Chirostyloid and galatheoid squat lobsters (Decapoda: Anomura) from Andaman and Nicobar Islands, India, with three new species

The squat lobster fauna of the Andaman and Nicobar waters, India is known to be represented by more than 40 species from 19 genera and six families. Seven species, including three new to science, collected from six dedicated surveys of the Fishery Oceanographic Research Vessel Sagar Sampada during 2011-2019 are described. Gastroptychus valdiviae Balss, 1913 is redescribed based on the syntype and the newly collected material. Grimothea krishaha sp. nov. and an unidentified species provisionally assigned to Grimothea Leach, 1820 are reported. These two species of Grimothea differ from known congeners in the spination on the carapace, pleon, antennule, antenna and third maxilliped. Examination of the syntype and newly collected specimen revealed that Munida vigiliarum Alcock, 1901 should be transferred to Leptonida Macpherson and Baba in Machordom et al., 2022. Leptonida vigiliarum comb. nov. is here redescribed. Trapezionida aequispina sp. nov. differs from related species in the spination on the carapace, and in the shape and relative lengths of the second to fourth pereopod dactyli. Trapezionida bharuchai sp. nov. differs from related species in the carapace morphology, the presence of a mesial spine on the antennal peduncle second article, and the armature on pereopods. Leiogalathea sp. does not resemble known congeners in morphological aspects, but because of the poor condition of the unique specimen presently available for study, formal description is deferred in the hope that additional material will be collected. With this report, the number of species reported from the region increases to 47.