Atalantycha bilineata was originally described by American entomologist Thomas Say in 1823 under the binomial name Cantharis bilineata in the Journal of the Academy of Natural Sciences of Philadelphia (volume 3, page 182):
6. C. bilineatus. Rufous; elytra black; thorax with two black lines. Inhabits the United States.
The eagle-eyed will note that Say indicates the species as C. bilineatus, not C. bilineata. Why you ask, well, the discrepancy arises from the gender of the species name, which must agree with the genus name Cantharis (feminine). While it was sometimes historically listed with the masculine suffix -us, the correct scientific name based on ICZN rules is Cantharis bilineata.
The species had kept the Cantharis bilineata name until 2005 when Sergey Kazantsev's review of the genus established the new Nearctic genus Atalantycha to accommodate certain species, including A. bilineata as a new combination.