|by Brito Capello , 1867|
Atyaephyra is a genus of freshwater shrimp with distribution in the Mediterranean region and the Middle East, east to the Shatt al-Arab , Iraq. One species, Atyaephyra desmarestii , was introduced by humans as a neozoon into large areas of Western and Central Europe.
The genus includes freshwater shrimp with a carapace length between 5 and 8 millimeters, which are translucent whitish or inconspicuously colored and not marked. They have two pairs of spines, the supraorbital and antennal spines, on both sides of the eye opening at the front edge of the carapace . The eyes are well developed and functional (a difference to the related and similar genus Troglocaris ). Only the first two pairs of striding legs of the trunk section (peraeon) have an exopodite, on the remaining three pairs of legs it is completely regressed. In the male, the genital appendage (masculine appendix) on the second of the two pairs of pleopods is long, sub-cylindrical and has numerous spine-shaped bristles. A typical field feature for the Atyaephyra is a long tuft of hair on the tip of the scissor fingers of the first and second peraeopods, which the genus has in common with some relatives (family feature).
Systematics and taxonomy
Félix António de Brito Capello discovered a type of freshwater shrimp near Coimbra in Portugal in 1867, which he described as Atyaephyra rosiana . Arnold Edward Ortmann noticed in 1890 that the Hippolyte desmarestii and Atyaephyra rosiana described by Pierre-Aimé Millet from France as early as 1831 are in fact the same species for which he introduced the name Atyaephyra desmarestii , since they could not be assigned to any of the previously proposed genera. Type species of the genus is therefore Atyaephyra rosiana, a synonym of Atyaephyra desmarestii. 
Thereafter, the systematists were long of the view that the genus Atyaephyra would only include this one species, but for which a number of varieties and subspecies were specified, whose status and delimitation were, however, disputed. It was not until the 2000s that the earlier collective species was split up, mainly through genetic research. Accordingly, the animals of the eastern Mediterranean that were previously included in this species actually belong to a number of other species that are difficult to differentiate according to morphological criteria ( cryptospecies ). The species was initially split into seven new species,  of which one was later synonymous with Atyephyra desmarestii .  However, other cryptic species may exist.
As far as we know in 2014, the genus therefore includes the following species:
- Atyaephyra desmarestii (Millet, 1831) . Western Mediterranean region, from western North Africa via the Iberian Peninsula, southern France and Italy as well as on the islands of Corsica, Sardinia and Sicily. Also introduced into large parts of Western and Central Europe as a neozoon. The Atyaephyra acheronensis Christodoulou et al. probably belongs to this species. 
- Atyaephyra orientalis Bouvier , 1913. South Anatolia, Syria, Israel, Jordan, Iraq. Probably a complex of several cryptospecies that have not yet been differentiated.
- Atyaephyra stankoi Karaman , 1972. Greece.
- Atyaephyra thyamisensis Christodoulou et al., 2012. Greece.
- Atyaephyra strymonensis Christodoulou et al., 2012. Greece.
- Atyaephyra tuerkayi Christodoulou et al., 2012. At first only in the river Nahr Al-Kabir between Syria and Lebanon, later material from other parts of Syria was discovered. 
The demarcation to the eyeless genus Troglocaris, which lives in karst groundwater and cave waters, is morphologically clear, but unclear according to genetic studies. The only species of the genus widespread in France, Troglocaris inermis Fage, 1937, was, according to genetic data, more closely related to Atyaephyra desmarestii than to the other Troglocaris species from the Balkans.  For the species was the (monotypic) genus later Gallo Caris erected. 
- Magdalini Christodoulou, Aglaia Antoniou, Antonios Magoulas, Athanasios Koukouras (2012): Revision of the freshwater genus Atyaephyra (Crustacea, Decapoda, Atyidae) based on morphological and molecular data. ZooKeys 229: 53–110. doi:10.3897/zookeys.229.3919
- J. E. Muñoz, J. E. Raso, A. Rodríguez, J. A. Cuesta (2014): Cryptic speciation of Greek populations of the freshwater shrimp genus Atyaephyra de Brito Capello, 1867 (Crustacea, Decapoda), evidence from mitochondrial DNA. Zootaxa 3790 (3): 401–424. doi:10.11646/zootaxa.3790.3.1
- Magdalini Christodoulou, Paul F. Clark (2016): A new species of shrimp discovered in the Senckenberg collection. Senckenberg. Nature Research Museum 146 (1/2): 40–41.
- Damjan Franjević, Mirjana Kalafatić, Mladen Kerovec, Sanja Gottstein (2010): Phylogeny and evolutionary history of the cave-dwelling atyid shrimp Troglocaris based on sequences of three mtDNA genes. Periodicum Biologorum 112(2): 159–166.
- Boris Sket, Valerija Skakšek (2008): European cave shrimp species (Decapoda: Caridea: Atyidae), redefined after a phylogenetic study; redefinition of some taxa, a new genus and four new Troglocaris species. Zoological Journal of the Linnean Society 155: 786–818.