Evaluation of ultra-low volume treatments on Culex quinquefasciatus (Diptera: Culicidae) abundance and relative age by parity dissection.

St. Tammany Parish Mosquito Abatement District relies on ultra-low volume (ULV) insecticides to manage adult Culex quinquefasciatus (Say 1823), the primary vector of West Nile virus in Louisiana, but abundance rarely declines post-treatment. Three field ULV applications each of adulticides containing deltamethrin, naled, or resmethrin were conducted from May through October 2022 to measure efficacy against free-flying Cx. quinquefasciatus. Female mosquitoes trapped before and after treatment were identified, counted, and age-graded by parity dissection. No insecticide applications reduced Cx. quinquefasciatus abundance, but trials with deltamethrin and naled significantly lowered average mosquito age in the area post-treatment. No trials with resmethrin reduced mosquito age, which corroborates laboratory susceptibility data indicating local resistance toward the pyrethroid. These trials establish parity dissections and relative age gradation as a means of measuring treatment success against Cx. quinquefasciatus.

First Record of Aedes Japonicus in St. Tammany Parish, Louisiana.

Information of species presence and abundance is useful for taking a targeted approach to controlling populations of medically important and nuisance mosquito species. In April 2023, staff at St. Tammany Parish Mosquito Abatement District (STPMAD), in Slidell, Louisiana, identified Aedes japonicus (Theobald, 1901) mosquitoes from a larval sample brought in from the field for identification. Although invasive Aedes species like Aedes albopictus are commonly found in Louisiana, this is the first record of Ae. japonicus in St. Tammany Parish.

FIRST RECORD OF AEDES JAPONICUS IN ST. TAMMANY PARISH, LOUISIANA.

Information of species presence and abundance is useful for taking a targeted approach to controlling populations of medically important and nuisance mosquito species. In April 2023, staff at St. Tammany Parish Mosquito Abatement District (STPMAD), in Slidell, Louisiana, identified Aedes japonicus (Theobald, 1901) mosquitoes from a larval sample brought in from the field for identification. Although invasive Aedes species like Aedes albopictus are commonly found in Louisiana, this is the first record of Ae. japonicus in St. Tammany Parish.