This species is known from three localities on the Pacific versant of the Andes of Ecuador at an altitude of 2,200-3,000m asl. The type locality is 15km north of Pallatanga, in Chimborazo Province. The second and third localities are at Cashca Totoras and Las Guardias, respectively, in Bolivar Province.
Habitat and Ecology
It inhabits humid montane forest and sub-páramo. There is no specific information known about breeding habits, though it is likely to be similar to other Atelopus species, with breeding taking place in streams.
This is an extremely rare species and it has not been recorded since 1988, despite searches, particularly at Cashca Totoras (Bustamante 2002). This suggests that a serious decline has taken place.
The major threat is likely to be chytridiomycosis, leading to a catastrophic population decline, as has occurred in many other montane species of Atelopus. The disease has been confirmed in Gastrotheca pseustes in the same area. Other major threats include habitat loss due to agriculture, logging and infrastructure development for human settlement, and agricultural pollution.
The range of the species does not encompass any protected areas. However, it was protected in Bosque Protector Cashca Totoras (in Bolívar Province), where it disappeared. The species might be extinct, and it might be too late for measures such as captive breeding; additional survey work is required to confirm the continued persistence of this species in the wild.
Santiago Ron, Luis A. Coloma, Martín R. Bustamante, Diego Cisneros-Heredia, Mario Yánez-Muñoz 2004. Atelopus arthuri. In: IUCN 2014