''Asoriculus'' is an extinct

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of terrestrial

shrews Shrews (family Soricidae) are small mole-like mammals classified in the order Eulipotyphla. True shrews are not to be confused with treeshrews, otter shrews, elephant shrews, West Indies shrews, or marsupial shrews, which belong to diffe ...

in the subfamily

Soricinae The red-toothed shrews of the subfamily Soricinae are one of three living subfamilies of shrews, along with Crocidurinae (white-toothed shrews) and Myosoricinae (African white-toothed shrews). In addition, the family contains the extinct subfamil ...

(red-toothed shrews) and tribe

Nectogalini Nectogalini is a tribe of Old World shrews within the family Soricidae. As of late 2007, it consisted of six extant genera and 25 species, with some of the latter being further divided into subspecies. Some, but not all members of the tribe are ...

, native to Europe (including the islands of Corsica, Sardinia and Sicily)

West Asia West Asia (also called Western Asia or Southwest Asia) is the westernmost region of Asia. As defined by most academics, UN bodies and other institutions, the subregion consists of Anatolia, the Arabian Peninsula, Iran, Mesopotamia, the Armenian ...

and North Africa, from the

Late Miocene The Late Miocene (also known as Upper Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages. The Tortonian and Messinian stages comprise the Late Miocene sub-epoch, which lasted from 11.63 Ma (million ye ...

(from around 6 million years ago) until the late

Holocene The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene to ...

(likely the late

1st millennium BC File:1st millennium BC.jpg, 400x400px, From top left clockwise: The Parthenon, a former temple in Athens, Greece; Aristotle, Greek philosopher; Gautama Buddha, a spiritual teacher and the founder of Buddhism; Wars of Alexander the Great last from ...

). The genus is closely related and possibly ancestral to the also recently-extinct Balearic shrews (''Nesiotites''), with their closest living relative being the

Himalayan shrew The Himalayan shrew (''Soriculus nigrescens'') is a species of shrew in the subfamily Soricinae (red-toothed shrews) and tribe Nectogalini. It is native to montane forest habitats in the southern Himalayas in Bhutan, China, India, Myanmar, and Ne ...

(''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

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

(

Messinian The Messinian is in the geologic timescale the last age or uppermost stage of the Miocene. It spans the time between 7.246 ± 0.005 Ma and 5.333 ± 0.005 Ma (million years ago). It follows the Tortonian and is followed by the Zanclean, the fir ...

, MN13, from around 7.2-5.3 million years ago) to the

Early Pleistocene The Early Pleistocene is an unofficial epoch (geology), sub-epoch in the international geologic timescale in chronostratigraphy, representing the earliest division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently esti ...

, and was also present in

Anatolia Anatolia (), also known as Asia Minor, is a peninsula in West Asia that makes up the majority of the land area of Turkey. It is the westernmost protrusion of Asia and is geographically bounded by the Mediterranean Sea to the south, the Aegean ...

and the

Caucasus The Caucasus () or Caucasia (), is a region spanning Eastern Europe and Western Asia. It is situated between the Black Sea and the Caspian Sea, comprising parts of Southern Russia, Georgia, Armenia, and Azerbaijan. The Caucasus Mountains, i ...

during the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58 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

Mediterranean The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...

islands of

Sicily Sicily (Italian language, Italian and ), officially the Sicilian Region (), is an island in the central Mediterranean Sea, south of the Italian Peninsula in continental Europe and is one of the 20 regions of Italy, regions of Italy. With 4. ...

(''A. burgioi'' Late

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Corsica Corsica ( , , ; ; ) is an island in the Mediterranean Sea and one of the Regions of France, 18 regions of France. It is the List of islands in the Mediterranean#By area, fourth-largest island in the Mediterranean and lies southeast of the Metro ...

Sardinia Sardinia ( ; ; ) is the Mediterranean islands#By area, second-largest island in the Mediterranean Sea, after Sicily, and one of the Regions of Italy, twenty regions of Italy. It is located west of the Italian Peninsula, north of Tunisia an ...

including ''A. corsicanus'' (Late Pliocene-Early Pleistocene) and ''A. similis'' (Early Pleistocene-

Late Pleistocene The Late Pleistocene is an unofficial Age (geology), age in the international geologic timescale in chronostratigraphy, also known as the Upper Pleistocene from a Stratigraphy, stratigraphic perspective. It is intended to be the fourth division ...

). ''Asoriculus'' is closely related and likely ancestral to the genus ''

Nesiotites ''Nesiotites'' is an extinct genus of large red-toothed shrews belonging to the tribe Nectogalini that inhabited the Balearic Islands from the latest Miocene/Early Pliocene (from around 5.3 million years ago) up until the arrival of humans on the ...

