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From whole body extracts of Photuris versicolor fireflies, the defensive betaine N-methylquinolinium 2-carboxylate (1) was isolated and characterized on the basis of spectroscopic data and comparison with a synthetic sample.

The quinonoid defensive spray of 2 carabid beetles of the subfamilies Metriinae and Paussinae is ejected hot (55°C and 65°C), with a heat content of 0.19 and 0.17 cal/mg. Hydroquinone(s) and hydrogen peroxide are identified as precursors of the quinones, indicating that in these lesser known ‘bombardier beetles’ the explosive discharge mechanism is similar to that of the familiar bombardiers of the genusBrachinus(subfamily Carabinae, tribe Brachinini).

The aposematic cantharid beetle Chauliognathus leconteiproduces a defensive secretion, from glands in its thorax and abdomen, containing 8- cis-dihydromatricaria acid. Similar acetylenic compounds are known only from certain fungi and flowering plants.

A television camera, like the eyes of some insects, is sensitive to ultraviolet light. When equipped with an appropriate ultraviolet-transmitting lens, such a camera can be used for the direct examination of ultraviolet reflection patterns (for example, on flowers, butterflies) that are invisible to us, but visible to insects.

Males of the queen butterfly Danaus gilippus berenice, deprived of the two extrusible brushlike "hairpencils" at the rear of their abdomen, are capable of courting females but incapable of seducing them. In normal courtship, an aphrodisiac secretion associated with the hairpencils is transferred by way of tiny cuticular "dust" particles to the antennae of the females. Of the two substances identified from the secretion, one (the ketone) acts as the chemical messenger that induces the females to mate. The only known function of the other compound (the diol) is to serve as a glue that sticks the dust to the female. Males were reared under conditions in which they produced subnormal amounts of ketone and showed reduced seductive capacity. Under certain experimental circumstances, the competence of these males was restored by addition of synthetic ketone.

The cyanogenic secretion of the polydesmoid millipede Apheloria corrugata(Wood) is discharged from paired, serially arranged glands, each consisting of two compartments. In one compartment is stored an undissociated cyanogenic compound, and in the other, a chemical factor that triggers cyanogenesis. The gland is constructed in such a way that the contents of the two compartments are mixed, and cyanogenesis is initiated, at the very instant of discharge. The stored cyanide precursor may be mandelonitrile.

Three species of gyrinid beetles (Gyrinus ventralis, Dineutes hornii, and D. serrulatus) have been found to produce the nor-sesquiterpenoid aldehyde gyrinidalin the secretion of their pygidial defensive glands. This highly functionalized terpene is shown to be (E,E,E)-3,7-dimethyl-8,11-dioxo-2,6,9-dodecatrienal on the basis of spectral evidence and chemical degradation. While a very wide range of sesquiterpenoid structures occur in nature, gyrinidal appears to be the most highly oxidized acyclic sesquiterpene known.

Two new defensive steroids (lucibufagins6and7) and a fluorescent pterin (8) have been isolated and characterized from the fireflyPhotinus pyralis.

The defensive secretion of the “daddy longlegs” Leiobunum vittatumwas analyzed and found to contain the acyclic ketones 4-methylheptan-3-one and E-4,6-dimethyl-6-octen-3-one as its major organic components. Although 4-methylheptan-3-one has been found previously as an alarm substance in certain ant genera, the second component, whose structure is confirmed by synthesis, is new.

The larva of the tineid moth Ceratophaga vicinella is a scavenger that feeds on the keratin plates of dead gopher tortoises (Gopherus polyphemus) in south Florida. The larva makes a multilayered silk tube that extends over part of the shell and into the sandy soil beneath. The mature pupa appears to ratchet its way up the tube by using abdominal spines. Ceratophaga larvae are the only insects that are able to subsist on a diet of solid, dry keratin. The genus Ceratophaga is primarily African; C. vicinella, the only New World species, is possibly a remnant of a more widespread lineage. Unless C. vicinella has another, unknown dietary resource, it is almost certainly an endangered species.