Tenor horn or what?

My publishers and I settled on tenor horn for the Moretone session – even if Leppe Sundewall usually has been listed playing bass trumpet. The Swedish Jazz Discography on line says btp – but on the other hand claims that he played th, tenor horn, in the 1949 James Moody sessions. Photographs show him playing a bass trumpet during those recordings! On one photo from the Moretone session he seems to hold a tenor horn, which resembles a thin, small tuba. The sound, however, is very similar from the two horns.
Lennart "Leppe" Sundewall played the trumpet as well as the two bigger horns, one octave lower than the trumpet, and also appeared as a singer and showman under the name Lou Sandy.