Sex or Fission? Genetics Highlight Differences in Reproductive Strategies of Two Sympatric Fissiparous Sea Cucumber Species in Reunion Island (Southwestern Indian Ocean)

Holothuria leucospilota and Stichopus chloronotus are among the most widespread tropical sea cucumber species usually harvested for food medicine in Asian countries, which natural stocks have collapsed worldwide. Both can reproduce sexually asexually, a better understanding of their reproductive strategy provide useful information conservation purposes. To describe genetic structure diversity sympatric populations from these space time, individuals were sampled over different sites seasons Reunion Island (Southwestern Indian Ocean). They genotyped using 24 9 specific microsatellite markers H. S. chloronotus, respectively. Multi-locus genotypes (MLG) lineages (MLL) identified, analyses population performed seasons. No repeated MLG nor MLL found leucospilota, demonstrating absence asexual reproduction. Populations not genetically differentiated, acting as metapopulation, with larval exchanges within reef. Contrarily, MLGs all differentiated. Asexual reproduction seems to reach high level this (mean clonal richness = 0.24). For both species, was stable through Thus, fissiparous use two strategies reproduction, may allow them reduce interspecific competition.