Comparing morphology of Myzus persicae regarding the taxonomic clarification of a subspecies colonising tobacco

So far, multivariate analysis has been the go-to method for differentiation between the subspecies Myzus persicae persicae and M. persicae nicotianae. The present study used scanning electron microscopy (SEM) to analyse reared and field-collected individuals of both subspecies. Several characteristics led to subspecies differentiation at the morphometrical and micromorphological levels. The results are compared with earlier studies. Thus, previous differentiation by length was confirmed, which showed that M. persicae nicotianae has a relatively longer processus terminalis and siphunculus. In general, the apterae of M. p. nicotianae are larger, and both adult morphs exhibit longer hind legs than M. p. persicae. Comparing the alatae of M. p. persicae and M. p. nicotianae, only the latter possesses a scabrous cuticle covering the entire dorsal head. In contrast, alatae M. p. persicae exhibit a distal swelling of the siphunculi with a medial constriction. However, adult morphs of M. p. nicotianae bear siphunculi with constriction just beneath the flange. The SEM micromorphological analysis synergistically adds to the commonly used multivariate morphometry. Thus, closely related subspecies can be differentiated at a more detailed morphological level.

Automated summary

The present study used scanning electron microscopy (SEM) to analyze the differentiation between the subspecies Myzus persicae persicae and M. persicae nicotianae at a morphological level. The results showed that several characteristics, including body size and leg length, can be used to distinguish between the two subspecies. Furthermore, the study compared the morphological differences between the winged forms of the subspecies, revealing distinct features such as cuticle covering and swelling of the siphunculi. The SEM micromorphological analysis provides additional insights to the commonly used multivariate morphometry for subspecies differentiation.