The apical margins of the anal sternite and ventrite together with the posterior margins of laterosternites form small, transverse, vertical, usually elliptical or rectangular plate, so called “anal plate”.
Jewel Beetles
Buprestidae Leach, 1815
(after Hangay & Zborowski 2010): Body elongate, bullet-shaped, with a rigid body. Approximately 1.5-60mm in length. Distinctive colouration, often metallic, especially on the ventral surface. Head hypognathous, antennae short and serrate, 11-segmented. Tarsal formula 5-5-5, with ventral membranous lobes on segments 1-4.
Here is a great photographic guide to the Jewel Beetles of South Australia by Peter J. Lang: syzygium.xyz/buprestidae/introduction.php.
Publications
Hangay G, Zborowski P (2010): A Guide to the Beetles of Australia. CSIRO Publishing, Collingwood, Australia.