Wild Wonders of Europe / Novák / Large flock of Bramblings (Fringilla montifringilla) perched in tree with Mistletoe, Ldersdorf, Austria, February 2009

Fabio Liverani / A butterfly that has been parasitised by a fungus, Tambopata National Reserve, Amazonia, Peru

Nature Production / Butterfly {Niphanda fusca} larvae being raised by ants (Camponotus japonicus} in Aphid's nest, Japan

Konstantin Mikhailov / Red Mistletoe (Viscum sp) with berries, Ussuriland, SE Siberia, Russia

Tony Phelps / Roundworm infestation of captive African Rock python {Python natalensis} South Africa.

David Shale / Deep sea Anglerfish female with parasitic male attached to belly - stomach visible through mouth due to pressure change at surface where photographed. Male is x10 smaller than female and lives permane...

GRAHAM HATHERLEY / Parasitic broomrape {Cistanche phelypaea} among the desert plants it relies on, SE Morocco.