||Hunt T et al., A comprehensive phylogeny of beetles reveals the evolutionary origins of a superradiation. Science. 2007 Dec 21 318(5858):1913-6. DOI: 10.1126/science.1146954 p.1913 left columnPubMed ID18096805
|| R. A. Crowson, The Biology of Coleoptera (Academic Press, London, 1981).  D. Grimaldi, M. S. Engel, Evolution of the Insects (Cambridge Univ. Press, Cambridge, 2005).
||P.1913 left column: "The extraordinary diversity of beetles has long fascinated evolutionary biologists (ref 1). The strongly sclerotized front wings defining the order Coleoptera (the beetles), which provide protection while retaining the ability of powered flight with the membranous hindwings, may be an evolutionary novelty that promoted extensive diversification (primary source 2). Beetles appeared around 285 million years ago (Ma) (primary sources), followed by radiations of wood-boring (suborder Archostemata), predacious (Adephaga), and fungivorous (Polyphaga) lineages (ref 4) present in the fossil record from the middle Triassic on (primary sources)."