Gergana P. Vasileva

Paranoplocephala aquatica n. sp. (Cestoda, Anoplocephalidae) from Arvicola terrestris and Ondatra zibethica (Rodentia), with redescriptions and comments on related species

Paranoplocephala aquatica n. sp. is described from Arvicola terrestris and Ondatra zibethica (Rodentia, Cricetidae) in Bulgaria. The new species is characterised by a band-like strobila, a uterus forming a fine reticulate structure in the early stages of development, numerous testes (approximately 92) situated mainly aporally to the ovary in both the median and the aporal lateral fields, few testes positioned anterior to the ovary and genital ducts, the prominent asymmetrical situation of the female organs, the length of the vagina c. 0.65–0.68 of the length of the cirrus-sac, and the external seminal vesicle covered by a cellular sleeve. The new species is distinguished from P. ondatrae, P. macrocephala, P. dasymidis and P. sciuri. The specimens from O. zibethica reported as P. ondatrae by Tenora & Murai (1980) and as Aprostatandrya macrocephala by Spasskii et al. (1951) are believed to belong to P. aquatica. The type-series of P. ondatrae and P. macrocephala are redescribed and figured; metric data and an illustration of the holotype of P. sciuri are presented. The genus Paranoplocephala sensu Tenora et al. (1986) is regarded as a heterogeneous group because of the two patterns of uterine development in the species studied. Taxonomic criteria used for distinguishing the genera Andrya and Paranoplocephala, and some criteria applicable at the species level, are discussed.

Records of cysticercoids of Fimbriarioides tadornae Maksimova, 1976 and Branchiopodataenia gvozdevi (Maksimova, 1988) (Cyclophyllidea, Hymenolepididae) from brine shrimps at the Mediterranean coasts of Spain and France, with a key to cestodes from Artemia spp. from the Western Mediterranean

Cysticercoids of two cestode species isolated from brine shrimps from the Mediterranean coasts of Spain and France are described. Fimbriarioides tadornae Maksimova, 1976 (adults known as parasites of Tadorna tadorna) was recorded from Artemia parthenogenetica and A. franciscana from Spain (Bras del Port and River Ebro Delta, respectively), and from A. franciscana from Aigues-Mortes, France (new geographical record). Branchiopodataenia gvozdevi (Maksimova, 1988) (adults known as parasites of Larus genei) was recorded from A. parthenogenetica (Bras del Port, Spain), A. salina (San Pedro del Pinatar, Spain) and A. franciscana (River Ebro Delta, Spain); this is the first record of the species in Europe. An illustrated key to cysticercoids of 12 cestode species from Artemia spp. from the Western Mediterranean is proposed.

Larval helminths in the invasive American brine shrimp Artemia franciscana throughout its annual cycle

One of the best examples of rapid displacement of native species by an invader is the eradication of native Artemia salina and A. parthenogenetica in the Mediterranean by the introduced American A. franciscana. Previous studies based on sampling from limited time periods suggest that the success of the American species as a competitor may be due partly to different parasite burden, since native Artemia spp. have high cestode infection rates regulating their density. The aim of this study is to test the hypothesis that the helminth infection in A. franciscana in its invasive range is low throughout its annual life cycle. Samples of A. franciscana were collected every second month from La Tapa saltern (Andalusia) during one year. Five helminth species were recorded: cestodes Flamingolepis liguloides, F. flamingo, Gynandrotaenia stammeri (all flamingo parasites), Eurycestusavoceti (a shorebird parasite) and larval spirurids of the Acuariinae (the first record of nematodes in Artemia). The overall infection rate was low, with total prevalence 5.9% and prevalence of individual parasite species between 0.2 and 3.2%. The mean abundance of helminths was 0.005–0.155 (av. 0.068), 5–13 times lower than in native congeners. Waterbird counts indicate that the low infection rates cannot be explained by lack of definitive hosts. The results are consistent with the hypothesis that helminths have no regulating effect on the invasive brine shrimp in the Mediterranean. The replacement of the native populations by the invader can be partially explained by a competition mediated by parasites/predators through a differential impact on host fitness.

