Antennae of first instar larvae comprised a smooth four-segmented basiflagellum and a seven-segmented, sensilla-rich distiflagellum. Lengthening of the basiflagellum was achieved by the addition of two annuli per moult, generated by division of the basal annulus (meriston).
Source: wiktionary
Morphologically, the antennae (Figs. 2, 3) (the average length, n = 4 for both species) in L. occidentalis are shorter (12.22 mm) in comparison to L. zonatus (15.67 mm). In L. occidentalis (Fig. 3a,c,e,g), the length of the particular segments is approximately: scape (2.61 mm), pedicel (3.86 mm), basiflagellum (2.60 mm), distiflagellum (3.14 mm).
Source: wiktionary