Evolutionary origin of squamiform microsculpture on the forewing-holding devices (frenae) in Heteroptera

摘要

Frenae are forewing-holding ridges situated in the Heteroptera parallel to the lateral sides of mesoscutellum, and covered by a squamiform, overlapping, glabrous microsculpture. The situation found in Rectilamina sp. (Dipsocoromorpha: Schizopteridae: Hypselosomatinae) suggests that each single squamiform element is homologous to a strongly modified microtrichium, and that, at least in this case, there is no basic difference between microtrichium and acanthus.