Petiole (insect anatomy) a pedicel, but in entomology, that term is more correctly reserved for the second segment of the antenna; while in arachnology, 'pedicel' is the accepted term to define the constriction between the cephalothorax and abdomen of spiders. The plump portion of the abdomen posterior to the petiole (and postpetiole in the Myrmicinae) is called the gaster. The structure of the petiole is an easy way to visually classify ants, because the major subfamilies of Formicidae have structural differences: some ants have two-segmented petioles, while others have a single-segmented petiole. Petiole may also be used in the context of wing veins,
Bookworm (insect) soft-bodied wingless Psocopterans (usually "Trogium pulsatorium"), which feed on microscopic molds and other organic matter found in ill-maintained works (e.g., cool, damp, dark, and undisturbed areas of archives, libraries, and museums), although they will also attack bindings and other book parts, making the booklouse not a true louse. By the 20th century, modern bookbinding materials thwarted much of the damage done to books by various types of book-boring insects. Bookworm (insect) Bookworm is a popular generalization for any insect that is said to bore through books. True book-borers are uncommon. Two types of moths, the common clothes moth and the