african giant snail

achatina achatinidae achatinina achatininae achatininan achatinoidea african ahatina antenna background brazil brazilian brown caucasus disease environment eupulmonata euthyneura euthyneuran food fulica garden gastropod gastropoda gastropods giant green heterobranch heterobranchia house invasive invertebrate lissachatina macro mollusc mollusca molluscs mollusk mucilage nature one shell slimy slug snail spiral wildlife