A moderately large (4.5-5.5mm) ‘picture-winged’ barkfly. Uncommon in Britain and Ireland.
Forewing has six distinct spots in the apical cells. T. sexpunctatum is often (but not always) distinguished from the similar T. majus by the presence of a conspicuous patch near the centre of the discoidal cell.
Female
Subgenital plate forms a ‘Y’ shape and lacks colourless stripes on the apical lobe (cf. T. majus). Compare with similar species
Male
The hypandrium (apex of the abdomen) has a characteristic thin appendage on the right hand side. It lacks dark areas on the epiproct (cf. T. majus). Compare with similar species