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Nectogalini shrews in Central Europe: fossil record, taxonomy, range dynamics.
Pažitková, Barbora ; Horáček, Ivan (advisor) ; Farková, Lucie (referee)
History of shrew clades composing the tribe Nectogalini (including the European genus Neomys) is only poorly comprehended, both due to fragmentarity of their fossil record and incompatibility of the discrimination criteria applied in extant taxa with actual character availability in fossil material. Thus, the presented study started with a thorough biometric reexamination of extant taxa (144 ind. of N. fodiens and N. milleri, 45 ind. ofAsiatic forms) with aid of 217 metric variables and establishing a series of discrimination criteria applicable to fragmentary fossil record. Using it, I analyzed 112 fossil items available from MN15 to Q4 sites of Czech Republic and Slovakia. A rich sample from the present glacial cycle (MIS 5b to Recent) demonstrated that both N. fodiens and N. milleri colonized the region of Central Europe either in earlier stages of Vistulian glacial, in early post-LGM glacial and throughout whole Holocene (though their distribution patterns were perhaps mostly mosaic in both species). The items from the late Biharian (Q2) and the earliest Middle Pleistocene (Q3) were found to represent a single clade characterized by relatively broad phenotype variation. This form, belonging clearly to the genus Neomys, was coidentified with Neomys newtoni Hinton, 1911. The pattern of its...
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Genus Neomys (Mammalia, Eulipotyphla, Soricomorpha): history and range dynamics.
Pažitková, Barbora ; Horáček, Ivan (advisor) ; Vohralík, Vladimír (referee)
Based on numerous literary sources, the thesis reviews current knowledge of history and range dynamics of the genus Neomys, an indexing element of the west Palearctic mammal fauna. It provides a list of fossil records attributed to the extant genus Neomys and extinct clades composing the European records of tribe Nectogalini, and a survey of hypotheses on their phylogenetic relations. Particular attention is given to the genus Asoriculus which is generally considered as an ancestor of the Quaternary radiation of the clade represented in Europe with genera Nesiotites, Neomys and Macroneomys. The transition from Asoriculus to Neomys is expected to appear during the Q1 stage of the Early Pleistocene, more records identified as fossil species of the latter genus are reported from terminal stage of the Early Pleistocene (Q2). Nevertheless, their relations to extant species were not analysed and past history of the extant European taxa (fodiens, anomalus, milleri) and their range dynamics is despite of molecular data generally unclear. This fact reflects both scarcity of the fossil record and uncertainties regarding patterns of phenotype variation in particular species, their discrimination criteria and orientation of corresponding phylogenetic morphoclines. In these regards, the thesis pays special...
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