By Borja Suarez ARGUINEGUIN, Spain (Reuters) – Spain’s sea rescue service on Wednesday picked up more than 300 migrants trying to reach the Canary Islands in rickety boats, with nine of them clinging to a semi-sunken dinghy. The rescue service said it was unaware of any drownings as reported by a rights group. Helena Maleno, founder of the Walking Borders migration monitoring group, said 18 people had died trying to make the perilous crossing to the island of Lanzarote from Africa. Reuters could not confirm that figure independently. The rescue service said on its Twitter account 319 migrants …