Franco Banfi / Freshwater turtle (Trachemys scripta venusta) swimming amongst Water lilies leaves, Gran Cenote, near Tulum, Quintana Roo, Yucatan Peninsula, Mexico.

Claudio Contreras / Mesoamerican slider turtle / terrapin (Trachemys scripta venusta) in sinkhole, Cenote Carwash, near Tulum, Yucatan Peninsula, Mexico, January

Claudio Contreras / Mesoamerican slider turtle / terrapin (Trachemys scripta venusta) in sinkhole, Cenote Carwash, near Tulum, Yucatan Peninsula, Mexico, January

Tim Fitzharris / Yellow-bellied Slider (Trachemys scripta scripta) turtle, North America

Konrad Wothe / Red-eared Slider (Trachemys scripta elegans) turtle, pair in pond, City Park, Munich, Germany

Cyril Ruoso / Red-eared slider (Trachemys scripta elegans) and Grass snake (Natrix natrix) basking on log. Seine et Marne, Ile-de-France. May.

Franco Banfi / Freshwater turtle (Trachemys scripta venusta) swimming under Water lilies leaves, Gran Cenote, Tulum, Quintana Roo, Yucatan Peninsula, Mexico.

Franco Banfi / Freshwater turtle (Trachemys scripta venusta) swimming in Gran Cenote, near Tulum, Quintana Roo, Yucatan Peninsula, Mexico.

Franco Banfi / Freshwater turtle (Trachemys scripta venusta) swimming in Gran Cenote, near Tulum, Quintana Roo, Yucatan Peninsula, Mexico.

David Perpinan / Phallus/penile prolapse in a captive Yellow bellied slider (Trachemys scripta). Small repro only

David Perpinan / Radiography of a captive female red-eared slider (Trachemys scripta) showing eggs within the uterus. Captive animal. Small repro only

John Cancalosi / Red-eared slider (Trachemys scripta elegans) in blue-green algae (Woronichinia naegeliana). Microcystin produced is toxic to wildlife and humans. Maryland. October 2018.