Comparing the efficacy of morphological characteristics in the identification of Monochamus titillator and M. carolinensis (Coleoptera: Cerambycidae)

Pine sawyers, such as Monochamus titillator and M. carolinensis, are involved in multi-trophic interactions with woodwasps, bark beetles, buprestids, and other arthropods.  Their geographic ranges and appearance are virtually identical; however, most research has focused only on a single species.  Characteristics used to distinguish the two species are the curvature and shape of the point at the elytral apex.  However, these characters occur along a gradient and elytra can be easily broken.  Preliminary research shows these species will not interbreed, and the lack of defined identification could lead to misinterpreted data.  Monochamus adults were captured using both Lindgren funnel and panel traps beginning in mid-April and continuing through mid-December.  Traps were placed in Arkansas, Texas, and Louisiana and collected on a regular basis.  Species were identified using the current physical characteristics suggested.  Body length, pronotal width, and weight of adults were measured.  There are significant differences between species among all three measurements.  This suggests that size may be as effective, if not more so, than the morphological characters currently used in identification.  Future research includes molecular diagnostics to confirm or reject the initial identification.  This will solidify my assumptions that simple measurements are accurate identifiers of species.