In this study, four new species of land hermit crabs (Crustacea: Decapoda: Anomura: Coenobitidae: Coenobita Latreille, 1829) are described from Indonesia. These descriptions are based on evidence from morphological differences as well as mitochondrial 16S rDNA and cytochrome c oxidase subunit I data. Among the new species, Coenobita moluccensis n. sp. (from Aru Island, Maluku), C. patsyae n. sp. (from Central Sulawesi and Southeast Sulawesi), and C. celebensis n. sp. (from Central Sulawesi) form a major clade on the phylogenetic tree, exhibiting similarities in morphology, particularly in the male sexual tubes—a character they share with their closely related counterpart, C. lila Rahayu, Shih & Ng, 2016. Although the four species are similar in overall morphology, they can be distinguished by differences in the left third pereopod, the second article of the antennal peduncles, granulation on the pereopods, as well as their live coloration. Coenobita granularis n. sp., found in Central Sulawesi, shares morphological similarities with the genetically closely related C. pseudorugosus Nakasone, 1988, particularly in the male sexual tubes. However, the two species can be distinguished by differences in the morphology of the male sexual tubes, the presence of tubercles on the left cheliped, the left third pereopod, as well as their live coloration. Additionally, a newly recorded species, C. variabilis McCulloch, 1909, has been confirmed in West Papua. This study brings the total number of Coenobita species known from Indonesia to 13.
Coenobita moluccensis, C. patsyae, C. celebensis, C. variabilis, New species, Newly recorded species, Morphology, 16S rDNA, Cytochrome c oxidase subunit I (COI), Phylogeny
