I don’t know if it should be considered a subgenre of Old-Time or if it’s a category unto itself, but there’s a subset of mandolin-friendly tunes that
This early 1900’s string band ragtime music is represented on the recordings of Adam Tanner, the Ragtime Skedaddlers, The Old 78’s, Leroy Larson, Kenny Hall, The Hot Seats and The Skirtlifters, to name a few somewhat recent examples. In written form, many of these rags, cake walks, stomps and marches are featured in Steve Parker's Ragtime for Fiddle and Mandolin book. In Irish music, the type of tune called a barn dance can also have some ragtime elements.
I do feel like these string ragtime numbers are distinct from the kind of music played by Eddy Davis, Cynthia Sayer, Elmer Snowden, Don Vappie, Tim Allan, Narvin Kimball, Buddy Wachter, Tyler Jackson, Carl LeBlanc and other jazz tenor banjo players. Nonetheless, some knowledge of the chordal Dixieland jazz banjo style of playing cannot hurt when learning these ragtime tunes. It is the quest and use of other ideas that round you out as a musician, and I’m not too strict with regard to one style or another. Adding some of these ragtime tunes to my repertoire would be a nice challenge and complement to the Irish and Old-Time tunes I already play and they would be great for tenor banjo.