a. Oesophageal opening, pecten epipharyngis and premandible; b. Ventromentum - note the crenulate anterior margin;
c. Mentum - note 4th laterals slightly reduced (type I-II), and c2 teeth separate from broad squarish c1 (type III);
d. Mandible - note 3rd inner tooth is distinct but not dark; e Antenna - with relatively long basal segment.
Fig. a courtesy of I. Proulx.