Description of all larval instars of Agabetes acuductus (Harris) is presented including a detailed chaetotaxic and porotaxic analysis of the cephalic capsule, head appendages, legs, last abdominal segment and urogomphi. A parsimony analysis based on the 43 informative larval characteristics was conducted with PAUP. Boostrap values indicate strong support for the monophyly of the clade containing the genus Agabetes Crotch and members of the subfamily Laccophilinae. This is supported by five synapomorphies: (i) egg bursters positioned posteriorly, contiguous to the coronal suture, (ii) presence of two lamellae clypeales in instar I, (iii) absence of the primary setae LA10 and LA12, (iv) absence of a ventroapical spinula on antennomere 3, and (v) abdominal venter 6 sclerotized.