Use of biometrical characters of cyst for intra-specific and inter-specific variation within the genus Artemia (Crustacea: Anostraca) Patricio De los Rios*1& Alireza Asem2 1) Escuela de Ciencias Ambientales, Facultad de Recursos Naturales, Universidad Católica de Temuco, Casilla 15-D, Temuco, CHILE 2) Artemia & Aquatic Animals Research Institute, Urmia University, PO-Box 165, Urmia, IRAN.   Summary: The brine shrimp Artemia is an organism of great economical importance in the aquaculture industry with a wide distribution all over the world and close 600 reported sites. The genus Artemia shows a wild variation of ecological effects on its biological processes. The laboratory examinations can prove the effect of salinity and temperature on survival, growth and reproductive characters of Artemia. As well as, Ionic composition of the habitat can produce ecological isolation and can lead to morphological and biometrical variation. All these evidences show that ecological speciation is the main mechanism in Artemia speciation. Biometrical study of Artemia cyst show high variation among different species and between different populations of same species. Also it was proved that ecological factor can change biometrical characters of cyst. Biometrical characterizations of Artemia cyst can be used as one of the most important factors in the study of Artemia populations and species particularity; meanwhile these characters can be used as economical index. For example, typically high hatching efficiency is possible due to the small diameter of cysts (high number per gram), therefore small diameter of cysts show someway high quality of cysts. By the way, the interaction between genetic and environmental factors can determine and explain variation in the range of cyst diameter in Artemia.   Home