Relationship between female size, type of egg mass deposited, and description of the oviposition behavior of the sibling species Tabanus nigrovittatus and T. simulans (Diptera: Tabanidae)

In studies on 2 sibling species of tabanids on a salt marsh in Massachusetts, smaller flies (referable to Tabanus nigrovittatus Macq.) deposited double-tiered egg masses on the adaxial surface of leaf blades of Spartina alterniflora while orienting themselves on the leaf blade with their heads directed towards the marsh surface. Larger females (referable to T. simulans Wlk.) deposited single-layered shingled eggs with their heads oriented towards the sky. T. simulans was observed in both the laboratory and field, but T. nigrovittatus only in the laboratory.