John Cancalosi / Sea Lamprey (Petromyzon marinus) close up of oral disc, from Cayuga Lake, New York, taken in an aquarium

John Cancalosi / Sea Lamprey (Petromyzon marinus) close up of oral disc, from Cayuga Lake, New York, taken in an aquarium

Franco Banfi / Blackstripe cardinalfish (Apogon nigrofasciatus) with parasite, Window, Boo Island, Raja Ampat, Irian Jaya, West Papua, Indonesia, Pacific Ocean

MYN / Joao P. Burini / Moth (Noctuidae) caterpillar with parasitic wasp eggs attached, Sao Paulo, Brazil. meetyourneighbours.net project

MYN / Joao P. Burini / Moth (Noctuidae) caterpillar with parasitic wasp eggs attached and Parasitic wasp (Braconidae), Sao Paulo, Brazil. meetyourneighbours.net project

Rod Williams / Tachinid Fly (Phryxe sp) Lewisham, London, September

Cyril Ruoso / Leaf infested by parasites, Barro Colorado Island, Panama

Cyril Ruoso / Red-billed Oxpecker (Buphagus arythrorhynchus) pair landing on Masai Giraffe (Giraffa tippelskirchi) to feed on parasites, Ngorongoro Conservation Area, Tanzania

Paul Harcourt Davies / Common rufous parasite fly (Tachina fera) on flowers in garden, Orvieto, Italy, May

Paul Harcourt Davies / Common rufous parasite fly (Tachina fera) on flowers in garden, Orvieto, Italy, May

Paul Harcourt Davies / Daddy longlegs spider (Pholcus phalangoides) infected with a fungal pathogen (possibly Gibellula pulchra) in a cave near Podere Montecucco, Orvieot, Umbria, Italy

Juergen Freund / Dead ant (Formicidae sp) infected by Ophiocordyceps fungus. Tanjung Puting National Park, Borneo, Central Kalimantan, Indonesia

Juergen Freund / Rafflesia flower (Rafflesia tuan-mudae) parasite on Tetrastigma vine. Sarawak, Borneo

Juergen Freund / Rafflesia flower (Rafflesia tuan-mudae) parasite on Tetrastigma vine. Sarawak, Borneo

Paul Harcourt Davies / Branched broomrape (Orobanche ramosa) in flower, near Plakias, Crete, April

Paul Harcourt Davies / Cytinus (Cytinus hypocistus) in flower, a species parasitic on the roots of various Cistus species. Akrotiri, Chania, Crete, April

Paul Harcourt Davies / Cytinus (Cytinus hypocistus) a species parasitic on the roots of various Cistus species. Akrotiri, Chania, Crete, April

Franco Banfi / Right whale (Eubalaena australis) breaching, with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Si...

Franco Banfi / Rare albino Southern Right whale (Eubalaena australis) breaching, with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natu...

Franco Banfi / Rare albino Southern Right whale (Eubalaena australis) breaching, with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natu...

Franco Banfi / Rare albino Southern Right whale (Eubalaena australis) breaching, with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Nat...

Franco Banfi / Rare albino Southern Right whale (Eubalaena australis) breaching, with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natu...

Franco Banfi / Southern right whale (Eubalaena australis) with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Site...

Franco Banfi / Southern right whale (Eubalaena australis) with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Site...

Franco Banfi / Detail of parasitic crustaceans named cyamids or whale lice (Cyamus ovalis) on the callosities of Southern right whale (Eubalaena australis) Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Herita...

Franco Banfi / Southern right whale (Eubalaena australis) with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Site...

Franco Banfi / Southern right whale (Eubalaena australis) with patches covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Site,...

Franco Banfi / Southern right whale (Eubalaena australis) with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Site...

Franco Banfi / Southern right whale (Eubalaena australis) with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Site...

Franco Banfi / Southern right whale (Eubalaena australis) with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Site...

Franco Banfi / Southern right whale (Eubalaena australis) with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Site...

Franco Banfi / Detail of parasitic crustaceans named cyamids or whale lice (Cyamus ovalis) on a Southern right whale (Eubalaena australis) Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Site, Chubut,...

Franco Banfi / Southern right whale (Eubalaena australis) with callus covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis) above eye. Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heri...

Franco Banfi / Southern right whale (Eubalaena australis) with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Site...

Franco Banfi / Southern right whale (Eubalaena australis) with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Site...

Franco Banfi / Southern right whale (Eubalaena australis) with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Site...

Franco Banfi / Southern right whale (Eubalaena australis) with calluses covered in parasitic crustaceans named cyamids or whale lice (Cyamus ovalis). Golfo Nuevo, Peninsula Valdes, UNESCO Natural World Heritage Site...

Will Watson / Horse Chestnut (Aesculus hippocastanum) leaves with Leaf minor (Cameraria ohridella) Herefordshire, UK November 2012

Nick Upton / Yellow dung fly (Scathophaga stercoraria) killed by pathogenic fungus of flies (Entomophthora muscae) clinging to a thistle leaf with wings spread, Wiltshire pastureland, UK, June.

