Hot-springs
Guides
Cicindelidia haemorrhagica haemorrhagica
Wetsalts Tiger Beetle
Cicindelidia haemorrhagica haemorrhagica is a subspecies of tiger beetle known for its remarkable tolerance of extreme thermal environments. Populations in Yellowstone National Park inhabit hot springs with water temperatures exceeding 70°C (158°F) and pH ranging from highly acidic (2.7) to strongly alkaline (~9), making them among the most thermally tolerant insects known. The subspecies exhibits unique physiological and behavioral adaptations that allow it to function as an apex predator in these extreme habitats, including heat-reflective ventral plates and an apparent lack of cooling behaviors despite high ambient temperatures.
Ephydra
brine flies, alkali flies
Ephydra is a genus of shore flies (Ephydridae) with cosmopolitan distribution. Several species are notable for inhabiting extreme environments, including hypersaline lakes and hot springs. The genus includes the alkali fly (Ephydra hians), which forms dense populations in alkaline lakes such as Mono Lake, California, and serves as a critical food source for migratory birds. Larvae are aquatic or semi-aquatic, with morphological adaptations for feeding and respiration in mineral-rich waters.