Participation of metanauplii and juvenile individuals of Artemia parthenogenetica (Branchiopoda) in the circulation of avian cestodes

Adult crustaceans of the genus Artemia (brine shrimps) are intermediate hosts in the life cycle of cestode species parasitic in aquatic birds as their definitive hosts. However, there are no data on the role of larval and juvenile brine shrimps in the transmission of avian helminth parasites. In order to examine the possible role of early developmental stages (nauplii, metanauplii and juveniles) of Artemia for the circulation of avian cestodes, the natural cestode infection in the population of Artemia parthenogenetica from La Mata Lagoon, Mediterranean coast of Spain, was studied. Metacestodes (cysticercoids) of four cestode species were recorded in adult brine shrimps: Flamingolepis liguloides and Flamingolepis flamingo (hymenolepidids parasitic in flamingos), Confluaria podicipina (a hymenolepidid species parasitic in grebes) and Eurycestus avoceti (a dilepidid species parasitic in avocets, stilts, plovers and, to a lesser extent, in flamingos). No cysticercoids were found in nauplii. Two species, F. liguloides and F. flamingo, were found in metanauplii and juvenile brine shrimps. Only 36.3% of the cysticercoids of F. liguloides occurred in adult brine shrimps; the remaining 63.7% were parasitic in metanauplii (39.6%) and juveniles (24.1%). Similarly, the metacestodes of F. flamingo were also distributed among various age groups: in adults (44.4% of cysticercoids), juveniles (27.8%) and metanauplii (27.8%). These results indicate that the early developmental stages of Artemia have an important role for the circulation of certain parasite species. No cysticercoids of C. podicipina and E. avoceti were recorded in larval and juvenile brine shrimps. The selective infestation of larval brine shrimps with flamingo parasites is probably associated with the feeding behaviour of definitive hosts, which are filtering predators; in contrast, grebes and waders pick brine shrimps individually one by one. The possible underlying mechanism for selective infestation of metanauplii and adults by certain cestode species is associated with the size of parasite eggs, allowing only cestode species with small eggs to be ingested by larval brine shrimps.

Helminth parasites of Artemia franciscana (Crustacea: Branchiopoda) in the Great Salt Lake, Utah: first data from the native range of this invader of European wetlands

The present study is the first survey on the role of Artemia franciscana Kellogg as intermediate host of helminth parasites in its native geographical range in North America (previous studies have recorded nine cestode and one nematode species from this host in its invasive habitats in the Western Mediterranean). Samples of Artemia franciscana were collected from four sites in the Great Salt Lake (GSL), Utah, across several months (June-September 2009). A. franciscana serves as intermediate host of five helminth species in this lake. Four of them are cestodes: three hymenolepidids, i.e. Confluaria podicipina (Szymanski, 1905) (adults parasitic in grebes), Hymenolepis (sensu lato) californicus Young, 1950 (adults parasitic in gulls), Wardium sp. (definitive host unknown, probably charadriiform birds), and one dilepidid, Fuhrmannolepis averini Spassky et Yurpalova, 1967 (adults parasitic in phalaropes). In addition, an unidentified nematode of the family Acuariidae was recorded. Confluaria podicipina is the most prevalent and abundant parasite at all sampling sites, followed by H. (s. l.) californicus. The species composition of the parasites and the spatial variations in their prevalence and abundance reflect the abundance and distribution of aquatic birds serving as their definitive hosts. The temporal dynamics of the overall helminth infections exhibits the highest prevalence in the last month of study at each site (August or September). This native population of A. franciscana from GSL is characterised with higher prevalence, intensity and abundance of the overall cestode infection compared to the introduced populations of this species in the Palaearctic Region. The values of the infection descriptors in the native population of A. franciscana are slightly lower or in some cases similar to those of the Palaearctic species Artemia parthenogenetica Barigozzi (diploid populations) and Artemia salina (Linnaeus) in their native habitats.

Palaearctic species of the genus Confluaria Ablasov (Cestoda, Hymenolepididae): a redescription and synonymy of C. capillaris (Rudolphi, 1810)

The types of Confluaria capillaris (Rudolphi, 1810) from Podiceps auritus in (?) Germany and the types of C. capillaroides (Fuhrmann, 1906) from Podiceps dominicus in Brazil are redescribed. C. capillaroides is recognised as a junior synonym of C. capillaris (new synonymy). Data on specimens of the same species from P. cristatus and P. grisegena in Bulgaria are also presented. The previous records of the two nominal species are critically analysed in view of the present redescriptions. The host range of C. capillaris includes only grebes of the genus Podiceps, i.e. P. auritus, P. cristatus, P. grisegena, P. dominicus and P. nigricollis; the records in other hosts (Gaviiformes, Charadriiformes and Passeriformes) are considered erroneous or doubtful. The geographical range includes Europe, Central Asia and northern South America.

Redescription of Chimaerula leonovi (Belogurov & Zueva, 1968) n. comb. (Cestoda, Dilepididae)

Chimaerula leonovi (Belogurov & Zueva, 1968) n. comb. (syns Liga leonovi, Himantaurus leonovi), a parasite of Charadrius spp. in the Palaearctic, is redescribed on the basis of specimens from C. alexandrinus (Aves, Charadriiformes, Charadriidae) from Bulgaria (new geographical record). The new material differs from the original description in some metrical characters: the general measurements of the strobila and the number of proglottides, and measurements of the scolex, rostellar sheath, cirrus-sac and copulatory vagina. The generic diagnosis of Chimaerula Bona, 1994 is amended in order to conform with the morphology of C. leonovi.

