Coccinellidae wide variety of beetle species in other families as "ladybirds", i.e. coccinellids. Beetles are particularly prone to such misidentification if they are spotted in red, orange or yellow and black. Examples include the much larger scarabaeid grapevine beetles and spotted species of the Chrysomelidae, Melyridae and others. Conversely, laymen may fail to identify unmarked species of Coccinellidae as "ladybirds". Other beetles that have a defensive hemispherical shape, like that of the Coccinellidae (for example the Cassidinae), also are often taken for ladybirds. A common myth, totally unfounded, is that the number of spots on the insect's back indicates its age.
Backus–Naur form One common feature of many variants is the use of regular expression repetition operators such as codice_19 and codice_20. The extended Backus–Naur form (EBNF) is a common one. Another common extension is the use of square brackets around optional items. Although not present in the original ALGOL 60 report (instead introduced a few years later in IBM's PL/I definition), the notation is now universally recognised. Augmented Backus–Naur form (ABNF) and Routing Backus–Naur form (RBNF) are extensions commonly used to describe Internet Engineering Task Force (IETF) protocols. Parsing expression grammars build on the BNF and regular expression notations to form an