My favorite:
SCP-410Class: Safe
Short excerpt: Description: SCP-410 is a colony of fourteen (14) individual beetles (designated Scarabaeus scriptor by staff coleopterist Dr. ██████ ), each measuring approximately 5cm and possessing a carapace color variation from light blue to deep emerald green. A visual examination reveals nothing distinctive from other members of the genus Scarabaeus with regards to their appearance (number of legs, wings, eyes, etc). Dissection of a single member of the colony by a trained coleopterist showed no discernible anomalies in internal morphology with the exception of a small additional organ (designated the "scriptorgan" by Dr. ██████ ) capable of producing a variety of fluids both caustic and inert. It is worth noting that following the death and dissection of this member of the colony, a "replacement" beetle larvae was seen fourteen (14) days later and grew to full maturity within one month.