The Trichoptera of Panama. XIX. Additions to and a review of the genus Leucotrichia (Trichoptera, Hydroptilidae) in Panama

Prior to 2016, three species of caddisflies in the genus Leucotrichia (Trichoptera: Hydroptilidae) were known from Panama. Subsequently, one new species and four new country records were added to Panama’s fauna. Herein, four new species are described (Leucotrichiacortaderasp. nov., L.holzenthalisp. nov., L.lumasp. nov., L.ruiterisp. nov.) and two new country records added for Panama (L.botosaneanui Flint, 1996, L.hispida Thomson & Holzenthal, 2015). The resulting total of 14 species makes Panama the most species-rich country for this genus. Panama’s species assemblage is most similar to Costa Rica and Mexico. However, the similarities among faunas in all these countries is very low (< 35%). Thus, more new country records are possible with additional collecting. Recent collections (2015–2021) of new caddisfly species and country records in this genus were effected primarily by use of Malaise traps. Our collections also evidenced multiple species from the same collecting site, with seven species each found in both lowland and mid-altitude sites. Investigation of the distribution of Leucotrichia species with altitude reveals a preference by several species for higher altitude locations. Additional Malaise trap collections over extended time periods are needed to verify the validity of all observations and preliminary conclusions made to date.