Taxonomic and conservation status of Majoidea “Spider Crabs” from Indonesia: Recommendations for management

Abstract

The Majoidea contains either six, seven, or eight valid families according to different sources. This has resulted in difficulties with the taxonomy and conservation of this superfamily. The Majoidea in Indonesia waters were documented in the past, however, their taxonomy and conservation status were booth poorly documented. The aims of this study were (1) to determine the taxonomic status of; and (2) to evaluate the conservation status of Indonesian majoid crabs. The IUCN red list was used to evaluate the conservation status of Majoidea identified based on DNA barcodes Mitochondrial cytochrome c oxidase I gene (COI). Considering genetic distances between specimens, genetic divergence, the phylogenetic trees and concepts of genetic species, the superfamily Majoidea is composed of multiple species or genera that belong to different subfamilies. This study differentiated all individual sequences as different species or genera except three sequences from Aceh and Solor. The results were classified into two groups based on taxonomic status. The first group comprised species, e.g. Schizophrys aspera, Tylocarcinus styx, Perinia tumida, Menaethius orientalis, and Pisa armata/Hyastenus elongatus. The second group comprise such as Majidae sp., Brachyura sp. and Decapoda sp. The Majoidea was recognized and differentiated based on data set comprising 45 haplotypes, 227 segregating sites, 0.99 haplotype diversity, and 0.17 nucleotide diversity. Minimum Spanning Tree analyses of COI gene sequences reveal 47 distinct groups of operational taxonomic units corresponding to genera or species. In 2021, all of Majoidea taxa were listed as either data deficient or not evaluated in the IUCN Red List or appendices, due to insufficient data. These results suggest that comprehensive follow-up surveys of the taxonomic and conservation status of Majoidea are still urgently required.