[1] HARVARD UNIV, DEPT ORGANISM & EVOLUTIONARY BIOL, CAMBRIDGE, MA 02138 USA
[2] UNIV HAMBURG, INST ZOOL, D-20146 HAMBURG, GERMANY
[3] UNIV HAMBURG, ZOOL MUSEUM, D-20146 HAMBURG, GERMANY
[4] UNIV MAINE, DEPT BIOCHEM MICROBIOL & MOLEC BIOL, ORONO, ME 04469 USA