[2] The lizard is found in the Marlborough Sounds / Cook Strait area of New Zealand.

[1][3] This species was described by University of Otago researchers led by Lachie Scarsbrook in 2023.

The Brothers Islands (Māori: Ngāwhatu Kai Ponu), where the largest extant population exists, falls under the regional tribal authority of Te Ātiawa.

[5] Currently the largest and most stable population of Tohu gecko is located on North Brother Island.

[5] A population of 40 of these geckos, thought at the time to be H. duvaucelii, were translocated in 1998 to Mana Island, where they have successfully established and bred.