From Packer, L. 2005. Species Profile: Halictus pinguismentus. In Shepherd, M. D., D. M. Vaughan, and S. H. Black (Eds). Red List of Pollinator Insects of North America. CD-ROM Version 1 (May 2005). Portland, OR: The Xerces Society for Invertebrate Conservation: Not known, but, based on closely related species and allometry the four known specimens, likely eusocial with potential queens overwintering before producing one or more worker brood(s) in the spring and summer before then producing males and the next generation of overwintering queens. This species lives in Guadeloupe Island in the Pacific Ocean, off the coast of Baja California