Redescription and new records of Mackoja podirufi (Macko, 1962), with an amended diagnosis of Mackoja Kornyushin, 1983 (Cestoda, Hymenolepididae).

Mackoja podirufi (Macko, 1962) [synonyms Echinocotyle podirufi Macko, 1962; Podicipitilepis laticauda of Korpaczewska, 1974] is recorded from grebes Tachybaptus ruficollis and Podiceps nigricollis in Bulgaria (new geographical record) and from T. ruficollis in Germany (new geographical record). The species is redescribed on the basis of specimens from Bulgaria and Germany plus paratypes from Slovakia. In contrast to the original description, an external seminal vesicle and a cirrus-stylet are observed, while an accessory sac is absent. The diagnosis of the monotypic genus Mackoja Kornyushin, 1983 is amended. Mackoja is considered to be similar to the genus Podicipitilepis Yamaguti, 1956, with the type-species P. laticauda Yamaguti, 1956, described from T. ruficollis in Japan. A hypothesis is proposed recognising M. podirufi and P. laticauda as geographical vicariants.

Phylogeny of hymenolepidid cestodes (Cestoda: Cyclophyllidea) from mammalian hosts based on partial 28S rDNA, with focus on parasites from shrews

The aims of the study are to enrich the partial 28S rDNA dataset for hymenolepidids by adding new sequences for species parasitic in the genera Sorex, Neomys and Crocidura (Soricidae) and to propose a new hypothesis for the relationships among mammalian hymenolepidids. New sequences were obtained for Coronacanthus integrus, C. magnihamatus, C. omissus, C. vassilevi, Ditestolepis diaphana, Lineolepis scutigera, Spasskylepis ovaluteri, Staphylocystis tiara, S. furcata, S. uncinata, Vaucherilepis trichophorus and Neoskrjabinolepis sp. The phylogenetic analysis (based on 56 taxa) confirmed the major clades identified by Haukisalmi et al. (Zool Scr 39:631–641, 2010) based on analysis of 31 species: Ditestolepis clade, Hymenolepis clade, Rodentolepis clade and Arostrilepis clade; however, the support was weak for the early divergent lineages of the tree and for the Arostrilepis clade. Novelties revealed include the molecular evidence for the monophyly of Coronacanthus, the non-monophyletic status of Staphylocystis and the polyphyly of Staphylocystoides. The analysis has confirmed the monophyly of Hymenolepis, the monophyly of hymenolepidids from glirids, the position of Pararodentolepis and Nomadolepis as sister taxa, the polyphyly of Rodentolepis, the position of Neoskrjabinolepis and Lineolepis as sister taxa, and the close relationship among the genera with the entire reduction of rostellar apparatus. Resolved monophyletic groups are supported by the structure of the rostellar apparatus. The diversification of the Ditestolepis clade is associated with soricids. The composition of the other major clades suggests multiple evolutionary events of host switching, including between different host orders. The life cycles of Coronacanthus and Vaucherilepis are recognised as secondarily aquatic as these taxa are nested in terrestrial groups.

Redescription of Diporotaenia colymbi Spasskaya, Spassky et Borgarenko, 1971 (Cestoda, Cyclophyllidea, Schistotaeniidae) and amended diagnoses of Diporotaenia Spasskaya, Spassky et Borgarenko, 1971 and Diporotaeniinae Ryzhikov et Tolkacheva, 1975

Diporotaenia colymbi Spasskaya, Spassky et Borgarenko, 1971 (Cestoda, Cyclophyllidea, Schistotaeniidae) is redescribed from Tachybaptus ruficollis (L.) in Turkmenistan. An amended generic diagnosis of Diporotaenia Spasskaya, Spassky et Borgarenko, 1971 is proposed. The taxonomy of Schistotaeniidae Johri, 1959 and the generic composition of its subfamilies, Schistotaeniinae Johri, 1959 and Diporotaeniinae Ryzhikov et Tolkacheva, 1975, are discussed. The genera Ryjikovilepis Gulyaev et Tolkacheva, 1987, Isezhia Gulyaev et Konyaev, 2004, Mircia Konyaev et Gulyaev, 2006 and Decarabia Konyaev et Gulyaev, 2005 are considered as members of the subfamily Diporotaeniinae. An amended diagnosis of the latter subfamily is proposed.