A New Genus and Species of Crambinae (Pyraloidea: Crambidae) with Brachypterous Females from Colorado, U. S. A.

The genome of Coloradactria frigida was sequenced at low coverage to recover six genes and integrate them into a broader phylogenetic context from a previous study on Crambinae; the tree obtained is presented. Genus Neodactria B. Landry is the closest relative to Coloradactria frigida. Additional keywords: Coloradactria frigida, Crambini, Neodactria, genome sequencing, phylogeny The Crambinae, now most often placed in Crambidae (Pyraloidea), are distributed worldwide and presently include 2140 species in 177 genera (Nuss et al. 2024) (as of Dec. 9, 2024).

In North America north of Mexico, Crambinae now include 200 species in 37 genera (Hayden & Scholtens 2023). The group is divided into seven tribes (Léger et al. 2019), of which the Crambini is the most diverse, with 63.5% of the species of Crambinae in North America. ADW encountered an unfamiliar crambine on 4 November, 2023, at a site near his residence in Castle Pines, Douglas County, Colorado.

Despite the very late date for Lepidoptera activity, and that there had been a significant cold snap with snow a week earlier, the moth was very abundant, as 46 were collected and over 100 were seen that afternoon (14:30–16:30 hrs), all in a very small mowed area roughly 10 m by 15 m. Almost all individuals were in fresh condition. This population was studied for the following three weeks, with the last male seen on 22 November.

A few solitary individuals were found at nearby sites during this study period. Exhaustive searches of Colorado pyraloids on iNaturalist beginning in December, 2023, identified several additional sites for the moth; one of which was surveyed in 2024, where the moth was found in extraordinary abundance, as detailed below.