Scanning EM projects of the Hemiptera Section
Scanning EM studies of uncoated insects
(K. Schönitzer, J. Schuberth, E. Diller, R. Melzer & L.-Y. Liu)
Sometimes the specimens can not be sputtered because they are unique spcimens such as types. In these cases it is possible to make SEM picture of unsputtered material using very low high tension such as 1,5 kV. Furthermored it is important to work rather fast to reduce the accumulation of charging effects.
Kopf (links) und Propodeum (rechts) von Hintelmannia elisabethae.
Frequently it is useful to investigate insects which are pinned on a needle. In such cases the needle may be fixed with a plastic conductive carbon cement (`Leit-C-Plast@) on the stubs. the object should be positions in such a way that the part which is to be investigated is directed thoroughly upwards. It may be necessary to shorten the needle. In such cases the insect must be mounted on another needle afterwards. The position of the object may be changed for subsequent pictures.
Dirophanes coryphaeus, female, head and mandibles (Image: E. Hower)
In cooperation with a colleague in Taiwan an investigation on the structures of Bostrichidae (powder-post beetles) with ESEM was undertaken and its use for taxonomy was demonstrated: