Up front I must state that this is not a confirmed identification.
There are two leaftails with only two pale stripes on the side of the thorax in Costa Rica. These require examination of the appendages to separate. That determination is clearly not possible from my very poor photograph taken at a distance with a 2X converter, which I am including for the sake of completeness. The ranges of existing observations, however, might suggest that the one I saw at Rincón de la Vieja Volcano might most likely be P. bifasciatus. This, quite correctly, is not good enough for iNaturalist.
| male |
 male.jpg) |