深海生物ダイオウグソクムシ死ぬ　世界初の完全脱皮ならず―三重・鳥羽水族館

　三重県鳥羽市の鳥羽水族館は１０日、飼育中の深海生物ダイオウグソクムシが死んだと発表した。今年１０月には世界で５例目となる体の後半部の脱皮が確認され、前半部も脱皮すれば世界初だった。死因は不明で、同館は今後、解剖を実施する。
　同館によると、ダイオウグソクムシはダンゴムシなどの仲間で、体の後半部を先に脱皮する習性がある。死んだダイオウグソクムシはメキシコ湾で採集されたオスで、２０１４年５月末から飼育され、体長約３０センチ、体重は約１キロ。１０月に後半部のみ脱皮した。
　同館の担当者は「世界初の体の前半部の脱皮を期待していたので、本当に残念」と話した。（2019/12/10-15:26）

A rare deep-sea crustacean at an aquarium in Japan has died, before what would have been the world's first confirmation of the creature fully shedding its old exoskeleton, the aquarium said Tuesday.
   The male giant isopod at Toba Aquarium in the central prefecture of Mie was confirmed in October to have shed the back half of its old exoskeleton, only the fifth such instance ever confirmed in the world. It died before shedding the front half.
   The cause of death is unknown, and the aquarium in the city of Toba plans to conduct an autopsy. The aquarium began raising the male giant isopod, collected from the Gulf of Mexico, in late May 2014. It was roughly 30 centimeters long and weighed about a kilogram.
   "We were expecting the world's first observation of the shedding of the front half of its body, so it's death is really regrettable," an official of the aquarium said.
   The giant isopod is related to the woodlouse and has the tendency to begin shedding its old exoskeleton from the back half of its body, according to the aquarium.