The global distribution and richness of frog crabs (Raninoidea)

The study of species distributions is fundamental for environmental research, conservation planning, and resource management. However, it is not always possible to obtain access to these data, making it difficult to reach the goal of quantifying biodiversity. The distribution of many crustacean groups is poorly studied; such is the case of the superfamily Raninoidea (frog crabs). In order to reduce this information gap, herein we mapped and described the world distribution of members of this superfamily by performing a data visualization analysis. We carried out an extensive review of species records and distribution data from different databases, collections, and unpublished data. Furthermore, we conducted a species richness analysis and an agglomerative cluster analysis to identify biogeographic regions. Both analyses were carried out using the software Biodiverse (v. 2.0). Results showed that Raninoidea is composed of 46 species across a pantropical distribution. For this study, the globe was divided into 30 pre-established biogeographical regions, ranging from the Indo-Pacific seas & Indian Ocean (IPSIO) region, represented by 19 species and a maximum richness of eight species, to the Southern Ocean (SO) region, represented by only one species. Some species are distributed across regions while some are found exclusively in a single region. Due to issues with accuracy and sufficiency of raw data, we also calculated the Chao 1 and ACE indices, which suggest that other species have yet to be recorded.