horse-leech haemopis sanguisuga floats in water

2010 aid alternative animal annelid background biology black blood bloodsucker bloodsucking body closeup danube delta detail floats haemopis health hermaphrodite hirudinea hirudo hirudotherapy horse horseleech hospital human illness isolated leech leeches macro medical medicinal medicine microbiology nature parasite parasitic romania rumunsko sanguisuga science skin suck sucker therapy treatment water wet white worm