An Overview of Aquatica Fu et al., a Phylogeny of Aquatic Fireflies Using Mitochondrial Genomes, a Description of Two New Species, and a New Record of Aquatic Fireflies in China (Coleoptera: Lampyridae: Luciolinae) †.

Simple Summary: When we refer to aquatic fireflies, we are actually referring to their larvae, as the adults are free-flying. Many species of fireflies have been collected from terrestrial specimens only and may not have any information to indicate the larval habitat. The ideal situation is to rear specimens from eggs laid, but this is a difficult venture and is not always successful. More recently, the use of molecular genetics, especially the genome of the mitochondrion, has enabled us to match larvae with adults with great confidence. Here, we address two new species of aquatic fireflies from China where the aquatic association is confirmed, and the relationships of these species with other aquatic fireflies are established. There are now seven species in the genus Aquatica Fu & Ballantyne, with all but one known from the characteristics of males, females, and larvae. Molecular information is combined with morphological taxonomy for the delimitation of both genus and species. The monophyly of the genus Aquatica is strongly supported in six trees, and its position as sister to the genus Nipponoluciola Ballantyne Kawashima Jusoh et Suzuki is stable across maximum likelihood and Bayesian inference results. Two new species of Aquatica Fu & Ballantyne, A. qingshen sp. nov. and A. xianning sp. nov., described from the features of males, females, and larvae, are closely related within a single clade within the genus Aquatica. Females have distinctively shaped median oviduct plates. A Chinese population identified as A. lateralis was found to be morphologically similar to the Japanese population, but genetic distances suggest that it is a distinctive species. No larvae are associated with this species. Definitions of the aquatic status of Luciolinae fireflies are expanded. [ABSTRACT FROM AUTHOR]