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Craniometric study of the common shrew (Sorex araneus L. 1758) from different localities and chromosomal races across Germany and Europe

100%

Stefen C.

Acta Theriologica

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2013

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tom 58

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nr 3

A total of 440 skulls of common shrews, Sorex araneus, from Germany and Europe (Croatia, Hungary, Austria, and Norway) were studied. The material represented six chromosomal races (Ulm, Laska, Drnholec, Mooswald, Jütland, and Abisko) assignable to the Western European and Northern European karyotypic groups. The race of a few samples was not determined. Twenty-one linear measurements were taken on skulls and mandibles and used in this study. Pearson correlations and multiple linear regressions were used to see the relationship of the cranial variables to altitude, latitude, the chromosomal race, and the geographic location. The results from the tested samples differed; the most negative correlations to latitude were found in the samples assigned to the Western European karyotypic group (WEK), the least negative ones in the samples of the Ulm race. These results indicate the converse of Bergmann's rule. But taking into consideration all the samples of the different karyotypic groups across Europe, the correlations to latitude included positive ones, which would indicate that Sorex follows Bergmann's rule in some of the variables. The studied material of different karyotypic groups could not be differentiated in discriminant analyses. The separation of the studied races within the WEK alone was slightly better, but about 30 % of ungrouped cases remained. Only the separation of the regional samples within one chromosomal race revealed better results but was still very different between the races. This indicates that within the races, regional differences might be strong enough for a separation of the samples and that within a karyotypic group, and even more so across karyotypic groups, regional differences conceal racial differences.

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The castorid Steneofiber from NW Germany and its implications for the taxonomy of Miocene beavers

63%

Mors T., Stefen C.

Acta Palaeontologica Polonica

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2010

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tom 55

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nr 2

189-198

Craniodental remains of a medium−sized beaver from the early middle Miocene of Hambach (MN 5) in the Lower Rhine Basin of northwestern Germany are described and assigned to Steneofiber depereti. The relatively rich material (6 mandibles and 56 isolated teeth) was collected from a single locality, Hambach 6C, and comprises specimens representing juvenile to very old individuals. This makes it possible to assess the morphologic and metric variability of a single population of Steneofiber depereti. Metrically, the mandibular tooth rows compare favorably in size to those of three subspecies described from the Loire Basin in France: Steneofiber depereti janvieri, Steneofiber d. caliodorensis, and Steneofiber d. depereti. Therefore in our opinion, division into subspecies cannot be applied to S. depereti in general. The difference in size between the smaller beaver from Hambach and the contemporaneous larger S. d. carnutense from the Loire Basin is remarkable. The taxonomy of early middle Miocene medium−sized castorids, referred to Steneofiber depereti, Steneofiber subpyrenaicus, and Chalicomys jaegeri is discussed. The presence of the derived beaver C. jaegeri in MN 4 to MN 6 is questioned and assignment to Steneofiber suggested. The occasional appearance of single C. jaegeri features in S. depereti supports the existence of a European lineage from the Orleanian S. depereti to the Vallesian C. jaegeri. The taxonomic status of S. subpyrenaicus remains unresolved.

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Differences in the microhabitat preferences of Neomys fodiens (Pennant 1771) and Neomys anomalus Cabrera, 1907 in Saxony, Germany

51%

Keckel M. R., Ansorge H., Stefen C.

Acta Theriologica

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2014

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tom 59

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nr 4

The two semi-aquatic shrew species Neomys fodiens and Neomys anomalus are very similar in their ecology and morphology. Thus, they tend to be strong competitors for resources when they occur syntopically in habitats. We analysed the microhabitat selection of both species based on 14 parameters at two study sites in western Saxony (Germany). At the first study site, the results show segregation into different preferred microhabitats. In comparison to N. fodiens, N. anomalus occurred in low distance to the oxbow lake at places with denser herbal cover. Thus, we verified the hypothesis of Rychlik (Acta Theriologica 42:351-388 1997) who assumed differences in microhabitat niches for both shrew species to avoid competition. Furthermore, there was a spatial segregation within N. fodiens depending on their age. While adults occurred close to the water at areas with sparse herb layer, the juveniles and subadults were predominantly captured in some distance to the stream at denser vegetation. We assume that this is the result of different microhabitat preferences in N. fodiens depending on age and not a result of intraspecific antagonism. Moreover, the possibility to build subsurface burrows (and as an equivalent to this, crevice systems resulting of bank fixation with large stones) seems to be the main limiting factor for the occurrence of N. fodiens at the other surveyed site. At this site, no differences in microhabitats were visible between the age classes of N. fodiens.

Ograniczanie wyników

2 Acta Theriologica

1 Acta Palaeontologica Polonica

3 Stefen C.

1 Ansorge H.

1 Keckel M. R.

1 Mors T.

1 2014

1 2013

1 2010

Craniometric study of the common shrew (Sorex araneus L. 1758) from different localities and chromosomal races across Germany and Europe

The castorid Steneofiber from NW Germany and its implications for the taxonomy of Miocene beavers

Differences in the microhabitat preferences of Neomys fodiens (Pennant 1771) and Neomys anomalus Cabrera, 1907 in Saxony, Germany