NEW REPRESENTATIVES OF PREDATORS IN BURMITE: A TINY MANTID, A DAMSEL BUG, AND A LARVAL MEGALOPTERAN

Amber from the southeastern Asian nation of Burma, called burmite, has been known and used for over a thousand years, mostly as a source for decorative artifacts. Its biological inclusions have only been studied scientifically over the last several decades. Being placed in the Lower Cretaceous (Upper Albian, 112.2 to 98.9 Ma), burmite provides a means to examine one of the most important periods in the evolution of terrestrial arthropods. Between the two major collections of burmite (the Natural History Museum in London and the American Museum of Natural History in New York), nearly 4200 arthropods have been recorded. In addition to these, several private collections also house specimens, some of which contain rare inclusions available for professional study. Several of these unique inclusions from a private collection are presented.

Predator-prey relationships play a key role in the evolution of life on earth. Several predators from burmite have been examined, ranging from the tiny, to the long beaked, to the large and fast. Comprising the extremely small, a 1 mm mantid (Mantodea) was examined. Though this first instar mantid nymph is incomplete, intricate details of the head and forelegs are clearly visible. A 3 mm Damsel bug (Hemiptera: Heteroptera: Nabidae) was recently found that possesses a nearly 2 mm long proboscis. The entire piercing stylet is visible and can even be seen to extend beyond the proboscis. Raptorial tarsal claws are present on all its appendages and all of the femora are also slightly thickened. Tiny spines are present on the first two pair of appendages. All of these suggest this organism was well-equipped to kill. Perhaps one of the most amazing burmite specimens ever found is a 4 mm head of a larval Dobsonfly (Neuroptera: Megaloptera: Corydalidae). Details of the large mandibles are clearly observed, as well as the distinctive six ocelli and three segmented antennae. Based on the size of the head, we estimate that the complete specimen would have been at least 20 mm. Typically living under rocks in swiftly moving streams, this specimen was a formidable predator.

Though these three specimens only represent a minuscule cross section of the Cretaceous arthropods, they show that significant diversity in predators had already been attained in this evolutionary important time period.