The species was named for Larry, the Chief Mouser to the Cabinet Office at the British Prime Minister's residence at 10 Downing Street.

[3] A group of Caccothryptus specimens were collected in 1953 by forester Harry George Champion in the Haldwani division of the Kumaon Himalayas, India.

In 2021, Natural History Museum entomologist Keita Matsumoto identified a number of distinct species from these specimens.

C. larryi was placed in the species group compactus and named for Larry, a cat serving as Chief Mouser to the Cabinet Office at 10 Downing Street since 2011.

The beetle's head, smooth and punctured, is slightly retracted into its pronotum, and features eleven-segment antennae.