IDENTIFICATION 



For generic separation of Liraeus and Asellus and for species identifica- 

 tion of Asellus it will be necessary in using this publication to be 

 familiar with the conformation of and the terminology applied to at least 

 certain parts of the external structure of asellids. For confirmation of 

 species identity by reference to the original description or to a complete 

 description given elsewhere, a similar familiarity will be required with 

 regard to most of the remaining body parts. Before discussing the actual 

 technique of specimen examination, it is appropriate therefore to describe 

 briefly the morphology of a typical species. Asellus aommunis has been 

 selected for this purpose. 



Fig. 1. A, dorsal view of male Asellus communis; B, dorsal view 

 of male Liraeus sp. Drawn from preserved specimens. Original, 

 a. = abdomen, h.=head, t.= thorax. 



There are three major body regions, the head, thorax, and abdomen (Fig. 1) 

 The head and abdomen appear unsegmented, whereas the thorax is divided 

 into seven segments. Each region bears a number of appendages projecting 

 either anteriorly, posteriorly, ventrally or laterally. 



