Hermit crabs were collected over 13 years from different habitats in the coastal lagoons of Términos, Alvarado, Tamiahua, and Madre in the southwestern Gulf of Mexico. The distribution, habitat, relative abundance, shield-length data, and zoogeographical affinities of each of the ten species are presented. A zoogeographical analysis assigned the species to four distribution patterns: Eurytopic (Clibanarius vittatus, Petrochirus diogenes, Paguristes tortugae, Pagurus criniticornis); Endemic to the Gulf of Mexico (Paguristes hernancortezi); Warm-Temperate Caribbean (P. hummi, Pagurus maclaughlinae); and Warm-Temperate (P. annulipes, P. longicarpus, P. pollicaris). Five species extend their previously recorded distribution southward, and eight species are now recorded further south within the Gulf of Mexico.