The family Convolvulaceae in the Tertiary of Australia: evidence from pollen

Abstract

A study of fossil and modern pollen of the family Convolvulaceae is presented and five fossil types are identified. Two types, one a large tricolpate of the form species Perfotricolpites digitatus, with similarities to Convolvulus, Operculina and probably other genera, and the second, a small tricolpate, Tricolpites trioblatus, with affinities to Wilsonia and possibly Cressa, first appear in the late Eocene of southern Australia. Fossil pollen is found worldwide, with the oldest occurrence being Calystegiapollis microechinatus from the early Eocene of Africa. Perfotricolpites digitatus first appears in the mid-Eocene of Brazil, and specimens similar to P. digitatus from Antarctica suggest that it migrated into Australia by the Antarctic route. Wilsonia is endemic to Australia today, but it was in New Zealand in the mid–late Miocene.