Description of Brachistosternus pehuenche sp. nov. (Scorpiones, Bothriuridae), a new scorpion species from the upper Maule Valley, in the southern Chilean Andes

Brachistosternus pehuenche sp. nov. (Scorpiones, Bothriuridae) is described from the Mauline Andean forests of the northern Chilean Patagonia, located within the upper basin of the Maule Valley. Its unique geography and the discovery of this partial isolation, as a result of the surrounding higher altitudes, support the role of this valley as a biodiversity hotspot, fostering a variety of endemic epigean arthropods.

The discovery of this third endemic scorpion species highlights the area’s ecological uniqueness. The species is most similar to Brachistosternus negrei, a species found in the southern Chilean forests, but distinct morphological traits, such as pigmentation patterns and metasomal structures, clearly separate the two. This study underscores the ecological value of the Maule Valley, which, despite its high endemism, remains unprotected and is subject to significant anthropogenic pressures, including agriculture, hydropower projects, and international transit routes.

The need for conservation initiatives in this region is critical to preserve its exceptional biodiversity. This work not only adds to the taxonomy of Brachistosternus but also raises fundamental questions about the processes driving endemism in the Andes and the broader implications for the conservation of montane ecosystems.