pa4210783 freshwater triclad flatworms, girardia tigrina, on black, cecp 2023

planaria triclad girardia tigrina planarian platyhelminthes turbellaria tricladida dugesiidae flatworm worm freshwater aquatic animal north america british columbia close closeup brown black fauna natural detail predator nature wild macro isolated invertebrate creeks streams spings white eyes eyespots flatworms benthic water uncommon unusual flat invasive pa4210783 cecp 2023 backlit darkfield three semi-transparent creeping species native europe japan