1983] 
Johnson — Claeoderes hivinaia 
137 
sawdust and other debris adhere. As she rocks in, the material 
appears to be added to the hole. 
A female may drill and oviposit three times in succession (Fig. 1). 
Female Aggression 
Aggression is instigated by females before they drill and by 
females that have just completed oviposition. The aggression is usu- 
ally directed against drilling females. The encounter may involve 
only an intention movement, or the instigator may push, poke, or 
swat a drilling female with her snout, or pry her out of her hole by 
sticking the snout under her abdomen and lifting. A fleeing female 
may be pursued several cm. Reciprocated aggression may result in a 
fight lasting 6 min or more in which the combatants kick, face one 
another and swivel their heads and forebodies, or thrust the snout 
under the other and lift suddenly; females of the same length may 
also stack themselves head-to-tail and sweep their snouts over the 
tip of their opponent’s abdomen. Fights end when a female leaves 
or is flipped from the tree. 
Guarding 
A guarding male stays with a female as she antennates the trunk, 
drills, or oviposits, keeping his rostrum or his body over her (Fig. 2). 
He responds aggressively if a rival male draws near, and he may also 
threaten a female if she approaches his female too closely, by facing 
her, advancing on her, or chasing her with a yawing movement of 
the head. 
Mating 
A male mates with the female he is guarding one to several times 
during drilling, and is especially likely to do so Just before the female 
pulls her beak out of the wood to oviposit (the onset of oviposition 
occurs less than a minute after the termination of copulation in 
about 80% of the cases (see Fig. 1)). A few seconds before mating a 
male accelerates his movements, antennates the female, and then 
mounts, sometimes trying the female’s head. Copulation lasts about 
a minute. 
Rejection 
A female not ready to drill or oviposit will walk away from males 
that approach. A drilling female can thwart mating attempts by 
walking her hind end in a circle around the pivot point of her snout 
in wood, or by withdrawing her snout entirely and walking away. 
