Plakidas (1994: figs. 10–11) ascribed galls on the main stem to N. verbesinae and those among the upper branchlets to his N. incisa. Both illustrations in Plakidas (1994) show typical galls of N. verbesinae. Whether at the lower or upper stem and regardless of size, N. verbesinae galls (Figs. 5–7) are characteristically ovate with an excessive internal growth of soft tissue through which larvae appear to bore haphazardly.
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Galls are ovate swellings of the stem of Verbesina spp. that are mostly filled with a soft tissue into which the growing larvae burrow (Fig. 6). Larval tunnels become gradually reinforced and surrounded by a persistent hard white substance while the intervening material becomes increasingly soft with age and evanesces in winter (Fig. 7). Overwintering larvae form a silken lining inside the brittle cover and pupate in place. There are at least two generations per year based on the fact that galls at plant midheight have empty tunnels in late summer.

- R. J. Gagné & M. W. Palmer: (2019) Neolasioptera spp. (Diptera: Cecidomyiidae) from stem galls of Verbesina (Asteraceae) with the description of a new species^©