Mud adders found for first time in South Australia in 2022 on River Murray flood plains near Renmark

One of the venomous mud adders – the De Vis banded snake – found at Chowilla Game Reserve near Renmark in 2022.
Image by Connor Margetts, courtesy ABC News, Adelaide
Venomous mud adders were found for the first time on South Australian River Murray floodplains at Chowilla Game Reserve near Renmark in 2022.
The adders – known as the De Vis banded snake – were discovered by a group including reptile keeper Scott Regan and University of South Australia philosophy doctorate herpetology student Shawn Scott. They were searching for endangered southern bell frogs when they discovered four of the reptiles, the first of them concealed in a crack in dried mud, biting onto a southern bell frog.
Three other yellowy orange brown mud adders (Denisonia devisi) that grew up to 60 centimetres long were found nearby; one at the base of a large river redgum, and others also in soil cracks. The snake is widespread in Queensland and northern New South Wales but endangered in Victoria, and the sighting of the first adder at Chowilla Game Reserve also was believed to be the first where the species had been seen consuming the southern bell frog.
Regan said the mud adders had wide range and it was possible the ones his group spotted had travelled from a “tiny distribution found in Victoria that is considered endangered”, that was about 50 kilometres west from where they were camping. The snakes were considered mildly venomous, meaning a bite would generally create itchiness or redness “but everyone reacts to venom very differently”
. The adders' discovery by Regan and Scott, also with Harrison Jones, Connor Margetts and Sean Kirby, was published in an article in Herpetological Conservation and Biology. The authors believe their discovery underlined the need for greater conservation efforts in Australia’s river systems, particularly for reptiles, as many snake species were small and lived in isolated or specialised ecosystems: “If we are to mitigate biodiversity loss among our reptiles, we need to monitor not only remote or poorly understood ecosystems, but also areas that have extensive survey histories, which could result in the discovery of species that may have been undetected in the past”.
The adders discobery brings South Australia’s venomous snake species to 37. The snake’s scientific and common names refer to Charles Walter de Vis (1829-1915), first director of the Queensland Museum and renowned herpetologist.