G-protein coupled receptor (GPCR) that forms a heterodimer with daf-37 to control dauer formation and behavior. Required for the response to dauer inducing pheromones such as the ascarosides ascr#2, ascr#3 and ascr#5. Heterodimer; with daf-37. Expressed in the ASI and ASK chemosensory neurons and in the IL-2 interneurons, but weakly expressed in other head neurons in hermaphrodites. Belongs to the G-protein coupled receptor 1 family.