Branchiopodataenia n. g. is established for hymenolepidid cestodes characterised by the presence of a specific morphological feature, a latch-like structure in the copulatory part of the vagina. Their life-cycles involve branchiopod crustaceans (Branchiopoda) as intermediate hosts and gulls as definitive hosts. The type-species of the genus, B. anaticapicirra n. sp. from gulls of Chukotka (Chaun lowlands) and Alaska (River Yukon, Cape Barrow), is described. It is established that B. arctowskii (Jarecka & Ostas, 1984) n. comb. (originally Hymenolepis ) has a bipolar distribution and is not endemic to the Antarctic. A description of B. arctowskii from the northern hemisphere and the principal characters of other known species of this genus, B. gvozdevi (Maksimova, 1988) n. comb. (originally Wardium ), B. haldemani (Schiller, 1951) n. comb. (originally Hymenolepis ) and B. pacifica (Spassky & Jurpalova, 1968) n. comb. (originally Wardium ), are included. A key to the species of Branchiopodataenia is also presented.

the type species of the cestode genus Arostrilepis Mas-coma et tenora, 1997, Arostrilepis horrida (linstow, 1901), is redescribed on the basis of the syntype material from the brown rat (Rattus norvegicus) deposited in the collection of the Museum für Naturkunde, Berlin. Arostrilepis horrida (sensu lato), reported from a wide range of rodents throughout the Holarctic region, is shown to be a species complex. the proposed host range and geographical distribution of A. horrida (sensu stricto) are limited to the data reported in the original description. the previously proposed synonymy of A. horrida is examined and the following species are excluded from the list of its synonyms: Hymenolepis procera Janicki, 1904, H. arvicolina cholodkowsky, 1913, H. sciurina cholodkowsky, 1913 and H. mathevossianae Akhumyan, 1946; these are considered species inquirendae. Specimens previously identified as A. horrida from voles from the Asian part of russia are revised and newly collected materials are worked out. two new species, A. macrocirrosa sp. n. and A. tenuicirrosa sp. n., are described. the main differentiating characters used to distinguish Arostrilepis spp. are the form and size of cirrus and its armature as well as the type of arrangement for the testes. the new species can also be distinguished from one another on the basis of sequences of the its2 rrNA gene. the generic diagnosis of Arostrilepis is emended. Hymenolepis neurotrichi rausch, 1962, which had been placed in Arostrilepis by Mas-coma and tenora (1997), does not correspond to the generic diagnosis and is considered a species incertae sedis.

207 SummaryThe cestode fauna in shrews of the genus Sorex from the European region consists of seventeen species. Twelve cestode species have broad Palearctic distributions, three belong to the Western-Asian-European faunistic complex, and only two are endemic to the European zone. Postglacial expansion into the European territory resulted in geographic colonization by sixteen species. The large number of cestode species with transpalearctic ranges, as well as paleontological data indicating a nearly complete faunal turnover for species of Sorex in the Pleistocene, suggests that these parasites are more ancient than the assemblage of contemporary hosts in which they now occur, and thus represent ecological relicts. We suggest that origins of the cestode fauna pre-date those of the modern fauna of its hosts, and that initial formation and radiation occurred not later than the Pliocene. In the current review, we outline testable hypotheses to explore the structure, history and development of this fauna which appears limited to species of Sorex.

Data are presented on the life-cycles and the postembryonal development of four species of Branchiopodataenia Bondarenko & Kontrimavichus, 2004, B. anaticapicirra Bondarenko & Kontrimavichus, 2004, B. arctowskii (Jarecka & Ostas, 1984), B. haldemani (Schiller, 1951) and B. pacifica (Spassky & Jurpalova, 1968), which are specific parasites of gulls. The investigation was carried out in Chukotka (Chaun Bay) between 1971 and 1981 under natural and experimental conditions. Branchiopod crustaceans were exclusive natural and experimental intermediate hosts of all of the species studied; this fact provided additional evidence for the erection of Branchiopodataenia. The metacestodes exhibit a pattern of postembryonal development and a typical larval form, termed a 'cercocyst', which is a modification of a cysticercoid. This modification of the metacestode does not occur in species of Wardium Mayhew, 1925, the genus with which species of Branchiopodataenia had previously been affiliated.

Aploparaksis demshini n. sp. is described from a woodcock Scolopax rusticola L. from different parts of the Palaearctic (Lithuania, Karelia, the Urals, Primorskiy Kray). It differs from the most similar species A. belopolskajae Bondarenko, 1988, a parasite of snipes Gallinago spp., in the form and length of the rostellar hooks and the smaller cirrus, and from two other similar species, A. clavata Spasskaya, 1966 and A. schilleri Webster, 1955, by having an embryophore with polar thickenings and a spindle-shaped cirrus. The life-cycle of the parasite was studied under experimental conditions. The metacestodes were commonly located under the chlorogogenous tissue of the intestine of the earthworms Eisenia foetida(Savigny), Dendrobaena octaedra (Savigny) and E. nordenskioldi(Eisen), and in the wall of the intestine of the enchytraeid Briodrilus arcticus(Bell). The metacestodes exhibit a pattern of postembryonal development typical for the cysticercoid modification termed an 'ovoid diplocyst'.