Fig. 3
From: Host-specific leaf-mining behaviour of holometabolous insect larvae in the early Permian
Thin sections of Asteronomus maeandriformis in Autunia conferta from Crock, Thuringian Forest Basin, Germany. (a) Section through an Autunia conferta leaf (MB.Pb.1979/0188) with frass trail (box). The scrolled margins indicate the upper side of the pinnule. (b) Section through the frass trail in (a). Note the upper epidermis (arrow), which covers the tunnel. (c) Another example of a compressed tunnel in the upper parenchyma covered by the upper epidermis (arrow) (MB.Pb.1979/0179). (d) Transverse and longitudinal sections through endophytic frass trails in Autunia conferta (MB.Pb.1979/0188). (e, f) Longitudinal section through a frass trail (MB.Pb.1979/0069). Note the calcite-filled cracks and the thin calcite cover on the upper side of the leaves from shrinkage of the organic matter in (arrows in f).
