title: Offshore spawning of Conger myriaster in the western North Pacific: evidence for convergent migration strategies of anguilliform eels in the Atlantic and Pacific.
abstract: The spawning area of the common Japanese conger, Conger myriaster, had remained unknown because spawning adults or its newly hatched larvae were never collected. Using genetic identification, we determined that C. myriaster spawns far offshore in the western North Pacific, just west of the spawning area of the Japanese eel, Anguilla japonica. In June 2008, six newly hatched C. myriaster larvae, 5.6-6.9 mm, were collected at the eastern edge of where many small unidentified Conger leptocephali (7-20 mm) were collected previously. The offshore spawning location of C. myriaster is analogous to that of the American conger eel, Conger oceanicus, and the American eel, Anguilla rostrata, in the Sargasso Sea, suggesting that convergent evolution of large-scale reproductive migration strategies in both anguillid and conger eels has occurred in the north Atlantic and Pacific subtropical gyres. The realization that two anguillids, A. rostrata and A. japonica, and two congers, C. oceanicus and C. myriaster, have evolved almost identical migration strategies in widely separated ocean basins suggests that natural selection for larval survival and recruitment success has resulted in long offshore spawning migrations in two phylogenetically distant taxa of anguilliform eels.
authors.affiliation: Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8564, Japan. miller@aori.u-tokyo.ac.jp
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Miller
authors.forename: Tatsuki
authors.initials: T
authors.lastname: Yoshinaga
authors.forename: Jun
authors.initials: J
authors.lastname: Aoyama
authors.forename: Tsuguo
authors.initials: T
authors.lastname: Otake
authors.forename: Noritaka
authors.initials: N
authors.lastname: Mochioka
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kurogi
authors.forename: Katsumi
authors.initials: K
authors.lastname: Tsukamoto
mesh_terms: D025041:Animal Migration / Q000502:physiology*; D000818:Animals; D001267:Atlantic Ocean; D004524:Eels / Q000235:genetics / Q000502:physiology*; D003576:Electron Transport Complex IV / Q000235:genetics; D010140:Pacific Ocean; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D012336:RNA, Ribosomal, 16S; D003576:Electron Transport Complex IV