First Data on the Contact Zone and Hybridization between the Cryptic Species of Shrews Sorex araneus and S. satunini (Eulipotyphla, Mammalia)

For the first time, based on sequence variation of microsatellite loci and the mtDNA cytb gene fragment, population genetic structure of the common shrew and Caucasian shrew in their contact zone was investigated. It was demonstrated that, although there was no complete reproductive isolation between the species under consideration, the gene flow was considerably limited. These data testify to the established reliable reproductive barriers between the common shrew and Caucasian shrew.

Insights on the host associations and geographic distribution of Hymenolepis folkertsi (Cestoda: Hymenolepididae) among rodents across temperate latitudes of North America

Synoptic data and an understanding of helminth parasite diversity among diverse rodent assemblages across temperate latitudes of North America remain remarkably incomplete. Renewed attention to comprehensive survey and inventory to establish the structure of biodiverse faunas is essential in providing indicators and proxies for identifying the outcomes of accelerating change linked to climate warming and anthropogenic forcing. Subsequent to the description of Hymenolepis folkertsi in the oldfield mouse, Peromyscus polionotus, additional specimens of hymenolepidids were collected or discovered in archived museum repositories from multiple species of deer mice (Peromyscus maniculatus, Peromyscus leucopus), the golden mouse (Ochrotomys nuttalli), chipmunks (Tamias striatus, Tamias amoenus), the 13-lined ground squirrel (Ictidomys tridecemlineatus), and tree squirrels (Sciurus carolinensis, Sciurus niger) from disjunct localities in the USA spanning southern Georgia, Virginia, Pennsylvania, Connecticut, the Upper Peninsula of Michigan, Wisconsin, and central Idaho. Specimens were largely consistent morphologically with the original description of H. folkertsi. Initial DNA sequence data, from a portion of the mitochondrial NADH dehydrogenase subunit 1, demonstrated intraspecific variation among three apparently geographically isolated populations attributed to H. folkertsi (uncorrected genetic distances of 2.7 % (Idaho and Michigan), 2.4 % (Virginia + Pennsylvania and Michigan), and 1.89 % (VA + PA and ID). Geography rather than host association explains the distribution and occurrence of H. folkertsi, and host colonization among deer mice, chipmunks, and other sciurids within regional sites is indicated. Genetic divergence revealed across localities for H. folkertsi suggests historically isolated populations, consistent with extended evolutionary and biogeographic trajectories among hymenolepidids and species of Peromyscus and Tamias in North America. Field inventory, that revealed these parasite populations, substantially alters our understanding of the distribution of diversity and provides insights about the nature of the complex relationships that serve to determine cestode faunas in rodents.

[Pararodentolepis gen. n., a new genus of cestodes from rodents, with the description of P. sinistra sp. n. (Cyclophyllidea: Hymenolepididae)]

A new cestode genus and speies with armed scolex, Pararodentolepis sinistra gen. et sp. n. (Cyclophyllidea: Hymenolepididae), is described ex brown rat Rattus norvegicus Berkentheut, 1769 from the western Siberia. The differential diagnosis is also given.

[Relictolepis gen. n.--a new cestode genus (Cyclophyllidea: Hymenolepididae) from rodents of the Russian Far East and the description of R. feodorovi sp. n]

A new cestode genus and species Relictolepis feodorovi gen. et sp. n. having armed scolex is described ex Clethrionomis rufocanus Sundevall, 1846 (Rodentia, Microtinae) from the Russian Far East.