  A polygon $P$ is called a reptile, if it can be decomposed into $k\ge 2$
nonoverlapping and congruent polygons similar to $P$. We prove that if a cyclic
quadrilateral is a reptile, then it is a trapezoid. Comparing with results of
U. Betke and I. Osburg we find that every convex reptile is a triangle or a
trapezoid.
