Virile Crayfish (Faxonius virilis)
Description: Most widespread native stream & lake species; reddish or brownish, blue claws
Max carapace length: 55 mm
Rostrum: Sides straight
Chelae: Whitish wart-like tubercules, no black bands at tips
Carapace: Narrow areola between branchio-cardiac grooves
Abdomen: Paired brown spots on each segment
Copulatory stylets: Elongate
Calico Crayfish (Faxonius immunis)
Description: Native pond, slow stream & burrowing species; mottled with irregular light median band
Max carapace length: 49 mm
Rostrum: Sides convex
Chelae: Slender, with a notch and tooth midway
Carapace: Narrow areola
Copulatory stylets: Curved
Northern Clearwater Crayfish (Faxonius propinquus)
Description: Small, native, stream & lake species; active in daylight
Max carapace length: 35 mm
Rostrum: Blade-like ridge or carina
Chelae: Smooth, S-shaped
Abdomen: Broad dark dorsal band
Copulatory stylets: Stubby
Allegheny Crayfish (Faxonius obscurus)
Description: Small non-native stream & lake species; rusty to lilac
Max carapace length: 40 mm
Rostrum: Similar to O. propinquus, rostral carina absent
Carapace: Dark crescent at back
Abdomen: Without prominent dark band
Copulatory stylets: With distinctive right-angled shoulder
Rusty Crayfish (Faxonius rusticus)
Description: Large non-native stream & lake species; boldly active in daylight
Max carapace length: 51 mm
Rostrum: Margins slightly concave
Chelae: S-shaped, large gap
Carapace: Often with rusty “thumbprints” on sides
Copulatory stylets: Elongate
Spinycheek Crayfish (Faxonius limosus)
Description: Large potential stream species, spreading westward from Quebec; strongly mottled & speckled
Max carapace length: 59 mm
Carapace: Prominent spines on sides of head
Abdomen: Narrow bars across abdominal segments
Copulatory stylets: Stubby
Devil Crayfish (Lacunicambarus diogenes)
Description: Large native burrower; brown
Max carapace length: 55 mm
Rostrum: Rounded
Carapace: Areola closed at midline
Copulatory stylets: Broad with small hooked tip – all Cambarus species are hooked
Digger Crayfish (Creaserinus fodiens)
Description: Small native burrower; mottled
Max carapace length: 39 mm
Carapace: Rounded rostrum, areola closed, grooves faded posteriorly (detail)
Chelae: With tuft of seta at hinge, deep notch at base of movable dactyl
Copulatory stylets: Hooked, closed at tip
“Common” Crayfish (Cambarus bartonii)
Description: Small native stream & lake species; uniformly brown/olive or reddish
Max carapace length: 39 mm
Rostrum: Short, squarish
Chelae: Only one row of tubercles on inner edge of palm
Copulatory stylets: Short, hooked, open at tip
Big Water Crayfish (Cambarus robustus)
Description: Big native stream species with large claws; brown/olive or reddish
Max carapace length: 57 mm
Chelae: Palms concave, two well-developed rows of tubercles of equal size on inner edge of palm
Copulatory stylets: Hooked, open at tip
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