Receptor for nematocin (PubMed:23112336, PubMed:23112335). The activity of this receptor is mediated by G proteins which activate a phosphatidylinositol-calcium second messenger system (PubMed:23112336, PubMed:23112335). The activity of this receptor may be modulated by ntr-2, leading to reduced intracellular cAMP production (PubMed:23112335). Plays a role in gustatory associative learning (PubMed:23112336). Also plays a role in male mating behavior (PubMed:23112335). Detected in the left ASE gustatory neuron, the chemosensory neuron pairs ASH and ADF, and the PQR tail neuron (PubMed:23112336). In males, detected in hook and tail sensory neurons involved in vulval sensing and hermaphrodite contact, and in spicule protractor muscles (PubMed:23112335). Viable and fertile (PubMed:23112336). Gustatory associative learning in response to salt cues is disrupted (PubMed:23112336). Males have reduced reproductive success, due to a range of aberrant mating behaviors (PubMed:23112335). Double knockouts with ntr-2 partially rescue the reproductive phenotypes (PubMed:23112335). Belongs to the G-protein coupled receptor 1 family. Vasopressin/oxytocin receptor subfamily.