Neil Aldridge / Two Lady's slipper orchids (Cypripedium calceolus) in flower in spring in woodland near Kuressaare, Saaremaa, Estonia.

Radomir Jakubowski / Ladys slipper orchid (Cypripedium calceolus), Bavaria, Germany, May. 2nd Prize in the Melvita Nature Images Awards competition 2014.

Dong Lei / Ellen's paphiopedilum orchid (Paphiopedilum helenae). Nonggang Natural Reserve, Guanxi Province, China.

Dong Lei / Ellen's paphiopedilum orchid (Paphiopedilum helenae) on rock. Nonggang Natural Reserve, Guanxi Province, China.

Dong Lei / Ellen's paphiopedilum orchid (Paphiopedilum helenae) on rock. Nonggang Natural Reserve, Guanxi Province, China.

Dong Lei / Ladies slipper orchid (Cypripedium elegans) Mt Qomolangma National Park, Qinghai Tibet Plateau, China.

Heather Angel / Slipper orchid (Cypripedium tibeticum), two flowers. Balangshan, Wolong, Sichuan Province, China. June.

Andy Sands / Lady's Slipper Orchid (Cypripedium calceolus) British specimen kept as part of collection at Kew Gardens, London, England, UK, May - Focus Stacked

Andy Sands / Lady's Slipper Orchid (Cypripedium calceolus) British specimen kept as part of collection at Kew Gardens, London, England, UK, May - Focus Stacked

Paul Williams / Kinabalu orchid (Paphiopedilum lowii) Mount Kinabalu. Borneo.

Paul Williams / Kinabalu orchid (Paphiopedilum lowii) Mount Kinabalu. Borneo.

Werner Bollmann / Lady's slipper orchid (Cypripedium calceolus) Bjorkskogsnas, Sweden, June.