The size and seasonal distribution of the sibling species Tabanus nigrovittatus and Tabanus conterminus in New Jersey (Diptera: Tabanidae)

Coastal salt-marsh tabanids have an important economic impact on agricultural and recreational industries in New Jersey, because of their degree of penetration inland, persistence in seeking hosts, biting severity and breadth of host range. The seasonal activity patterns were studied of a pair of cryptic species, Tabanus nigrovittatus and T. conterminus, which can be differentiated completely by means of protein electrophoresis. T. conterminus, which was slightly larger, was most abundant in box trap catches in mid-July, and its oviposition period was confined to that month, while T. nigrovittatus was more abundant throughout the year and its numbers declined more gradually, which suggested the possibility of more than 1 generation a year. It is concluded that general control programmes against flying adult tabanids would affect T. conterminus more than T. nigrovittatus.