105
Northern Crayfish, Orconectes virilis: Measurements and Ratios: Form II Male
Number Minimum Maximum Mean
Total length 43 37.5 101.0 66.2
Carapace
Total length 43 19.6 51.7 33.4
Postorbital length 43 14.8 40.2 25.6
Aureola
Length 43 6.4 18.4 11.9
Width 43 0.3 1.0 0.6
Chela
Total length 42 11.2 49.0 24.9
Dactyl length 42 7.2 35.4 17.0
Palm length 42 2.6 12.1 6.1
Palm width 42 4.2 18.9 9.3
Finger gap 42 0.0 4.7 1.4
Antenna
Total length 42 31.2 87.9 61.2
Ratios Number Minimum Maximum Mean
Carapace length / Total length 43 0.42 0.87 0.51
Aureola length / Carapace length 43 0.33 0.42 0.36
Aureola length / Aureola width 43 10.6 43.3 22.0
Chela length / Carapace length 41 0.51 1.03 0.73
Dactyl length / Chela length 41 0.63 0.73 0.68
Palm width / Chela length 41 0.26 0.41 0.37
