Life Cycle of the Phyline Plant Bug Conostethus americanus Knight, 1939 (Hemiptera: Heteroptera: Miridae) in Native Mixed-Grass Prairie in Wyoming, USA

Abstract

The life cycle of the phyline plant bug Conostethus americanus Knight 1939 (Hemiptera: Heteroptera: Miridae: Phylinae) is described from native mixed-grass prairie in southeast Wyoming. The bug is monophagous, univoltine, and overwinters as eggs in tufts of its host, Sandberg bluegrass (Poa secunda J. Presl, Poaceae). Eggs are laid in the host’s leaf sheaths and occasionally along the rib of wilted leaves. The eggs hatch in April, coinciding with the host’s first spring leaf growth. During the daytime, older nymphs (instars III–V) and recently molted adults are typically found on bare ground, adjacent to the host tuft crowns. After dark, the nymphs and recently molted adults climb onto the leaves to feed. The first adults appear in early May. Males outnumber females 1.5:1. Mating and oviposition occur during the latter half of May and early June. The distribution of C. americanus and its host are mapped. Seasonality is described. Host specificity and habitat affinity, which prevent competition with the ubiquitous Labops hesperius (Hemiptera: Heteroptera: Miridae), are discussed. Photographs of adults, eggs, nymphs, host feeding damage, and habitat are provided.