Nick Upton / Parasite fly / Tachinid fly (Phasia hemiptera) a parasite of shieldbugs, feeding on ornamental flowers, Wiltshire garden, UK, August. . Property released.

Nick Upton / Parasite fly / Tachinid fly (Phasia hemiptera) a parasite of shieldbugs, feeding on ornamental flowers, Wiltshire garden, UK, August. . Property released.

Sue Daly / Female Cuckoo Wrasse (Labrus mixtus) with parasites (Anilocra frontalis). Guillaumesse, Sark, British Channel Islands, July.

Juan Manuel Borrero / Illustration of Pinworms / Threadworms (Enterobius vermicularis) and eggs. Pencil and watercolor painting.

Juan Manuel Borrero / Illustration of nematode (Rhabditis sp) anatomy. Pencil and watercolor painting.

Juan Manuel Borrero / Illustrations of pork tape worm (Taenia solium) with segmented body on the left, cross section of proglottid or body segment on the bottom middle and on the left illustrations of scolex or head. Penci...

Colin Varndell / Mistletoe (VIscum album) berries. Somerset, UK, November.

Adrian Davies / Common dodder (Cuscuta epithymum) parasitising Gorse (Ulex europaeus), Devon, England, July.

Adrian Davies / Common dodder (Cuscuta epithymum) parasitising Gorse (Ulex europaeus), Devon, England, July.

Andy Sands / Sand Wasp (Ammophila pubescens) carrying paralysed caterpillar of Common heath moth (Ematurga atomaria) back to burrow, Surrey, UK, August

Andy Sands / Sand Wasp (Ammophila pubescens) carrying paralysed caterpillar of Common heath moth (Ematurga atomaria) back to burrow, Surrey, UK, August

Andy Sands / Sand Wasp (Ammophila pubescens) stinging caterpillar of Beautiful Yellow Underwing moth (Anarta myrtilli), Surrey, UK, August

Andy Sands / Sand Wasp (Ammophila pubescens) carrying paralysed caterpillar of Beautiful Yellow Underwing moth (Anarta myrtilli) back to burrow, Surrey, UK, August

Andy Sands / Sand Wasp (Ammophila pubescens) carrying paralysed caterpillar of Beautiful Yellow Underwing moth (Anarta myrtilli) back to burrow, Surrey, UK, August

Anup Shah / African Buffalo (Syncerus caffer) male with Yellow-billed oxpecker (Buphagus africanus) removing parasites from it's face, Masai Mara National Reserve, Kenya. March

Juergen Freund / Spectacled flying fox (Pteropus conspicillatus) dead animal, casualty of paralytic tick bite, North Queensland, Australia

Juergen Freund / Spectacled flying fox (Pteropus conspicillatus) casualty of paralytic tick (Ixodes holocyclus) bite being cared for on site of colony by Jenny Mclean, North Queensland, Australia, November 2012

Juergen Freund / Spectacled flying fox (Pteropus conspicillatus) casualty of paralytic tick (Ixodes holocyclus) bite being cared for on site of colony by Jenny Mclean, North Queensland, Australia, November 2012

Juergen Freund / Spectacled flying fox (Pteropus conspicillatus) dead animal, casualty of paralytic tick bite, North Queensland, Australia

Chris Mattison / Flower of Hydnora (Hydnora africana) a rare plant parasitic on species of the genus Euphorbia. Cornellskop, Richtersveld, South Africa.

Alex Hyde / Dodder (Cuscuta sp) parasitising Rosebay Willowherb (Epilobium angustifolium) Gran Paradiso National Park, Aosta Valley, Pennine Alps, Italy. July.

SINCLAIR STAMMERS / Cattle biting louse (Damalinia bovis) on hairs, in temperate climates cattle may be infested with this species of Mallophaga. Length 3mm approximately

SINCLAIR STAMMERS / Cattle biting louse (Damalinia bovis) in temperate climates cattle may be infested with this species of Mallophaga. Length 3mm approximately

Mark Carwardine / Fin whale (Balaenoptera physalus) close-up showing stalked barnacles on dorsal fin, Sea of Cortez (Gulf of California), Baja California, Mexico, Endangered

Mark Carwardine / Close-up of barnacle on top of head of Grey whale (Eschrichtius robustus) San Ignacio Lagoon, Baja California, Mexico

Mark Carwardine / Grey whale (Eschrichtius robustus) close-up of barnacles and whale lice on skin of head, San Ignacio Lagoon, Baja California, Mexico

Mark Carwardine / Grey whale (Eschrichtius robustus) close-up of head showing barnacles and whale lice on skin, San Ignacio Lagoon, Baja California, Mexico

Mark Carwardine / Grey whale (Eschrichtius robustus) close-up of head showing barnacles and whale lice on skin, San Ignacio Lagoon, Baja California, Mexico

Mark Carwardine / Grey whale (Eschrichtius robustus) close-up of head showing barnacles and whale lice on skin, San Ignacio Lagoon, Baja California, Mexico

Mark Carwardine / Grey whale (Eschrichtius robustus) close-up of head showing barnacles and whale lice on skin, San Ignacio Lagoon, Baja California, Mexico

Mark Carwardine / Grey whale (Eschrichtius robustus) close-up of head showing barnacles and whale lice on skin, San Ignacio Lagoon, Baja California, Mexico

Alex Mustard / Basking shark (Cetorhinus maximus) feeding at the surface on plankton. Note the sea lampreys beneath the tail (Petromyzon marinus) Cairns Of Coll, Isle of Coll, Inner Hebrides, Scotland, UK, North Eas...

