Snail Identification

Index

• Native
  • Physids
  • Lymnaeids
• Invasive Species
  • New Zealand Mud Snail
  • Chinese Mystery Snail
  • Clams
  • Asian Clam

Physids

Key identifying features:

• Hold shell opening facing you with whorl pointing up, the shell opening should be on your left (i.e., left-handed shell).
• Small, ranging from 2 to 8 mm in size
• Conical in shape
• Dark brown to green in color

Lymnaeids

Key identifying features:

• Hold shell opening facing you with whorl pointing up, the shell opening should be on your right (i.e., right-handed shell).
• Common in pond habitats.
• Generally pale-yellowish to dark brown in color.
• Spiraled or conical in shape.
• Can be greater than 30 mm in size.

Invasive Species:

New Zealand Mud Snail

Key identifying features

• Hold shell opening facing out with whorl pointing up, the shell opening should be on your right (i.e., right-handed shell)
• Adult snails are often over 3-5 mm in length in Western U.S.
• Operculum (trap door) present
• Usually 5-6 whorls
• Color varies from gray, light to dark brown
• Can be found in the water or on the banks

Chinese Mystery Snail

Key identifying features:

• Hold shell opening facing you with whorl pointing up, the shell opening should be on your right (i.e., right-handed shell).
• Adult snails are often over 5-cm in length, but can be smaller.
• Operculum (trap door) present.
• Typically light to dark olive green.
• Top of whorl of shell may show chipping or weathering.
• Uniform coloring on the shell.

Clams:

Asian Clam

Key identifying features:

• Clam size is 1 to 1.5 inches
• Colors range from yellow-green to light brown or dark olive green to black.
• Shell has concentric rings with weathering or chipping at tip.