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   » » Wiki: Asoriculus
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Asoriculus is an extinct of terrestrial shrews in the subfamily (red-toothed shrews) and tribe , native to Europe (including the islands of Corsica, Sardinia and Sicily) and North Africa, from the (from around 6 million years ago) until the late (likely the late 1st millennium BC). The genus is closely related and possibly ancestral to the also recently-extinct ( Nesiotites), with their closest living relative being the ( Soriculus nigrescens).


Taxonomy and evolution
The number of valid species in the genus is uncertain and subject to dispute. The best known species of Asoriculus, Asoriculus gibberodon, was widespread in Europe from the Late (, MN13, from around 7.2-5.3 million years ago) to the Early Pleistocene, and was also present in and the during the .Storch, G., Qiu, Zh., and Zazhigin, V.S. 1998. Fossil history of shrews in Asia, p. 92-1. In Wójcik, J.M. and Wolsan, M. (eds.), Evolution of shrews. Mammal Research Institute Polish Academy of Sciences, Białowieża. The youngest records of the species date to the end of the Early Pleistocene approximately 846,000 ± 57,000 years ago in the Iberian Peninsula. Another larger species, A. thenii, is sometimes also recognised in the Early Pleistocene of Europe. The species Asoriculus maghrebiensis is known from the Pliocene-Pleistocene boundary (c. 2.5 million years ago) of Morocco in North Africa, making it the only known member of Soricinae to have been native to the African continent.

Insular species are known from the islands of ( A. burgioi Late -Early Pleistocene), and - including A. corsicanus (Late Pliocene-Early Pleistocene) and A. similis (Early Pleistocene-/). Asoriculus is closely related and likely ancestral to the genus , known from the from the to the Holocene, whose species have sometimes been included in Asoriculus. The Asoriculus species A. corsicanus and A. similis were formerly included in Nesiotites in its original circumscription, though they are usually no longer treated as part of the genus.

Based on DNA from Nesiotites, the closest living relative of Asoriculus is considered to be the terrestrial ( ), belonging to a of terrestrial nectogaline shrews primarily known from Asia, also including the genera and , rather than related to the nectogaline water shrews ( , and ). A analysis suggests that Himalayan shrews and Balearic shrews genetically diverged approximately 6.44 million years ago.

Phylogeny of Nectogalini based on DNA and morphological characters after Bover et al. (2018).

The Sardinian-Coriscan species A. similis appears to have survived into the Holocene, when it became extinct sometime after human settlement of the islands, with remains apparently being found in and aged archaeological sites in Sardinia. Studies in the 1990s suggested that Asoriculus became extinct on Corsica between 393 and 151 BC during the or Roman period.


Description
The skulls of fossil shews are generally only known from fragments of the and sometimes the nasal-palate region due to the thinness of the rest of the skull bones. A relatively well preserved skull, one of only a handful known for fossil shrews, of Asoriculus gibberodon from the Pliocene of Jradzor, Armenia, is overall closest in morphology to those of its closest living relatives Soriculus and Episoriculus. The skull has four antemolars (the teeth situated between the incisor and the fourth tooth) in each side of the upper jaw, as in the aforementioned genera. The skull of Asoriculus gibberodon differs from Soriculus and Episoriculus in having the lachrymal foramen (an opening of the skull) placed more forward () and higher up () on the skull.

A. gibberodon has been estimated to weigh approximately . The insular species of Asoriculus are substantially larger than A. gibberodon and most other species of Nectogalini, with A. burgioi estimated to weigh and A. similis , which has been cited as an example of .


Ecology
Although some authors have argued for an aquatic ecology based its previously assumed close relationship with Neomys water shrews, the fact that its closest relatives are terrestrial and that its inner ear morphology is closer to those of terrestrial shrews than aquatic shrews suggests a terrestrial lifestyle for Asoriculus. Asoriculus gibberodon has been suggested to have had a preference for humid, vegetated environments near water, though some authors have suggested that it also inhabited arid environments. It is suggested to have used high-pitched clicks to echolocate in order to orientate itself when in dense vegetation, like living shrews.

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