Periclimenaeus

Periclimenaeus
Periclimenaeus hecate
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Malacostraca
Order:	Decapoda
Suborder:	Pleocyemata
Infraorder:	Caridea
Family:	Palaemonidae
Genus:	Periclimenaeus Borradaile, 1915 [1]
Type species
Coralliocaris tridendatus Borradaile, 1915[2]

Periclimenaeus is a genus of decapod crustaceans of the family Palaemonidae which is part of the infraorder Caridea. The genus was named by the English carcinologist Lancelot Alexander Borradaile in 1915. He set out the distinguishing features of the genus as:

Body rather stout, cephalothorax deep, a good deal compressed, abdomen greatly curved Thorax without dorsal swelling. Rostrum rather short, compressed, toothed above only. Outer antennular flagellum not deeply cleft. Antennal scale of good breadth. Mandible without palp. Second maxilliped without podopalp. Third maxilliped narrow, with vestigial arthrobranch.

— L.A. Borradaile, ^[2]

Pericimaenaeus robustus is known only from the type specimen which was collected off Amirante Islands by the Western Indian Ocean Expeditions of Prof. J. Stanley Gardiner and described in 1915 and again in 1917 by Borradaile, it was re-described by Dr A.J. "Sandy" Bruce of the Queensland Museum in 2005.^[3]

Biological notes

Periclimenaeus consists of number of species of small shrimps classified in the subfamily Pontoniinae. They occur mainly in tropical seas, especially in and around coral reefs. Periclimanaeus shrimps live in association with a variety of hosts, mostly sponges and ascidian tunicates, where they normally live in the hosts' internal cavities as pairs formed of a male and a female. Characteristics of the genus include the presence of grossly unequal chelae on the second pair of walking legs, the larger of which has a conspicuous molar process on the seventh and terminal segment of the leg, which sits opposite a depression on the fixed finger, this is used to produce sound, a feature which is convergent with similar structures in the related genus Coralliocaris and in some unrelated genera of snapping shrimps from the family Alpheidae.^[4]

Species

Periclimenaeus is the genus in the Palaemonidae with the second highest number of species with their distribution centred on the Indo-West Pacific region where there are 60 or so species with a further 14 identified so far in the Atlantic and eastern Pacific. The first species to be described was described from specimens caught in the Torres Strait by HMS Alert during 1881-82. These specimens were described by Edward J. Miers as Coralliocaris tridendatus, this was then assigned to Periclimenaeus as P. tridentatus after Borradaile named the genus.^[5]

The following species are currently recognised:^[6]

References