The morphology of the general structure of the most common Egyptian elaterid species, Lanelater notodonta (Latreille) was given and illustrated for the first time to clarify the main diagnostic characters used in the identification and classification of family Elateridae. The head is prognathous. The Y- shaped epicarnial suture is absent. Labrum is semicircular transverse and convex. Mandibles are flattened, sclerotized with two sharp teeth. Maxilla consists of cardo, basistipes, mediostipes, lacinia, galea and 4-segmented maxillary palp; the terminal one is securiform in shape. Galea and lacinia are brush-like. Labium has 3-segmented labial palp with the terminal segment securiform. Antennae serrate 11-segmented. Prothorax articulates freely with mesothorax and has sharp and divergent posterior angles. Anterior edge of prosternum broadly rounded and distinct, the chin piece covers the ventral mouthparts. Prosternum has sterno-pleural suture into which the antennae lies at rest. prosternum has backwardly directed narrow process, prosternal intercoxal process. Mesosternum has a mesosternal cavity into which prosternal intercoxal process enters to aid in clicking. The elytron contains veins and no cross veins. Hind wing membranous. The veins are costa, subcosta, radius which branches into R1 and radial recurrent while its base is fading, the media only represent a recurrent vein, which is fading at the base and fused with the distal part of cubitus before reaching the anal margin forming (M+Cu) and fourth anal vein. The apical part of the wing bears two distinct sclerotized areas lying beyond and detached from the main veins. The wedge cell is absent in the hind wing and tibia provided with two spurs. Tarsal formula is 5-5-5. Abdomen consists of eight terga in both male and female, only five sterna are visible ventrally. There are eight pleura and seven pairs of spiracles. The first pair arcuate and is larger than the rest of spiracles. Male genitalia consist of median lobe and tegmen composed of basal piece and parameres and ejaculatory duct. Female genitalia consist of stylus, small coxite divided ventrally and pointed at the place of articulation with the valvifer. The valvifer is a long baculum. L. notodonta shows sexual dimorphism which is based completely on the shape of the eighth abdominal sternite. In male the eighth abdominal sternum is strongly notched or truncate at the distal margin, while in female this segment has pointed distal margin with spiculum gastral very long. The males are smaller in size than females.
Key words: Morphology, Lanelater notodonta