Emanuele Biggi / Bell spider (Argyroneta aquatica), Italy, February.

Emanuele Biggi / Bell spider (Argyroneta aquatica), Italy, February.

Emanuele Biggi / Bell spider (Argyroneta aquatica) with its air bubble underwater, Italy. October. Controlled conditions.

Emanuele Biggi / Bell spider (Argyroneta aquatica) resting in its air filled bell underwater, Italy. October. Controlled conditions.

Robert Thompson / Diving bell spider (Argrpneta aquatica) Montiaghs Moss NNR, County Antrim, Northern Ireland. May.

James Dunbar / European water spider (Argyroneta aquatica) spinning a web underwater. Captive, native to Northern and Central Europe and Northern Asia.

James Dunbar / Close-up of a European water spider (Argyroneta aquatica) spinning a web underwater. Captive, native to Northern and Central Europe and Northern Asia.

James Dunbar / European water spider (Argyroneta aquatica) hunting mosquito larva. Captive, native to Northern and Central Europe and Northern Asia.

James Dunbar / Wide-angle shot of a European water spider (Argyroneta aquatica) collecting air for its nest. Captive, native to Northern and Central Europe and Northern Asia.

James Dunbar / European water spider (Argyroneta aquatica) collecting air for its nest. Captive, native to Northern and Central Europe and Northern Asia. Captive, native to Northern and Central Europe and Northern A...

James Dunbar / European water spider (Argyroneta aquatica) collecting air for its nest. Captive, native to Northern and Central Europe and Northern Asia. Captive, native to Northern and Central Europe and Northern A...

James Dunbar / Close-up of a European water spider (Argyroneta aquatica) collecting air for its nest. Captive, native to Northern and Central

MYN / Niall Benvie / Diving bell spider (Argyroneta aquatica) underwater, Finland, June.

MYN / Niall Benvie / Diving bell spider (Argyroneta aquatica) underwater gathering air, Finland, June.

MYN / Emanuele Biggi / Air-bell spider (Argyroneta aquatica) adult male underwater, Vercelli, Italy, February. Meetyourneighbours.net project

MYN / Emanuele Biggi / Air-bell spider (Argyroneta aquatica) adult male underwater, Vercelli, Italy, February. Meetyourneighbours.net project

Jan Hamrsky / Water spider (Argyroneta aquatica) detail of air bubble around its abdomen, Europe, July, controlled conditions

Jan Hamrsky / Water spider (Argyroneta aquatica) refilling its air supply, Europe, July, controlled conditions

Jan Hamrsky / Water spider (Argyroneta aquatica) with air bubble, Europe, July, controlled conditions

Stephen Dalton / European water spider {Argyroneta aquatica} underwater, UK, Argyrometidae

Stephen Dalton / Water spider (Argyroneta aquatica) underwater, in air bubble bell chamber, Argyronetidae

Stephen Dalton / Water spider (Argyroneta aquatica) underwater, with air bubble bell chamber, Argyronetidae

Stephen Dalton / Water spider (Argyroneta aquatica) underwater, with Woodlouse prey {Ascellus sp} Argyronetidae

Stephen Dalton / Water spider (Argyroneta aquatica) underwater, with Woodlouse prey {Ascellus sp} Argyronetidae

Stephen Dalton / European water spider {Argyroneta aquatica} underwater with louse prey, UK, Argyronetidae

Stephen Dalton / European water spider {Argyroneta aquatica} underwater in air bubble bell, UK, Argyronetidae

Stephen Dalton / European water spider {Argyroneta aquatica} underwater in air bubble bell, UK, Argyronetidae

Stephen Dalton / European water spider {Argyroneta aquatica} underwater, close up showing large jaws, UK, Argyrometidae

Stephen Dalton / European water spider {Argyroneta aquatica} underwater with its diving bell bubble of air, UK, Argyrometidae

Stephen Dalton / European water spider {Argyroneta aquatica} underwater, UK, Argyrometidae

SINCLAIR STAMMERS / European water spider (Argyroneta aquatica) on web

Willem Kolvoort / European water spider (Argyroneta aquatica) underwater in air bubble in garden pond, Holland

Willem Kolvoort / European water spider underwater (Argyroneta aquatica) sand winning pit, Holland

SINCLAIR STAMMERS / Water spider (Argyroneta aquatica) showing air bubble. England, UK, Europe

Adrian Davies / European water spider (Argyroneta aquatica). Southern England, UK, Europe

Adrian Davies / European water spider underwater, Southern England

SINCLAIR STAMMERS / Water spider underwater with air bubble, UK

Chris Shields / Illustration of Water / Diving bell spider (Argyroneta aquatica), Argyronetidae.