Peruvian deep-sea. The taxonomic position of the new species is discussed.     

Eremotyle affixa,n. gen., n. sp., eine neue Protococcale (Chlorophycee)

Ohne ZusammenfassungDie Veröffentlichung dieser Untersuchungen fällt zusammen mit der Feier des 70. Geburtstages Prof. Dr.Franz Ruttners. Der Verf. möchte nicht versäumen, mit seinem Glückwunsch dem Jubilar auch seinen herzlichsten Dank auszusprechen: hat er ihm doch zuerst als Student, später als junger Dozent, endlich als Kollege vielerlei Arten von Belehrung, Anregung und Förderung zu verdanken. Mögen diese Zeilen der Erinnerung an manche gemeinsam verlebte Stunden gewidmet sein!     

Molecular and ultrastructural characterization of Andreanna caspii n. gen., n. sp. (Microsporida: Amblyosporidae), a parasite of Ochlerotatus caspius (Diptera: Culicidae)

A new genus and species of microsporidia, Andreanna caspii n. gen., n. sp. is described from the mosquito, Ochlerotatus caspius (Pallas) based on ultrastructural morphology, developmental characteristics, and comparative sequence analyses of the small subunit (SSU) ribosomal DNA (rDNA). Parasite development is confined to fat body tissue and infected larvae appear swollen with dull white masses within the thorax and abdomen. Meronts have diplokaryotic nuclei and are delineated by a simple plasmalemma contiguous with the host cell cytoplasm. Merogony occurs by synchronous binary division followed by cytokinesis. Diplokaryotic sporonts undergo meiosis and synchronous nuclear division forming sporogonial plasmodia with two, four and eight nuclei enclosed within a persistent sporophorous vesicle. Cytokinesis of sporogonial plasmodia results in the formation of eight uninucleate spores. The episporontal space of early sporonts is filled with a homogeneous accumulation of electron dense granular inclusions and ovoid vesicles of various dimensions, transforming into an interwoven matrix during the initial phase of sporogenesis. Spores are oval, uninucleate and measure 4.8 ± 0.3 × 3.1 ± 0.4 μm (fixed). The spore wall is 260 μm thick with an irregular exospore consisting of two layers (150-170 μm) and a thinner endospore (90-100 μm). The anchoring disk is well developed and is contiguous with a lamellar polaroplast that occupies the anterior third of the spore and possess more narrow lamellae on the posterior end. The polar filament is gradually tapered and arranged in a single row consisting of six coils ranging from 180 to 150 μm in diameter. The posterior vacuole (posterosome) is moderately sized and filled with a matrix of moderate electron density. Phylogenetic analysis of SSU rDNA from A. caspii and 30 other species of microsporidia including 11 genera parasitic in mosquitoes using maximum parsimony, neighbor joining and maximum likelihood methods showed A. caspii to be a sister group to the clade containing all of the Amblyospora species, including Culicospora, Edhazardia and Intrapredatorus, as well as Culicosporella and Hyalinocysta thus providing strong support for establishment of Andreanna as a separate genus.     

A New Ataloderinae (Nematoda: Heteroderidae), Thecavermiculatus gracililancea n. gen., n. sp.

Thecavermiculatus gracililancea n. gen., n . sp. is described from the roots of Festuca myuros L. ("rattail fescue") a range grass in Monterey County, California. Thecavermiculatus females have a slight terminal prominence on which are located the vulva and anus, while its closest relatives, Atalodera and Sherodera, have a large terminal prominence. Furthermore, in T. gracililancea the hatched second-stage juveniles are retained in the female body while Atalodera and Sherodera females retain embryonated eggs.     

Sauertylenchus labiodiscus n. gen., n. sp., from Australia (Nematoda:Tylenchorhynchinae)

Sauertylenchus labiodiscus n. gem, n. sp. is described and illustrated from soil around Rhagodia sp. in Australia. It can be distinguished from the most closely related genus Tylenchorhynchus Cobb, 1913 by the distinctly set-off, rounded, lip region with a conspicuous labial disc, and long thin stylet. The face view and spicules of Sauertylenchus labiodiscus are illustrated with scanning electron micrographs. The subfamilies Tylenchorhynchinae and Merlininae ale discussed.     

Description of Auriculotrema lechneri n. gen., n. sp. (Digenea: Choanocotylidae), a parasite of freshwater turtles (Testudines: Pleurodira: Chelidae) from Queensland,Australia

Auriculotrema lechneri n. gen., n. sp. is described from the small intestine of Emydura krefftii and Elseya latisternum from northern Queensland, Australia. The new species strongly resembles species of Choanocotyle in body shape, ventral incision of the oral sucker, structure of the cirrus sac, and location of the genital pore. The distinctive taxonomic feature is the presence of 2 winglike projections extending beyond the lateral margins of the oral sucker, in contrast to the extremely large, expanded oral sucker diagnostic of Choanocotyle spp. Auriculotrema n. gen. is the second genus included in the formerly monotypic Choanocotylidae Jue Sue and Platt, 1998.     