Andy Sands / Ichneumen wasp (Ichneumen sp.) ovipositing into Bulrush head, probable host Bulrush Wainscot moth, East Sussex, England UK, August

Andy Sands / Cuckoo bee (Melecta albifrons) parasite of (Anthophora plumipes) on old wall where host species nests, Hertfordshire, England, UK, April

Yukihiro Fukuda / Close up of the mouth and nose of a Japanese giant salamander (Andrias japonicus) with two Leeches (Hirudinea) attached, Japan, March

Tui De Roy / Turquoise jay (Cyanolyca turcosa) raising parasitic Giant cowbird chick, Bellavista cloud forest private reserve, 1700m altitude, Tandayapa Valleyk, Andean cloud forest, Ecuador

Tui De Roy / Volcan Alcedo giant tortoise(Chelonoidis nigra vandenburghi) in muddy water, possibly for thermoregulation or to deter parasites, Isabela Island, Galapagos

Tui De Roy / Volcan Alcedo giant tortoises (Chelonoidis nigra vandenburghi) wallowing in muddy pool, possibly for thermoregulation or to deter parasites, and misty clouds over the mountain, Isabela Island, Galapag...

Tui De Roy / Volcan Alcedo giant tortoise (Chelonoidis nigra vandenburghi) group in muddy stream, possibly for thermoregulation or to deter parasites, with sulphur fumaroles from Alcedo Volcanos slopes, Isabela is...

Tui De Roy / Volcan Alcedo giant tortoise (Chelonoidis nigra vandenburghi) wallowing in rain pools on caldera floor, possibly for thermoregulation or to deter parasites, Alcedo Volcano, Isabela Island, Galapagos

Tui De Roy / Volcan Alcedo giant tortoise (Chelonoidis nigra vandenburghi) wallowing in muddy rain pools on caldera floor possibly for thermoregulation or to deter parasites, Isabela island, Galapagos

Tui De Roy / Volcan Alcedo giant tortoise (Chelonoidis nigra vandenburghi) group in muddy pool, possibly for thermoregulation or control of parasites, Isabela Island, Galapagos

Tui De Roy / Volcan Alcedo giant tortoise (Chelonoidis nigra vandenburghi) group in muddy water, possibly for thermoregulation or control of parasites, Isabela Island, Galapagos

Tui De Roy / Volcan Alcedo giant tortoises (Chelonoidis nigra vandenburghi) group wallowing in a muddy pool, possibly for thermoregulation or to deter parasites, with sulphur fumaroles from Alcedo Volcano, Isabel...

Tui De Roy / Volcan Alcedo giant tortoises (Chelonoidis nigra vandenburghi) wallowing in a muddy pool, possibly for thermoregulation or to deter parasites, with sulphur fumaroles, Alcedo Volcano, Isabela Island,...

Tui De Roy / Volcan Alcedo giant tortoises (Chelonoidis nigra vandenburghi) wallowing in muddy water, possibly for thermoregulation or to deter parasites, Alcedo Volcano, Isabela Island, Galapagos

Philippe Clement / Horse / Equine roundworms (Parascaris equorum) in horse dung, France

Philippe Clement / Horse / Equine roundworms (Parascaris equorum) in horse dung, France

Paul Williams / Common / Southern crested caracara (Caracara plancus) dust bathing to remove parasites, Pantanal, Pocone, Brazil

Tony Phelps / Broadleaf sugarbush (Protea eximia) infected with bacterial parasite (Phtoplasma sp) causing Witch's broom, a growth deformity. Swartberg Mountains, western Cape, South Africa.

MYN / Joao P. Burini / Parasitic wasp (Ophion sp) tropical rainforest, Piedade, Sao Paulo, Brazil, June, meetyourneighboursproject.net

Ben Lascelles / Mantled howler monkey (Alouatta palliata aequatorialis) male, Canopy Tower, Soberania National Park, Panama

Ben Lascelles / Mantled howler monkey (Alouatta palliata aequatorialis) male, Canopy Tower, Soberania National Park, Panama

Ben Lascelles / Mantled howler monkey (Alouatta palliata aequatorialis) male, Canopy Tower, Soberania National Park, Panama

Ben Lascelles / Mantled howler monkey (Alouatta palliata aequatorialis) male with extensive botfly (Oestridae) lessions, Canopy Tower, Soberania National Park, Panama

Ben Lascelles / Mantled howler monkey (Alouatta palliata aequatorialis) male with extensive botfly (Oestridae) lessions, Canopy Tower, Soberania National Park, Panama

Ben Lascelles / Mantled howler monkey (Alouatta palliata aequatorialis) male with extensive botfly (Oestridae) lessions, Canopy Tower, Soberania National Park, Panama