Character	Acroperus harpae	Acroperus angustatus
Denticles on postero-ventral corner of valves	with narrow bases, spaced	with broad bases, saw-like, clustered together
Antenna:		
length	about 1/4 of body length	about 1/5 of body length
length of branches	exopodite much longer than endopodite	branches of same length
seta on basal segment of exopodite	less than 2/3 length of middle segment	as long as middle segment
seta on middle segment of exopodite	1.5 times longer than apical segment	2.5 times longer than apical segment
apical setae of exopodite	one seta much thicker than others	all setae of same thickness
Scrapers 6-7 of limb II	similar to other scrapers	more robust than other scrapers
Limb V exopodite	Incursion between lobes broad, rectangular	incursion between lobes as acute angle
Male postabdomen		
shape	narrowing in distal part	rectangular
postabdominal claw	longer than preanal portion of postabdomen	shorter than preanal portion of postabdomen