Spots, icons, ding bats, secondaries, less than half a page or smaller, while working on smaller assignments I've heard them called many things. The do present their own set of unique demands, and are usually swimming in type. Here's some of my recent efforts. The illustrations below printed less than half a page;
For Popular Science magazine. Protecting your smart phone from viruses. Art director; Matt Cokeley. Oils on paper.
For Motor Trend magazine. Politics in the automobile industry. Art director; Andy Foster. Vector artwork
For Motor Trend magazine. Viruses in a car computer systems. Art director; Darren Scott. Vector artwork.
Above - Icons for article about jobs with a future in Germany. For the magazine; Wirtschafts Woche, art director; Holger Windfuhr. Vector - artwork