Abundance and Diversity of Urban Ant Species (Hymenoptera: Formicidae) and Water Relations of the Kudzu Bug (Hemiptera: Plataspidae)

Abstract

Insect pests are heterogeneous group of organisms characterized by the fact that they damage or otherwise adversely affect people or their property. These insects cause pain, annoyance, disfigurement, emotional distress, disability, and damage because of bites, sting, feeding on humans. In fact, urban areas are extremely well suited for groups of insects that have associated with their lives with human and their activities. Ants (Hymenoptera: Formicidae) are among the most dominant group of insects and constitute significant biomass in a variety of ecosystems. Their economic effects on human health, property, and biodiversity make them a subject of interest. Temporal variation in temperature, rainfall and water availability are among the important factors governing the abundance and diversity of species within a locality. In the same vein, the kudzu bug, Megacopta cribraria, is also a nuisance urban pest species as well as an agricultural pest. Desiccation is a crucial stressor and plays an important role in insect survival, growth, development, behavior, and ultimately distribution. The management of these species is partially dependent on understanding these aspects of their physiology. Thus, the primary objectives of the research with urban ants were to: (1) investigate the seasonal abundance and diversity of ant species around homes in Lee County, Auburn, Alabama; (2) determine the influence of seasonal conditions on the abundance and diversity of ant species. Between June 2018 and June 2019, field study was conducted to understand the population dynamics of ant species in Auburn, Alabama. The field study resulted in a total of 16 ant species belonging to 13 genera in four subfamilies being identifıed. Across seasons, Argentine ant, Linepithema humile, big headed ant, Pheidole dentigula, and red important fire ant, Solenopsis invicta were most abundant. The greatest species diversity was in early September and lowest was in early March. The abundance and diversity of nuisance ant species is seasonal and species interaction dependent. In laboratory experiment with M. cribraria, the primary research goals were to: (3) determine the total body water content (%TBW content), rate of mass, total body water loss (%TBW loss), and cuticular permeability (CP) of adult and nymphal M. cribraria, and to determine the desiccation sensitivity of all stages of kudzu bug. First instar nymphs from generation one had significantly greater %TBW than the other instars and across generations whereas generation two fifth instars had the lowest %TBW. The CP value of adult female generation one was the greatest across generations. In addition, when the mass losses of nymphs were compared, generation one first instars had the greatest mass loss compared with other instars across generations whereas overwintered generation two adult females had the lowest mass loss across generations. This study will aid in understanding how environmental stress may affect the survival and relative abundance of M. cribraria in fields and around homes. Collectively, these studies give insight into physiology of the insects that can be leveraged to for control.

Key words: integrated pest management, physiology, urban pest, soybean pests, invasive pest.