New species of deep-sea squat lobsters (Decapoda: Anomura: Galatheoidea) from Guadeloupe, French West Indies, unveiled through integrative taxonomy

Abstract

During two deep-sea expeditions off the island of Guadeloupe, French West Indies, several specimens belonging to MunidaLeach, 1820 and MunidopsisWhiteaves, 1874 (Galatheoidea) were collected. Further study, integrating morphological and molecular data, indicated that some of the specimens belonged to three undescribed species, one to Munida and two to Munidopsis. Munida anteaen. sp. is morphologically closely related to the Atlantic species M. microphthalma A. Milne-Edwards, 1880. Both species can be easily distinguished morphologically and represent independent evolutionary lineages. The closest relative to Munidopsis balconin. sp. is M. glabraPequegnat & Williams, 1995 from the Gulf of Mexico. They can be distinguished by the armature of the carapace and pereiopods, among other differences. Munidopsis pholidotan. sp. is sister to M. squamosa (A. Milne-Edwards, 1880) and both are considered cryptic species, distinguished only by molecular characters and subtle morphological differences like the number of epipodites. Our phylogenetic results show some monophyletic groups within Munidopsis and Munida, and the existence of morphological convergences.

Cosmopolitan abyssal lineages? A systematic study of East Pacific deep-sea squat lobsters (Decapoda: Galatheoidea: Munidopsidae)

“…Phylogenetic analyses were performed using two different data sets: (1) concatenated data of 152 taxa and (2) COI P. C. Rodríguez-Flores et al Invertebrate Systematics data alone that included a larger number of terminals available in public databases, with 212 sequences of 82 named species. We first retrieved sequences from previous publications from the NCBI database (Ahyong et al 2011;Bracken-Grissom et al 2013;Rodríguez-Flores et al 2018, 2019a, 2022a, 2022bDong et al 2019. In the first dataset (1), we included wide taxonomic sampling across Galatheoidea (Galatheidae, Munididae, Munidopsidae and Porcellanidae), providing a phylogenetic framework to test the systematic position of the East Pacific species.…”

“…Munidopsids currently comprise nearly 300 species in 4 genera: Galacantha A. Milne-Edwards, 1880, Leiogalathea Baba, 1969, Munidopsis Whiteaves, 1874and Shinkaia Baba & A.B. Williams, 1998Rodríguez-Flores et al 2022a). Within this family, the global genus Munidopsis is the most speciose, with 270 species described to date.…”

“…Additional species are added nearly every year (e.g. Rodríguez-Flores et al 2018, 2022aDong et al 2019Marin 2020), suggesting that a great deal of diversity remains to be discovered. Munidopsids occur in deep-sea benthos across a latitudinal gradient in both hemispheres (Baba 2005) but few records are attributed to Antarctic waters (García Raso et al 2008).…”

“…Sampling these squat lobsters, as for other deep-sea fauna, is costly both in terms of time and funding. Moreover, several Munidopsis species are rare, known from only a few localities, few individuals or even only from the holotype (Rodríguez-Flores et al 2022a). These factors have contributed to incomplete knowledge of species diversity and distribution patterns, making the assessment of intraspecific variation and consequent establishment of the basis for species delimitation within Munidopsis difficult.…”

Munidopsis geyeri and M. exuta (Crustacea: Munidopsidae): A study of two deep-sea, amphi-Atlantic species that co-occur in the southern Gulf of Mexico

“…Alcock 1901;Benedict 1902;Faxon 1893;Henderson 1885) led to the unification of all the species under the genus Munidopsis on the grounds that most of the species shared morphology justifying placement under a single genus, but also because the previously applied genera were based upon character states that were apparently transitional in many species, thereby making their generic limits questionable (Chace 1940). At present, the genus Munidopsis encompasses 272 species (Rodríguez-Flores et al 2022;WoRMS 2022). Exploration in deep-sea habitats and technological developments for small scale sampling have facilitated collections of new species, while the application of molecular phylogenetics has facilitated the recognition of cryptic species (e.g.…”