FMRFamides and FMRFamide-like peptides are neuropeptides. KPSFVRF-amide: Has no effect on somatic body wall muscle, inhibits contraction of vaginal vera muscle, and inhibits the activity of the dissected pharyngeal myogenic muscle system (PubMed:9920762, PubMed:16187307). Acts as a ligand for the npr-22 receptor in vitro (PubMed:16377032). Each flp gene is expressed in a distinct set of neurons. Expressed in eggs and larvae, but not in adults. Belongs to the FARP (FMRFamide related peptide) family.