only copy index if exists
only copy index if exists

wgerlach/Shock,teharrison/Shock,MG-RAST/Shock,wgerlach/Shock,wgerlach/Shock,teharrison/Shock,teharrison/Shock,MG-RAST/Shock,MG-RAST/Shock,teharrison/Shock,MG-RAST/Shock,MG-RAST/Shock,wgerlach/Shock,teharrison/Shock,wgerlach/Shock,teharrison/Shock