tween one habitat and the next? Having lo- 

 cated the harlequin's prime habitat, per- 

 haps we could unravel this mystery. 



As night closed in, we checked our 

 headlamps. Equipped with red filters, the 

 lights would be invisible to insect eyes 

 while providing us with a little illumina- 

 tion on this moonless night. We waited 

 silently, hoping that we would not en- 

 counter a deadly fer-de-lance coiled be- 

 neath the tree trunk (as we had on two pre- 

 vious occasions). Within moments, our 

 apprehension was forgotten as a large 

 male harlequin descended from the 

 canopy. The size of a small bird, it flew in 

 slow motion, its enormously elongated 

 forelegs outstretched and its body held 

 vertically. Minutes later, the buzzing of 

 large wings signaled the arrival of a sec- 

 ond big male. 



The scene was set for one of the most 

 remarkable displays of male combat in the 



insect world, a struggle to gain control of 

 prime egg-laying sites on the tree. In a 

 coleopteran version of jujitsu, each male 

 repeatedly reared up on his hind legs, 

 lunged forward, and using his forelegs as 

 hooked levers, tried to overturn the other 

 and toss him from the tree. Victory usually 

 goes to the male with the longest forelegs, 

 but these combatants were closely 

 matched, and all attempts at tossing failed. 

 Not the hard-wired robots insects are often 

 thought to be, the beetles abandoned their 

 standard tactics as the contest escalated, 

 and their attacks and counterattacks grew 

 more complex and less predictable. Fi- 

 nally, after a frenzied ten minutes of vi- 

 cious bites, flailing forelegs, and wildly 

 waving antennae, one contestant retreated, 

 part of his left antenna amputated by his 

 opponent's powerful mandibles. The vic- 

 tor then took up the task of guarding his 

 mating territory. Within an hour a female 



arrived, and the pair began to copulate. 



For harlequin beetles, mating is a pro- 

 tracted affair. After copulation, the male 

 guards the site as his mate chews a hole in 

 the half-inch-thick bark, an arduous task 

 that may take her an hour. Excavation 

 completed, the female injects a single egg 

 into the pit and again copulates with the 

 male. She may continue this sequence 

 through the night until she has left a tell- 

 tale line of five to ten holes in the bark. 



As the pair we watched began to copu- 

 late a second time, we crept a little closer, 

 confident that the harlequins were too pre- 

 occupied to notice. To couple with the fe- 

 male, the male arched his abdomen down- 

 ward, leaving the space beneath his wing 

 covers exposed. Straining to see in the dim 

 red light, we spotted a pseudoscorpion 

 moving down the male's abdomen. Climb- 

 ing onto the female beetle's ovipositor, it 

 paused and raised its pincers. Apparently 



38 Natural History 3/94 



