The Nearctic members of the Dioryctria schuetzeella group (D. reniculelloides and D. pseudotsugella) (Pyralidae: Phycitinae) are notoriously difficult to identify, due to intermediate morphological forms and a broadly sympatric distribution. Given these difficulties, we tested the traditional delimitation of D. reniculelloides and D. pseudotsugella using a combination of molecular, morphological, and ecological characters. Restricted gene flow was found between an eastern D. reniculelloides clade and a western D. pseudotsugella clade, which were also supported by morphological variation and larval host plant association. Diagnosis of these two species remains difficult due to overlapping variation and future examinations are needed to elucidate which barriers to gene flow are maintaining this sympatric distribution.