chemical symmetry in life

[Magidin Viso Monica-IND]

Hello, I don't know where I got the information that there are some 
arthropods that have d-aminoacids instead of l-aminoacids (as almost any 
living thing does), does anyone know if this information is correct? I am 
confused since the arthropods are not a very distant group from the rest 
of the animals or invertebrates, as to have this big basic difference. 
	Thanks,	
		Monica Magidin
		monica at unamvm1.dgsca.unam.mx