On August 5, 2016, two epibiotic species, the turbellarian Ectoplana limuli (Ijima & Kaburaki, 1916) and the goose barnacles Octolasmis neptuni (MacDonald, 1869), were found on two adults of the Japanese horseshoe crab Tachypleus tridentatus (Leach, 1819) in Hiroshima Prefecture. On September 20, 2017, the carcass of a juvenile horseshoe crab was found, which had presumably been eaten by a bird.