'', known from the

Balearic Islands The Balearic Islands are an archipelago in the western Mediterranean Sea, near the eastern coast of the Iberian Peninsula. The archipelago forms a Provinces of Spain, province and Autonomous communities of Spain, autonomous community of Spain, ...

from the

Early Pliocene Early may refer to: Places in the United States * Early, Iowa, a city * Early, Texas, a city * Early Branch, a stream in Missouri * Early County, Georgia * Fort Early, Georgia, an early 19th century fort Music * Early B, stage name of Jamaican d ...

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

(''

Soriculus ''Soriculus'' is a genus of shrew native to the Himalayas, the adjacent Hengduan Mountains and surrounding areas. There is generally only one recognised species, '' Soriculus nigrescens'', (as other extant species previously assigned to the genus ...

''), belonging to a

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

of terrestrial nectogaline shrews primarily known from Asia, also including the genera ''

Episoriculus ''Episoriculus'' is a genus of shrew in the red-toothed shrew subfamily. Its common is brown-toothed shrew. It has been described as a subgenus to '' Soriculus'' in the past. The genus occurs at a number of locations in Asia, including Nepal and ...

'' and ''

Chodsigoa ''Chodsigoa'' is a genus of shrews in the tribe Nectogalini. Species There are currently ten species classified under the genus ''Chodsigoa'': *Van Sung's shrew (''Chodsigoa caovansunga'') (Lunde, Musser and Son, 2003) *''?Chodsigoa hoffmanni ...

'', rather than related to the nectogaline water shrews (''

Chimarrogale The Asiatic water shrews are the members of the genus ''Chimarrogale''. They are mammals in the subfamily Soricinae of the family Soricidae. They are aquatic, with some species inhabiting streams. The genus contains the following species: * Mala ...

'', ''

Nectogale The elegant water shrew (''Nectogale elegans'') is a species of mammal in the subfamily Soricinae of the family Soricidae. It is the only species within the genus ''Nectogale''. It lives in Sikkim and China China, officially the People ...

'' and ''

Neomys The genus ''Neomys'' is a group of four Eurasian water shrews from the subfamily Soricinae of the family Soricidae. These shrews are found in most of Europe and parts of northern Asia, as well as Turkey and Iran Iran, officially the ...

''). A

molecular clock The molecular clock is a figurative term for a technique that uses the mutation rate of biomolecules to deduce the time in prehistory when two or more life forms diverged. The biomolecular data used for such calculations are usually nucleot ...

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

Mesolithic The Mesolithic (Ancient Greek language, Greek: μέσος, ''mesos'' 'middle' + λίθος, ''lithos'' 'stone') or Middle Stone Age is the Old World archaeological period between the Upper Paleolithic and the Neolithic. The term Epipaleolithic i ...

and

Neolithic The Neolithic or New Stone Age (from Ancient Greek, Greek 'new' and 'stone') is an archaeological period, the final division of the Stone Age in Mesopotamia, Asia, Europe and Africa (c. 10,000 BCE to c. 2,000 BCE). It saw the Neolithic Revo ...

aged archaeological sites in Sardinia. Studies in the 1990s suggested that ''Asoriculus'' became extinct on Corsica between 393 and 151 BC during the

Carthaginian The term Carthaginian ( ) usually refers to the civilisation of ancient Carthage. It may also refer to: * Punic people, the Semitic-speaking people of Carthage * Punic language The Punic language, also called Phoenicio-Punic or Carthaginian, i ...

Roman Roman or Romans most often refers to: *Rome, the capital city of Italy *Ancient Rome, Roman civilization from 8th century BC to 5th century AD *Roman people, the people of Roman civilization *Epistle to the Romans, shortened to Romans, a letter w ...

period.

Description

The skulls of fossil shews are generally only known from fragments of the

maxilla In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxil ...

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

premolar The premolars, also called premolar Tooth (human), teeth, or bicuspids, are transitional teeth located between the Canine tooth, canine and Molar (tooth), molar teeth. In humans, there are two premolars per dental terminology#Quadrant, quadrant in ...

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 (

anteriorly Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. Thi ...

) and higher up (

dorsally Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provi ...

) 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

island gigantism Island gigantism, or insular gigantism, is a biological phenomenon in which the size of an animal species isolated on an island increases dramatically in comparison to its mainland relatives. Island gigantism is one aspect of the more general "is ...

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.

References

{{Taxonbar, from=Q44966006 Miocene first appearances Holocene extinctions Mammal genera