The jump of the click beetle (Coleoptera: Elateridae)—energetics and mechanics

Abstract

Some aspects of the energetics and mechanics of two jumps made by a single specimen of Athous haemorrhoidalis (Fab.) are considered. In the first jump, the 40 mg beetle had a take‐off velocity of 2–4 m/s and the jumping action occurred in about 064 ms; in the second jump, the take/off velocity was 2–26 m/s and the jumping action took about 0–53 ms. Energy budgets have been constructed in two different ways for each jump, and the total energy involved in each case was estimated to lie between 1–6 × 10−4 J and 3–8 × 10−4 J. Power output during the jumping action (a “catapult”) lay between 80 × 103 W/kg muscle and 180 × 103 W/kg muscle, whilst power output during the energy storing pre‐jump period (of about 0–4 s) was at least 130 W/kg muscle (at over 25°C). Forces and tensile stresses in the jumping muscles and their apodemes have also been calculated. The method of jumping appears to be fairly inefficient in that only about 50–60% of the energy expended in the jumping action is energy of translation, which actually raises the beetle.

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

“…The direct elytral muscles pretending to be closers are so feeble in histerids that M36 and M35 were omitted by me (Frantsevich, 1981), M35 [labeling by Larsén, (Larsén 1966)] was not identified by Beutel and Komarek and announced as probably absent, while their description of M36 corresponds not to M36 but to M35 (Beutel and Komarek, 2004). It is clear that such fast movement needs previous storage of energy, presumably in the isometrically contracting large elevators of the prothorax, and its momentary release after unlocking, the mechanism resembling the jump of a click beetle (Evans, 1973).…”

“…M4 was defined as the depressor in an elaterid Athous haemorrhoidalis (Evans, 1973). The difference between Athous and Melolontha with respect to the drive of this muscle is in the shape of the prophragma (straight in Melolontha, curved down in Athous) and in the type of the joint between the pro-and mesothorax.…”

Jumping performance of planthoppers (Hemiptera, Issidae)

“…For example, the larvae of the fruit fly Ceratitis capitata when ready to pupate jump to avoid predators by anchoring mouth hooks at the rear of the body to roll up the body and then unfurling it rapidly by elastic recoil (Maitland, 1992). Springtails rapidly extend an abdominal appendage (Brackenbury and Hunt, 1993;Christian, 1978) and click beetles jack-knife their body at the junction between the pro-and mesothorax (Evans, 1972;Evans, 1973;Kaschek, 1984). The ant Gigantiops destructor jumps by rapidly extending both the middle and hind pairs of legs while moving part of the abdomen forwards and holding it there during a jump (Baroni et al, 1994;Tautz et al, 1994).…”

Jumping in a wingless stick insect,Timema chumash(Phasmatodea,Timematodea, Timematidae)

“…Springtails (Collembola) jump by rapidly extending their terminal abdominal appendages (Brackenbury and Hunt, 1993) whereas some ants (Baroni et al, 1994;Tautz et al, 1994), a stick insect (Phasmida) (Burrows and Morris, 2002) and Petrobius (Thysanura) (Evans, 1975) use movements of the whole abdomen. By contrast, click beetles (Coleoptera) move the prothorax against the mesothorax (Evans, 1972;Evans, 1973) and the trapjaw ant (Hymenoptera) rapidly closes its mandibles against the ground or an approaching object to propel itself upwards or backwards (Patek et al, 2006).…”