**Abstract**

At first glance, the ground surrounding the glacier front and the streams originated by melting glaciers seem to be too extreme to host life forms. They are instead ecosystems, colonized by bacteria, fungi, algae, mosses, plants and animals (called the "glacial biodiversity"). The best adapted animals to colonize glacier surface, the recently deglaciated terrains and glacial streams are insects, specifically the ground beetles (carabids) and the non-biting midges (chironomids). This chapter aims to overview the species colonizing these habitats, their adaptation strategies to face natural cold and anthropogenic heat and the extinction threats of glacial retreat and pollution by emerging contaminants. Notes on their role in the glacial-ecosystem functioning and related ecosystem services are also given.

**Keywords:** carabid beetles, chironomids, cold-adapted species, debris-covered glaciers, extinction risk, glacier forelands, rock glaciers
