T. piceatum has white petioles with green wings but the mid-rib above is coloured darker, and the bracts are heavily built, spreading with upturned apices and suffused leaden-purple. Amongst its close relatives in the Piceata group which share these features, it is distinguished by ligules with pinkish stripes and darker teeth, and leaves with 3-4 patent side-lobes which are heterophyllous, the inners producing a large triangular end-lobe with an extenuate apex.