A new species of Prosimulium (Diptera: Simuliidae): an interchange as a primary reproductive isolating mechanism?

Abstract

A previously undescribed species of the IIIL-1 group of Prosimulium differs from P. mixtum, its nearest relative, principally by a whole-arm interchange. It shares the sex chromosomes of P. mixtum, and an X chromosome and autosomal polymorphism. It is apparently a very local species (Center County, Pennsylvania [USA]) that differs from P. mixtum in larval habitat preference and other aspects of its biology. It is argued that the interchange provided a chromosomal basis for reproductive isolation between P. mixtum and the new species, which progressively diverged in biology and mating system.