Revisiting the phylogeny of Callianassidae (Crustacea: Decapoda: Axiidea) with descriptions of a new genus and four new species from the Indo-West Pacific

Abstract Ghost shrimps of the family Callianassidae Dana, 1852 are a group of obligate burrowers frequently encountered in soft sediments of the shelf or reef lagoons. Recent multi-gene molecular phylogenetic studies resulted in a reclassiffcation of Callianassidae, now containing 27 genera and ∼130 extant species. However, some intergeneric relationships within this family were still unsatisfactorily resolved, and the monophyly of several genera were unexplored in prior studies. In this study, we reconstruct the phylogeny of Callianassidae, based on two matrices (4-gene and 21-gene), with addition of more species. The 4-gene tree presents a similar topology to that reported by Robles et al. (2020), yet with low support and unsettled phylogenetic positions of Biffarius and Pugnatrypaea. Analyses of the 21-gene matrix derived from genome-skimming sequencing data recover a robust phylogeny of Callianassidae strongly supporting the composition of four major clades, all the intergeneric relationships, and monophyly of each polytypic genus included. In addition, with support from molecular evidence, a new genus and species, Papuallianassa duris gen. et sp. nov., two new species of Jocullianassa, J. comica sp. nov., J. jester sp. nov., and one new species of Scallasis, S. tomokomaii sp. nov., are described based on collections from the Indo-West Pacific.