Mangrove horseshoe crab (Carcinoscorpius rotundicaudaLatreille, 1802) populations reveal genetic break in Strait of Malacca, with connectivity along southern coasts of Peninsular Malaysia

Abstract

1. The mangrove horseshoe crab, Carcinoscorpius rotundicauda, has divergent populations between the east and west coasts of Peninsular Malaysia, with the southern coast acting as a land barrier. The actual position of such a genetic break along Peninsular Malaysia as well as the connectivity status of the southernmost C. rotundicauda populations with east and west coast populations remain unexplored, however. 2. The aim was to investigate the genetic diversity and structure of C. rotundicauda populations from the west (Kuala Sepetang in State Perak), east (Balok in State Pahang), and southern (Pendas in State Johor) coasts of Peninsular Malaysia. Haemolymph samples from adult C. rotundicauda specimens (n = 152) and eggs from their freshly deposited nests (n = 190) were collected monthly (from January 2016 to January 2017) for the sequencing of mitochondrial cytochrome c oxidase subunit I (COI). 3. Gene isolates of C. rotundicauda from the present study were compared with National Center for Biotechnology Information (NCBI) GenBank sequences to cover most of the range of the species in Asia. A neighbour-joining tree strongly supported two clades, separating the west-coast populations from the south-and east-coast populations, with further substructure patterns. 4. Both haplotype network and barrier analyses revealed a genetic break within the Strait of Malacca instead of the southern tip of Peninsular Malaysia. The southernmost samples from the Strait of Johor formed a haplotypic diverse gene pool that appeared only as a subclade of the eastern populations. In a detailed Nur Fairuz-Fozi and Ludwig Triest are co-first authors. Behara Satyanarayana and Farid Dahdouh-Guebas are co-last authors.

Distinguishing Original and Non-Original Stands at the Zhanjiang Mangrove National Nature Reserve (P.R. China): Remote Sensing and GIS for Conservation and Ecological Research

“…In addition to the natural and anthropogenic impacts on mangrove covers, inbreeding might reduce reproductive potentials (along with loss of genetic diversity) and its resilience towards environmental change [32,33]. Since long-term survival of a species depends on its genetic conservation, molecular marker methods have been used to evaluate genetic characteristics, such as structure, flows, barriers, past sea-level changes [34][35][36][37]. However, these gene-tests are still limited due to lack of reliable historical data (e.g., forest age) from many mangrove locations.…”