''Tetramorium atratulum'' is a rare workerless socially parasitic ant from the

Palaearctic The Palearctic or Palaearctic is a biogeographic realm of the Earth, the largest of eight. Confined almost entirely to the Eastern Hemisphere, it stretches across Europe and Asia, north of the foothills of the Himalayas, and North Africa. Th ...

region, which has even been introduced together with its host in North America. This extreme

inquiline In zoology, an inquiline (from Latin ''inquilinus'', "lodger" or "tenant") is an animal that lives commensally in the nest, burrow, or dwelling place of an animal of another species. For example, some organisms, such as insects, may live in the ...

is represented only by female and pupoid type male individuals, whose

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

and anatomy indicate a highly specialized level of parasitism. The body of males is depigmentated, the cuticle is thin, the

petiole Petiole may refer to: *Petiole (botany), the stalk of a leaf, attaching the blade to the stem *Petiole (insect anatomy) In entomology, petiole is the technical term for the narrow waist of some hymenopteran insects, especially ants, bees, and ...

and postpetiole are widely connected, and degenerate

mandibles In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...

palp Pedipalps (commonly shortened to palps or palpi) are the secondary pair of forward appendages among chelicerates – a group of arthropods including spiders, scorpions, horseshoe crabs, and sea spiders. The pedipalps are lateral to the chelicera ...

s, and antennae are observed. Female wing venation is reduced and the occipital region is narrowed. Mature females are typically

physogastric Physogastrism or physogastry is a characteristic of certain arthropods (mostly insects and mites), where the abdomen is greatly enlarged and membranous. The most common examples are the "queens" of certain species of eusocial insects such as termit ...

and found in queenless host nests. Since, unlike many other obligate social parasites, ''T. atratulum'' is never known to coexist with the host colony's fertile queen, every ''T. atratulum''–''Tetramorium'' sp. colony is doomed to survive only the lifespan of the youngest ''Tetramorium'' sp. workers. Thus, the parasitic queen has very limited scope for producing alates to secure the next generation, as this time span is often only 2–3 years or fewer. As a result, even within its well-established range, ''T. atratulum'' is very scarce, with only a tiny proportion of ''Tetramorium'' sp. colonies playing host to this parasite.

Distribution

Its distribution is local over Eurosiberia and eastern parts of

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

, broadly following that of its hosts. It is present but local in southern parts of

Great Britain Great Britain is an island in the North Atlantic Ocean off the north-west coast of continental Europe, consisting of the countries England, Scotland, and Wales. With an area of , it is the largest of the British Isles, the List of European ...

, having first been discovered in the UK by H. St. J. K. Donisthorpe and W. C. Crawley on July 23, 1912, in the

New Forest The New Forest is one of the largest remaining tracts of unenclosed pasture land, heathland and forest in Southern England, covering southwest Hampshire and southeast Wiltshire. It was proclaimed a royal forest by William the Conqueror, featu ...

Hosts

Although ''T. atratulum'' was reported previously mainly in ''

Tetramorium caespitum ''Tetramorium caespitum'', also known as the red pavement ant, is a species of Myrmicine ant native to Europe, Morocco, and western Asia, but now found on many other continents as a tramp species. Etymology The species is commonly known as the ...

'' and '' T. impurum'' nests, and was recently found in a nest of '' T. immigrans'' (species within the ''Tetramorium caespitum''/''impurum'' complex), it was also recorded from

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. ...

(Italy) from a nontypical low altitude (300 m) in a nest of '' T. diomedeum'', which is a member of the ''

Tetramorium ferox ''Tetramorium'' is a genus of ants in the subfamily Myrmicinae that includes more than 520 species. These ants are also known as pavement ants. Taxonomy and phylogeny ''Tetramorium'' was first described by Gustav Mayr in 1855 in the same publi ...

'' complex. Future clarification of the complicated taxonomic composition of the ''Tetramorium caespitum''/''impurum'' complex will probably enlarge the number of known host ant species parasitized by ''T. atratulum''. The only report about '' T. chefketi'' as a host of ''T. atratulum'' was given by Schulz & Sanetra (2002) as an amendment of the identified material published by Heinze (1987) from

Tavşanlı Tavşanlı is a city in Kütahya Province in the Aegean region of Turkey. It is the seat of Tavşanlı District.

(Turkey,

Kütahya Kütahya (; historically, Cotyaeum or Kotyaion; Ancient Greek, Greek: Κοτύαιον) is a city in western Turkey which lies on the Porsuk River, at 969 metres above sea level. It is the seat of Kütahya Province and Kütahya District. In 19 ...

district). ''

Tetramorium moravicum ''Tetramorium'' is a genus of ants in the subfamily Myrmicinae that includes more than 520 species. These ants are also known as pavement ants. Taxonomy and phylogeny ''Tetramorium'' was first described by Gustav Mayr in 1855 in the same publi ...

'' was also mentioned in Sanetra & Buschinger (2000) as a possible host of ''T. atratulum'', but without any additional data and references.

References

* * *

External links

* {{Taxonbar, from=Q308865 atratulum Hymenoptera of Europe Hymenoptera of North America Insects described in 1852