Adults are approximately 6 mm long. In general, the distribution of each species of beetle follows the distribution of its primary host. The life cycles of the beetles are similar with some variation in timing and effect. Also, while the mode of action in killing individual trees is the same for all three species, affected trees vary in their display of symptoms. It is necessary to know the differences when identifying the causal agent, establishing where the infestation is in its cycle, and for selecting the most appropriate treatment prescription.
Romance begins at arm's length for two harlequin beetles.
They gingerly check each other out with their oversize limbs in a courtship ritual. Life cycles All three beetle species have similar life cycles, progressing from egg, through four larval instars, to pupa, and finally to adult. The timing of various components of the life cycles are summarized in Table 2. The timing of life cycle events for any species of bark beetle will vary from year to year and from location to location due to variations in climate and local weather. 2.Males join the females and each pair construct an egg gallery under the bark, parallel to the grain.