any member of the subphylum Crustacea (phylum Arthropoda), a group of invertebrate animals consisting of some 45,000 species distributed worldwide. Crabs, lobsters, shrimps, and wood lice are among the best-known crustaceans, but the group also includes an enormous variety of other forms without popular names.
It is thought that infrequent, low-dose users may test positive for Xanax within urine for up to 4 days post-ingestion. Frequent, high-dose users of the drug may test positive for Xanax after a full week post-ingestion via a urinalysis. Results from a urinalysis can be confirmed with technology such as GC/MS.
Benzos vary, however xanax is the shorted acting benzo and will be out of your urine in 48 hours as long as you didnt take like 30mg, which could be deadly. On a side note Valium and stay in your system for 2-3 weeks, not sure why, but it can, it has a very long half life, so if you get drug tested dont take valium.