Xylonichnus trypetus Genise, 1995

Diagnosis: Longitudinal borings at different depths inthe xylem, interconnected by tangential tunnels. Crosssections of borings are rectangular; with rounded cornersand extremely flat; the height approximately one-fourththe width. Borings have an outer layer and are filled withfrass that is mostly separated in packages, or has meniscusstructure. Borings are in permineralized wood of a con-ifer, which exhibits well-preserved cellular structure.