Wingspan 10-13 mm.
One of several related and rather similar species which can be difficult to separate as adults without reference to the structure of the genitalia. S. pyrella is generally a little smaller and darker than its congeners, and has a rufous tinge to the wingtip.
It is a common species throughout most of Britain and Ireland, except in the far north, and flies in two generations, during May and August.
The larvae feed on hawthorn (Crataegus), apple (Malus) and pear (Pyrus), and like several related species, live under a slight web on the upper surface of a leaf. They are quite distinctively marked in yellow and brown.