Auriculostoma astyanace n. gen., n. sp. (Digenea: Allocreadiidae), from the banded astyanax, Astyanax fasciatus (Characiformes: Characidae), from Nicaragua, with a reevaluation of neotropical Crepidostomum spp

Auriculostoma n. gen. (Trematoda: Allocreadiidae) is proposed for Auriculostoma astyanace n. sp. from the intestine of the characid fish Astyanax fasciatus in the Atlantic coastal drainages of Nicaragua. The new genus differs from all papillose allocreadiid genera, except Bunoderella, in possessing 2 pairs of muscular oral papillae (instead of 1 or 3), of which the ventrolateral pair is moderately developed and the dorsolateral papillae are long and auricular. Auriculostoma differs from Bunoderella Schell, 1964, in having lateral vitelline follicles, completely separated or confluent only in the posttesticular region, a uterus limited to the pretesticular region or with a few eggs at the level of the testes, and a long cirrus sac that overlaps the acetabulum or usually reaches posteriorly to the ovarian level. Three other allocreadiid species, all from South American freshwater fishes and each of which had previously been placed in Crepidostomum, are transferred to Auriculostoma based on the presence of the diagnostic muscular oral papillae. These include Crepidostomum platense Szidat, 1954, C. macrorchis Szidat, 1954, and C. stenopteri Ma?é-Garzón and Gascón, 1973. Diagnostic features for Auriculostoma also include mainly pretesticular uterus, lateral vitellaria with variation in posttesticular confluence, and tandem testes. The genus appears to be typically associated with neotropical siluriforms (catfishes) and characiforms (tetras).     

Narcinecotyle longifilamentus n. gen., n. sp. (Monogenea: Hexabothriidae), gill parasite of the numbfish Narcine entemedor (Torpediniformes: Narcinidae) from the Mexican Pacific coast

A new genus and species of Hexabothriidae Price, 1942 is described from specimens infecting the gill of the numbfish Narcine entemedor Jordan and Starks from the Pacific coast of Mexico. In addition to the new taxon described here, species of 8 genera also display symmetrical haptors and have eggs with two polar filaments. However, they differ in the combination of the following features: distal portion of the male copulatory organ tubular, unarmed and proximally dilated confining an internal coiled duct, as well as dorsal origin of haptoral appendix. Based on molecular data derived from 3 loci, the mitochondrial Cytochrome C oxidase subunit 1 as well as the nuclear ribosomal 18S and 28S, the new species was found nested within Hexabothriidae together with the other 4 genera with representatives in GenBank. This is the first species of Hexabothriidae reported from a species of Narcinidae.     

Histopathology in Paulicea lutkeni (Pisces: Pimelodidae) resulting from infections with Megathylacus brooksi and Jauela glandicephalus (Cestoda: Proteocephalidae)

The histopathology in Paulicea lutkeni naturally infected with Megathylacus brooksi and Jauela glandicephalus is described. Megathylacus brooksi attaches to the epithelium of the anterior intestine by means of suckers, resulting in damage to the epithelium, haemorrhages and lymphocyte infiltration. Jauela glandicephalus penetrates through all layers of the intestine. This penetration elicits an intense host-response resulting in the hyperplasy of connective tissue and formation of a nodule surrounding the scolex of the parasite. Lymphocyte infiltration was observed. Concurrent infections were found in some specimens.     

Rhizochrysidopsis vorax,n. gen., n. sp.

Zusammenfassung Die Art ist durch eine bedeutende Variation der Zellgröße, damit auch des Chromatophors und des Kerns ausgezeichnet. Mit steigender Zellgröße nimmt die Zahl der kontraktilen Vakuolen von zwei auf mindestens acht zu. — Unter Umständen erfolgt exzessive animalische Ernährung; es werden auch im Vergleich zum Zellkörper sehr große Algenzellen aufgenommen und verdaut.     

Kamegainema cingulum (Linstow, 1902) n. gen., n. comb. (Nematoda: Dracunculidae), a subcutaneous parasite of cryptobranchids (Amphibia: Caudata)

The monotypic Kamegainema n. gen. is proposed for Filaria cingula, a subcutaneous parasite of cryptobranchids. Examination of female specimens recently collected from the Japanese giant salamander, Andrias japonicus, revealed that it belongs to Dracunculidae. Kamegainema is closest to Protenema Petter and Planelles, 1986, the only other dracunculid genus known from Amphibia, but is readily distinguished by having prominent cuticular bosses. Kamegainema cingulum is redescribed.