Hans Christoph Kappel / Trapdoor spider opening 'door' to emerge from its den, Spain

Hans Christoph Kappel / Trapdoor spider emerging from its den; note 'door' pushed to one side, Spain.

Chris Mattison / Buzzing spider (Anyphaena accetuata) on white background. Wye Valley , Monmouthshire, Wales, UK. February.

Chris Mattison / Buzzing spider (Anyphaena accentuata) on white background. Wye Valley, Monmouthshire, Wales, UK. February.

Konrad Wothe / Trapdoor spider (Ctenizidae) at trapdoor entrance, Panguana Reserve, Huanuco Province, Peru.

Konrad Wothe / Trapdoor spider (Ctenizidae) at trapdoor entrance, retreats into burrow, Panguana Reserve, Huanuco Province, Peru.

Konrad Wothe / Trapdoor spider (Ctenizidae) at trapdoor entrance, retreats into burrow, Panguana Reserve, Huanuco Province, Peru.

Andy Sands / Purse web spider (Atypus affinis) top of purse web above ground, Surrey, England, UK, July

Andy Sands / Purse web spider (Atypus affinis) adult removed from tunnel, Surrey, England, UK, July

Andy Sands / Purse web spider (Atypus affinis) adult removed from tunnel, Surrey, England, UK, July

MYN / Dimitris Poursanidis / Trapdoor spider (Cyrtocarenum cunicularium) Crete, Greece, October. meetyourneighbours.net project

MYN / Dimitris Poursanidis / Trapdoor spider (Cyrtocarenum cunicularium) Crete, Greece, October. meetyourneighbours.net project

MYN / Dimitris Poursanidis / Trapdoor spider (Cyrtocarenum cunicularium) Crete, Greece, October. meetyourneighbours.net project

MYN / Dimitris Poursanidis / Trapdoor spider (Cyrtocarenum cunicularium) Crete, Greece, October. meetyourneighbours.net project

Luiz Claudio Marigo / Trapdoor spider (Actinopus sp) at theentrance of its den, Tableland Atlantic rainforest of Vale Natural Reserve, municipality of Linhares, Espírito Santo State, Eastern Brazil.

Luiz Claudio Marigo / Trapdoor spider (Actinopus sp) at the entrance to its den, Tableland Atlantic rainforest of Vale Natural Reserve, municipality of Linhares, Esparito Santo State, Eastern Brazil.

MYN / Clay Bolt / Southern trapdoor spider (Ummidia audouini) South Carolina, USA, June. meetyourneighbours.net project

MYN / Clay Bolt / Southern trapdoor spider (Ummidia audouini) South Carolina, USA, June. meetyourneighbours.net project

MYN / Clay Bolt / Southern trapdoor spider (Ummidia audouini) in defensive posture, South Carolina, USA, June. meetyourneighbours.net project

Barry Mansell / Trap-door spider (Ummidia audouini) female on flower, South Carolina, USA, April

Piotr Naskrecki / Trapdoor Spider (Ummidia sp) family Ctenizidae, Guyana

Hans Christoph Kappel / Camouflaged trapdoor spider trap closed Ctenizidae) Spain

Hans Christoph Kappel / Camouflaged trapdoor spider trap open (Ctenizidae) Spain

Hans Christoph Kappel / Trapdoor spider (Ctenizidae) Spain

Hans Christoph Kappel / Trapdoor spider emerging from tunnel (Ctenizidae) Spain

Simon Williams / Trapdoor of Trapdoor spider {Liphistius malayanus} Fraser's Hill, Malaysia

Simon Williams / Trapdoor of Trapdoor spider {Liphistius malayanus} Fraser's Hill, Malaysia

Hans Christoph Kappel / Camouflaged trapdoor spider trap (Ctenizidae) Spain

David Shale / Trapdoor spider emerging from burrow {Ctenizidae} Tsavo NP, Kenya

Hans Christoph Kappel / Trapdoor spider emerging from its den, Sardinia

Hans Christoph Kappel / Trapdoor spider. Sardinia, Italy

Barry Mansell / Trapdoor Spider (Ummidia audouini) defensive posture on leaf, captive

Barry Mansell / Torreya trapdoor spider {Cyclocosmia torreya} emerging from trapdoor, Florida, USA

Joel Sartore / Photo Ark / Torreya trap-door spider (Cyclocosmia torreya) female, portrait, Verve Biotech, Nebraska. Captive, occurs in Florida, USA.

Joel Sartore / Photo Ark / Torreya trap-door spider (Cyclocosmia torreya) female, portrait, Verve Biotech, Nebraska. Captive, occurs in Florida, USA.

Joel Sartore / Photo Ark / Torreya trap-door spider (Cyclocosmia torreya) female, portrait, Verve Biotech, Nebraska. Captive, occurs in Florida, USA.

Roman Willi / Purseweb spider (Atypus sp.) resting in leaf litter, Lucerne, Switzerland. June. Focus stacked image.

Michel Poinsignon / The tube-like web of the Purse-web spider (Atypus affinis) on grass, Lorraine, France. May.