First Report on Life History Parameters of Thripsaphis ballii (Gillette) on Shoreline Sedge (Cyperaceae) in Oklahoma Wetlands

Abstract

Thripsaphis ballii (Gillette) aphids were first collected on Carex hyalinolepis Steudel plants in a restored wetland along the Deep Fork River in Lincoln County, OK, in 2015. Little is known about the species. A controlled study documented selected life history parameters at 28°C. T. ballii developed through four nymphal instars before the last molt into an adult. Total nymph development averaged 10.6 days, and average duration of each instar ranged from 2.38–2.88 days with more time spent as first and fourth instars. Mean pre-reproductive period for adults was 0.9 day, while reproductive period averaged 11.2 days in which females produced an average of 19.4 nymphs. Longevity (birth to adult) averaged 22.6 days. First and second instars had five antennal segments and third instars through adults had six segments. Based on morphological measurements, second through fourth instars and adults can be discerned based on a combination of body length, number of antennal segments, and antennal length. Information from the study provides the first recorded life history parameters for the species, as well as the first documentation of its occurrence in Oklahoma.