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< Leonid I. Frantsevich >


Leonid Frantsevich

Indirect closing of the elytra in a cockchafer, Melolontha hippocastani F. (Coleoptera: Scarabaeidae).

The Journal of Experimental Biology, 2010, 213, 1836-1843.

Actuation of the closing of the elytra was previously ascribed to intrinsic muscles in the mesothorax. We investigated closing (1) by loading or arrest of some thoracic segments in a tethered flying beetle, (2) by animation, i.e. passive motion of preparations of the thorax simulating the action of some muscle, and (3) by excision of some parts of sclerites or cuts across certain muscles. We found out that depression of the prothorax, necessary to unlock the elytra, precedes their opening but elevation of the prothorax is synchronous with the closing. The closing is retarded if the elevation is retarded by loading; if the elevating prothorax is clamped, then the closing is also arrested or hindered; animation of the elevation of the prothorax in the dead animal is enough for the closing of the previously spread elytra; the closing is prevented if a piece at the hind edge of the pronotum, positioned in front of the root of an elytron, is excised. This excision also prevents closing in the in vivo experiments. Mechanical interaction between the elytron and the prothorax is limited to the contact point between the posterior edge of the pronotum and the lateral apophysis of the root. Thus, the elevation of the prothorax is the indirect and main mechanism of the closing in Melolontha.


Videos (in AVI format)

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Arrest of the prothorax with elytra amidst the flight. Approach of the pronotum toward the mesotergite during the closing.
Coordination between body parts during the normal flight. Animation of the closing of the elytra by elevation of the prothorax in a dead beetle.
Animation of the closing by pricking toward the root of the elytron in a preparation of the pterothorax. Animation of the closing fails after the excision of the left counterroot piece of the pronotum in a dead beetle.
Inability to close the right elytron after the excision of the right counterroot piece of the pronotum in vivo. Closing in a loaded beetle tethered upright.
Closing in a loaded beetle
tethered upside down.

 

Collection of films:

Courtship dances in a fly, Lispe spp.


Stick friction in a lantern fly, Lycorma delicatula


Arolium of a hornet, Vespa crabro


Indirect closing of elytra in a cockchafer, Melolontha


Righting kinematics in beetles (Insecta: Coleoptera)


Leg coordination during turning on an extremely narrow substrate in a bug, Mesocerus marginatus (Heteroptera, Coreidae)


Swimming in the Diving Wasp Prestwichia aquatica (Hymenoptera: Trichogrammatidae)


Kinematics of elytra in beetles


Indirect closing of elytra in various beetles


Double rotation of the opening (closing) elytra in beetles (Coleoptera)


Actuation and performance of the elytron-to-body articulation in a diving beetle

     

I. I. Schmalhausen Institute of Zoology, 2004-2009