G-protein coupled receptors (GPCR) constitute the largest family of transducing cell surface proteins, and are integral to cell communication via an array of ligands, including neuropeptides. The crustacean hyperglycaemic hormone (CHH) neuropeptide family includes crustacean hyperglycaemic hormone (CHH), moult-inhibiting hormone (MIH), GIH/VIH (gonad/vitellogenesis-inhibiting hormone), and MOIH (mandibular organ-inhibiting hormone). MIH is a key neuropeptide which controls growth and reproduction in crustaceans. It inhibits ecdysteroid biosynthesis via cyclic nucleotide second messengers by binding to a yet uncharacterized GPCR. When MIH release stops, ecdysteroids are synthesized by the Y-organs (YO) and released to the hemolymph. A peak in ecdysteroid titer is followed by a molting event. Ninety-two GPCR sequences from blackback land crab (Gecarcinus lateralis), a well-studied species in the context of molt regulatory pathways, were obtained by scanning a YO transcriptome against the Pfam database. Phylogenetic analysis classified 57 contigs in class A (Rhodopsin-like receptor), 28 in class B (Secretin receptor), and 7 in class C (metabotropic glutamate). Further phylogenetic analysis of class A GPCRs identified neuropeptide receptors for allatostatin A, allatostatin B, bursicon, CCHamide, FMRFamide, proctolin, corazonin, relaxin, and the biogenic amine serotonin. Three class A GPCRs clustered with putative receptors for CHH family neuropeptides (CHHRs). Tissue expression of these predicted CHHRs from different organs of G. lateralis was examined and will be followed by functional receptor assays to validate the phylogenetic and structural analyses. Supported by U.S. National Science Foundation (IOS-1257732).