MEROPE TUBER (MECOPTERA) : 
A WING-BODY INTERLOCKING MECHANISM 
By T. F. Hlavac 1 
Museum of Comparative Zoology 
Harvard University 
Cambridge, Massachusetts 02138 
As an insect pushes its dorsal surface against obstacles while 
moving through a substrate, the wings will tend to be forced apart. 
In many Coleoptera, such divergence is prevented by a complex 
of devices interlocking the elytra with the thorax and abdomen. A 
common interlocking mechanism involves intermeshing of parallel 
arrays of setae angled towards the potentially disrupting force 
(Fig. 2). A similar high friction binding system on the mesojugum 
and metascutellum of Merope tuber provides additional evidence for 
the ground dwelling habits of this rare mecopteran. 
The fore-jugal lobe of Merope is highly modified relative to its 
counterpart on the hind wing and as compared with the jugal regions 
of other panorpoids (Fig. 1 ; JL2, JL3). It does not bear setae and 
does not appear to function in wing coupling. More importantly, the 
mesojugal lobe is much thicker, more heavily sclerotized than the wing 
proper, is quite rigid, yet capable of slight movement about the third 
anal vein, but does not fold over as the wing comes to rest. The 
ventral surface is completely covered with uniformly small (.007 
X .003 mm) flat topped carinae, angled posteriorly and organized 
in rows perpendicular to the long axis of the wing (Figs. 1, JL2; 
3, 4). The metascutellum bears two patches of anteriorly projecting 
ridges about twice as long (.017 X .003 mm) but about as high as 
those on the fore wing (Figs. 1, R, S3; 5). 
In rest position, the jugal lobes lie close together and directly above 
the striate metathoracic areas. When so placed, a small ventral 
movement will cause the slanting nearly parallel ridges to intermesh. 
Two functions, which may be combined, may be served by the jux- 
taposition of parallel carinae: stridulation and interlocking. Stridu- 
lation is an unlikely function for these structures. As the wing 
moves medially to rest, the ridges move parallel to one another, not 
Research supported by NSF grant GB 31173, F. M. Carpenter, Harvard 
University, Principal Investigator. Manuscript completed at Cornell where 
E. H. Smith kindly made necessary facilities available. 
Manuscript received by the editor June 15, 1974. 
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