Virile Crayfish (Faxonius virilis)

Virile crayfish, https://onnaturemagazine.com/crayfish-guide.html

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

Calico crayfish, https://onnaturemagazine.com/crayfish-guide.html

Northern Clearwater Crayfish (Faxonius propinquus)

Northern clearwater crayfish, https://onnaturemagazine.com/crayfish-guide.html

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

Allegheny crayfish, https://onnaturemagazine.com/crayfish-guide.html

Rusty Crayfish (Faxonius rusticus)

Rusty crayfish, https://onnaturemagazine.com/crayfish-guide.html

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

Spiny crayfish, https://onnaturemagazine.com/crayfish-guide.html

Devil Crayfish (Lacunicambarus diogenes)

Devil crayfish, https://onnaturemagazine.com/crayfish-guide.html

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

Digger crayfish, https://onnaturemagazine.com/crayfish-guide.html

“Common” Crayfish (Cambarus bartonii)

Common crayfish, https://onnaturemagazine.com/crayfish-guide.html

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

Big water crayfish, https://onnaturemagazine.com/crayfish-guide.html

Resources

Rusty crayfish is here to stay, ON Nature, Fall 2015, Earth Watch