Temporal variation in prevalence and abundance of metacercariae in the pulmonate snail Lymnaea stagnalis in Chany Lake, West Siberia, Russia: long-term patterns and environmental covariates

Infrapopulations of trematode metacercariae were monitored in the snail Lymnaea stagnalis over 17 yr (1982-1999) at Chany Lake, Novosibirskaya Oblast', Russia. Eighteen trematode species were recorded. Patterns of occurrence varied from 4 species (Echinoparyphium aconiatum, Echinoparyphium recurvatum, Moliniella anceps, and Cotylurus cornutus) that persisted at relatively high prevalence (> 60% of samples) across sites, seasons, and years, to species that were very rare and sporadic in occurrence. The stability of the 4 common species was probably because of their occurrence either in a wide range of definitive hosts or in a host adapted to the extreme abiotic changes that occurred from year to year in these wetlands. The prevalence and mean abundance of C. cornutus were negatively correlated with water level in the wetlands; its prevalence was also correlated with water temperature. The mean abundance of M. anceps was positively correlated with water level. The most probable explanation for the cyclic dynamics of infections of the common species is change in population sizes and densities of definitive and intermediate hosts, which mediated cyclic alterations in water levels.     

Development of the plerocercoid I of Ophiotaenia europaea in reptiles

The existence of a two-host life-cycle in ophiotaeniid proteocephalideans was tested experimentally using Ophiotaenia europaea as a model. Three species of reptiles, Natrix natrix, Natrix tessellata and Lacerta viridis, were fed with experimentally infected copepods containing a large number of infective plerocercoids I. A few plerocercoids, most of which were dead, corresponding morphologically to the plerocercoid II developmental stage of O. europaea, were found encysted in the intestinal wall of N. natrix (8 days p.i.), N. tessellata (5 and 150 days p.i.) and L. viridis (40 days p.i.), while no plerocercoids or adult worms were recovered from their intestines. The results indicate that the infective plerocercoid I of O. europaea cannot undergo further development when ingested directly by the final host (a reptile), and that environmental temperature stimuli cannot initiate a reverse plerocercoid migration to the gut followed by strobilization.     

A quantitative approach to the evaluation of the morphological variability of two echinostomes, Echinostoma miyagawai Ishii, 1932 and E. revolutum (Frölich, 1802), from Europe

A comparative morphometric analysis was conducted on two European species of Echinostoma in order to examine the degree of the variability in the metrical characteristics of the adults and to assess their value in discriminating species. Adult E. miyagawai and E. revolutum, obtained experimentally, were compared using univariate and multivariate statistical analyses of 35 and 25 metrical characters, respectively. All subsets of worms of different ages represented homogeneous samples with respect to their morphometric characteristics; however, univariate analyses revealed significant differences in 22 and 23 variables between the corresponding age subsets of the two species, and it was found that the different allometric growth patterns contribute to this. The variables, body width at the posterior border of the ventral sucker, pharynx length and width, ovary length, testes length and width and length of the pre-ovarian region, exhibited isometric or positive allometric growth in E. miyagawai and negative allometry in E. revolutum. A cluster analysis based on 61 specimens and 25 variables separated E. revolutum and E. miyagawai unambiguously, producing an exact ordering of the specimens with respect to their identity and age. A forward stepwise discriminant analysis identified five variables (body width at the posterior border of ventral sucker, head collar width, length of oesophagus, width of ventral sucker and length of the pre-ovarian region) which yielded a 100% accurate classification of the two species. We suggest, therefore, that the morphometric characteristics of the adult worms should be used in studies attempting the identification of species or isolates of Echinostoma spp. More comparative data need to be gathered in order that the species boundaries within the revolutum group be defined more accurately.     

Spalacina yanchevi n. g., n. sp. (Nematoda: Heligmonellidae) from the lesser mole rat Spalax leucodon (Rodentia: Spalacidae)

Spalacina n. g. (Heligmonellidae, Nippostrongylinae) is erected for S. yanchevi n. sp. (type-species) [syns Heligmonina nevoi of Genov & Janchev (1982) and Genov (1984)] from Spalax leucodon (Spalacidae) and two other species from spalacid rodents previously considered as members of Heligmonina Baylis, 1928: S. spalacis (Sharpilo, 1973) n. comb. and S. nevoi (Wertheim & Durette-Desset, 1975) n. comb. The new genus belongs to the subfamily Nippostrongylinae and is closely related to the genus Heligmonina from which it can be distinguished by a greater angle of rotation of the synlophe, the absence of a gradient on the ventral ridges and a weakly developed right dorsal ridge. The zoogeographical distribution of Spalacina spp. is associated with that of Palaearctic spalacids. S. yanchevi differs from S. spalacis and S. nevoi in the number and size of the ridges, the distance between the extremities of the rays 6 and 8, the degree of reduction of the dorsal ray and the length of the spicules.     

Polystoma macrocnemis n. sp. (Monogenea: Polystomatidae) from the Iranian longlegged wood frog Rana macrocnemis (Ranidae) in Turkey

Polystoma macrocnemis n. sp. (Polystomatidae) is described from the urinary bladder of Rana macrocnemis (Ranidae) in Turkey. Its general morphology is similar to that of other members of the genus, but it is distinguished from closely related species by numerical parameters of the hamuli and also by its host species and geographical range.     

A common registration-to-publication automated pipeline for nomenclatural acts for higher plants (International Plant Names Index,IPNI), fungi (Index Fungorum,MycoBank) and animals (ZooBank)

Collaborative effort among four lead indexes of taxon names and nomenclatural acts ( International Plant Name Index (IPNI), Index Fungorum, MycoBank and ZooBank) and the journals PhytoKeys, MycoKeys and ZooKeys to create an automated, pre-publication, registration workflow, based on a server-to-server, XML request/response model. The registration model for ZooBank uses the TaxPub schema, which is an extension to the Journal Tag Publishing Suite (JATS) of the National Library of Medicine (NLM). The indexing or registration model of IPNI and Index Fungorum will use the Taxonomic Concept Transfer Schema (TCS) as a basic standard for the workflow. Other journals and publishers who intend to implement automated, pre-publication, registration of taxon names and nomenclatural acts can also use the open sample XML formats and links to schemas and relevant information published in the paper.     

Polystoma fuscus n. sp. (Polystomatidae) from the common spadefoot Pelobates fuscus (Pelobatidae) in Bulgaria

Polystoma fuscus n. sp. (Polystomatidae, Polystomatinae) is described from the urinary bladder of Pelobates fuscus (Pelobatidae) in Bulgaria. Its general morphology is similar to that of other members of the genus but distinguished from them by the underdeveloped hamuli similar to the larval hamular primordia. The new species is also differentiated from the members of the genera of the subfamily Polystomatinae described without hamuli.     

Heligmosomoides glareoli Baylis, 1928 (Nematoda: Heligmosomidae): redescription and synonymy

Paratypes of Heligmosomoides glareoli Baylis, 1928 are re-described. Specimens of the same species from Microtus nivalis and Clethrionomys glareolus collected in Bulgaria were also studied. H. tatricus (Erhardova, 1955) Durette-Desset, 1967 is considered a synonym of H. glareoli on the basis of the morphometric characters, synlophe structure and the distribution of their host.