The Malay Peninsula as a barrier to gene flow in an Asian horseshoe crab species, Carcinoscorpius rotundicauda Latreille

Abstract

a b s t r a c tHorseshoe crabs are marine arthropods that are amongst the oldest living creatures that still exist today. Among the four extant species of horseshoe crabs, Carcinoscorpius rotundicauda differs from the other species by having poisonous eggs and lays its eggs in sandy-mud areas near river mouths. With the rapid development of coastal areas worldwide, C. rotundicauda habitats are decreasing. Until now, however, there has not been any study on the species' genetic variation. Simple sequence repeat (SSR) and intersimple sequence repeat (ISSR) markers were employed to study the genetic variation in five C. rotundicauda populations from the east and west coasts of the Malay Peninsula. Both markers showed differing levels of genetic variation, but concurred on the pattern of genetic structuring among populations of the species. This includes showing that little, although significant, genetic differentiation is present among populations, suggesting a low rate of gene flow among populations. The results also suggested that C. rotundicauda may be subjected to the land barrier effect of the Malay Peninsula, whereby gene flow is limited between populations occurring on both sides of the peninsula, increasing their genetic differentiation through time.

Mitochondrial DNA sequence of the horseshoe crabTachypleus gigas

“…Genetic differences have been found in the same HSC species, including T. gigas , belonging to different geographical locations, which could be explained by multiple factors such as the limited migratory capacity of HSCs that influence the gene flow between populations, among others (Xia 2000 ; Ismail and Sarijan 2011 ; Rozihan and Ismail 2011 ; Obst et al 2012 ; Adibah et al 2015 ; Liew et al 2015 ; Periasamy et al 2017 ).…”

Genetic structures across a biogeographical barrier reflect dispersal potential of four Southeast Asian mangrove plant species

“…Post-glacial sea-level rise during the Holocene (c. 8,000 years ago) provided hydrological reconnection between the Pacific and Indian Oceans via numerous straits across the Malay Archipelago. Even though at present both the Pacific and Indian Oceans are connected, genetic differentiation detected between populations from the east and west of the Malay Peninsula in coastal and marine species bears witness to this historical vicariance (Adibah, Ng, & Tan, 2015;Antoro, Na-Nakorn, & Koedprang, 2006).…”

DNA barcoding of Malaysian commercial snapper reveals an unrecognized species of the yellow-lined Lutjanus (Pisces:Lutjanidae)

“…DNA was extracted following the CTAB extraction method [ 22 ]. PCR amplification of the CO1 locus was performed using combinations of primers F1, F2, R1 and R2 [ 23 ] in 25.0 μl reaction volumes including 8.37μl molecular grade water, 1.25μl 10X PCR buffer, 1.0μl of MgCl 2 (25mM), 0.25μl of each primer (10mM), 0.5μl of Intron i -Taq ™ plus DNA Polymerase (5U/μl) and 0.75μl of template DNA.…”