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Eurasian Insectivores and Tree Shrews:
Status Survey and Conservation Action Plan
Published 1995
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Chapter 2
The Insectivora of Eurasia
2.1 Introduction
Insectivores are among the most numerous and widespread small
mammals of the Eurasian region. Their abundance, diversity and ecological
role as key small predators has long been recognised by ecologists, and
been the subject of a large number of field projects throughout the region.
Many research efforts have, however, been hampered by inadequate means
of detecting, observing or following these small animals in their natural
environment. Recent advances such as the application of miniature radio
transmitters should help overcome many of these problems and it is anticipated
that much valuable ecological data will be forthcoming as a result of increased
usage of these techniques.
A second problem which is frequently encountered when sifting through literature on these species is taxonomic confusion. Many species and subspecies still await investigation and confirmation of taxonomic affiliations. Once again, however, recent advances and applications of various biochemical analyses have helped unravel many of the greyer areas of classification. It is expected that these applications, when even more widely applied, will result in further changes to the taxonomy of many species.
For these reasons, it is important to adopt an approach for this Action Plan that is representative of the current status of each species, but which also reflects the growing efforts that are under way to untangle the taxonomic confusion of many groups. This is especially the case when dealing with the Family Soricidae (shrews). Every effort has been made to ensure that the following information is as up-to-date as possible; however, further studies, such as those described above, will inevitably result in some changes to the following accounts.
2.2 Taxonomic Classification -
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The taxonomic classification of the Insectivora has been turbulent and confusing for a considerable number of years. At one stage the Order served as a convenient
"dumping ground" for other primitive forms of insecteating mammals. A common arrangement at one time was to divide the Insectivora into two suborders: the Lipotyphla (with the living families Erinaceidae, Solenodontidae, Nesophontidae, Tenrecidae, Chrysochloridae, Soricidae, and Taipidae), and the Menotyphla, with the families Macroscelididae and Tupaiidae.
Van Valen (1967) considered the Order Insectivora to be restricted to the families Tupaiidae, Macroscelididae, Cynocephalidae (now in the order Dermoptera), Erinaceidae, Talpidae, Nesophontidae, and Soricidae. The families Tenrecidae, Solenodontidae, and Chrysochloridae, were placed in a separate order Deltatheridia. Eisenberg (1981) also united the Tenrecidae and Chrysochloridae in a separate order, the Tenrecomorpha.
In a more recent review, McKenna (1975) elevated the Insectivora to the rank of a grandorder containing two orders: the Erinaceomorpha, with the family Erinaceidae; and the Soricomorpha, with the living families Talpidae, Nesophontidae, Soricidae, Solenodontidae, Tenrecidae, and Chrysochloridae. The Macroscelididae were placed in a separate order - the Macroscelidea which, together with the order Lagomorpha, was put in the grandorder Anagalidia. Still another grandorder, the Archonta was considered to include the orders Scandentia (with the family Tupaiidae), Dermoptera, Chiroptera, and Primates. A modified version of this arrangement was suggested by Novacek (1986), who ranked the Insectivora as a superorder, with the Lipotyphla being the only living order, containing two suborders: the Erinaceomorpha for the Erinaceidae, and the Soricomorpha for the superfamilies Tenrecoidea and Soricoidea (Walker, 1991).
A consensus of current thought on these matters, as expressed by Yates (1984), was that the Insectivora should still be regarded as an order but one that contained only the Lipotyphlan families (including the Erinaceidae) and that the Tupaiidae and Macroscelididae are not closely related to this group and should be placed in separate orders. This broad formula is adopted for the current Action Plan. On a finer level, the recent taxonomic reviews by Hutterer (1993) and Wilson (1993) are followed in this document to describe the nomenclature for Insectivora and Scandentia, respectively.
2.3 Species Accounts - Return to Top of Page | Table of contents
In this section, details are presented on insectivore species in Eurasia. Coverage includes 19 species of hedgehog, 126 shrew species and 35 species of mole. Standard species accounts are given for each species. These include notes on the species' taxonomic nomenclature, a brief physical description of each species, together with notes on its distribution, habitat preferences and ecology, where known. The "IUCN Category of Threat" is also given, using the latest categories and criteria adopted in 1995 (see Box 2.1 and Appendix Ill).
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A taxon is Extinct when there is no reasonable doubt that the last individual
has died. Extinct in the Wild (EW) A taxon is Extinct in the Wild when it is known only to survive in cultivation, in captivity or as a naturalised population (or populations) well outside the past range. A taxon is presumed extinct in the wild when exhaustive surveys in known and/or expected habitat, at appropriate times (diurnal, seasonal, annual), throughout its historic range have failed to record an individual. Surveys should be over a time frame appropriate to thetaxon's life cycle and life form. Critically Endangered (CR) A taxon is Critically Endangered when it is facing an extremely high risk of extinction in the wild in the immediate future, as defined by any of the criteria A to E outlined in Appendix Ill. Endangered (EN) A taxon is Endangered when it is not Critically Endangered but is facing a very high risk of extinction in the wild in the near future, as defined by any of the criteria A to E (see Appendix III). Vulnerable (VU) A taxon is Vulnerable when it is not Critically Endangered or Endangered but is facing a high risk of extinction in the wild in the medium-term future, as defined by any of the criteria A to D (Appendix III). Lower Risk (LR) A taxon is Lower Risk when it has been evaluated and does not satisfy the criteria for any of the categories Critically Endangered, Endangered or Vulnerable. Taxa included in the Lower Risk category can be separated into three sub-categories:
Data Deficient (DD) A taxon is Data Deficient when there is inadequate information to make a direct, or indirect, assessment of its risk of extinction based on its distribution and/or population status. A taxon in this category may be well studied, and its biology well known, but appropriate data on abundance and/or distribution islacking. Data Deficient Is therefore not a category of threat or Lower Risk. Listing of taxa in this category indicates that more information is required and acknowledges the possibility that future research will show that threatened classification is appropriate. It is important to make positive use of whatever data are available, In many cases great care should be exercised in choosing between DD and threatened status. If the range of a taxon is suspected to be relatively circumscribed, if a considerable period of time has elapsed since the last record of the taxon, threatened status may well be justified. Not Evaluated (NE) A taxon is Not Evaluated when it is has not yet been assessed against the criteria.
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