Martin Gabriel / Firefly crocus (Crocus sieberi) flowers in snow, Bavaria, Germany, March.

Paul Harcourt Davies / Spring Crocus (Crocus vernus) in flower in snow, Campo Imperatore, Gran Sasso, Appennines, Abruzzo, Italy, May

Kerstin Hinze / Crocus (Crocus napolitanus) flowering in spring garden at Schlosspark Husum, Schleswig-Holstein, Germany

Kerstin Hinze / Crocus (Crocus napolitanus) flower, Schlosspark Husum, Schleswig-Holstein, Germany

Phil Savoie / Early bumblebee (Bombus partorum) queen feeding from crocus flower Monmouthshire, Wales, UK. March.

Heather Angel / Solitary bee (Apoidea) feeding on Crocus (Crocus korolkowii), covered in pollen. Ansob Pass, Tajikistan. April.

Heather Angel / Crocus (Crocus sp) flower from above, closing in evening. Focus stacked.

Heather Angel / Celandine crocus (Crocus korolkowii) carpets in areas of snowmelt. Near Ansob Pass, Tajikistan. April 2014.

Heather Angel / Honey bee (Apis mellifera) covered in pollen emerging from nectaring in Crocus (Crocus sp). On nature reserve, Surrey, England, UK. March.

Heather Angel / Celandine crocus (Crocus korolkowii) carpet in area of snowmelt. Pollinated by solitary bees and bumblebees. In valley, near Ansob Pass, Tajikistan. April 2014.

Konrad Wothe / Crocus (Crocus vernus) flowering in Upper Bavaria with Karwendel mountains in distance, Germany, April.

Guy Edwardes / Dew covered Crocus (Crocus sativus), Bamburgh, Northumberland, UK, February.