Asterobemisia, Trehan, 1940

Gill, Raymond, 2012, A preliminary report on the World species of Bemisia Quaintance and Baker and its congeners (Hemiptera: Aleyrodidae) with a comparative analysis of morphological variation and its role in the recognition of species Raymond Gill, Insecta Mundi 2012 (219), pp. 1-99 : 15-16

Asterobemisia and Neobemisia . Like the tabaci complex, there may be many cryptic species that are geographically isolated, or there may be fewer named species than there actually are. Unlike the tabaci complex, however, adults in the afer complex in some cases have morphological characteristics in the compound eye that suggest that more as yet unrecognized species may be involved as appears to be the case in B. tabaci . So far, there does not seem to be variability in the number of ommatidia that connect the upper and lower compound eyes in adults from the same population, although this needs to be studied further. Since the puparial morphology is so variable and seems to occur often in similar patterns in populations across the globe ommatidial number may therefore delimit some species.

Conclusion

The number of synonyms of Bemisia tabaci is due partly to the extreme plasticity of the puparial stages. Even though the mechanisms for the puparial variability are now largely understood, as are the limits of this variability within some generic groupings, we still cannot arrange this variability into well-limited species and genera. Early work by Mound (1963) and Russell (1957) showed that whitefly puparial morphology in the genera Bemisia and Trialeurodes Cockerell can be altered by environmental factors. Further studies have shown variable pupal morphology to be common in many other genera in the subfamily Aleyrodinae . Current molecular studies are beginning to shed some light on a few morphological structures that could be reliable generic and specific characters for some of the Bemisia species and related genera, by giving us a glimpse of evolutionary relationships that have not been visible to the classical taxonomist previously. Hopefully research will give us some indication of which morphological characters are useful in this way, and those characters that are not of importance. While there are no good morphological characters for separating the various races of B. tabaci (as currently understood), there are some interesting differences in biology, mating behavior,

cross fertility and virus transmission that suggest that there are cryptic species involved, and molecular data are emerging suggestive of that possibility. Recent molecular work has provided insights into the relationships of many of the variants (biotypes, strains, races, haplotypes) of the tabaci complex.

Several of the species that are close to B. tabaci morphologically include B. capitata , B. formosana and B. graminus , and are now included in a tabaci complex of species. However, the relationships of species in other genera that may in fact belong in the genus Bemisia , and may even be part of the tabaci complex, (e.g. Bemisiella , Lipaleyrodes , Pealius azaleae and Parabemisia myricae ), are still unclear. In addition, the status of some species apparently related to B. afer are also open for question, such as whether species of Asterobemisia and Neobemisia belong in the afer complex, or are possibly a single highly variable species. Based on these studies it is possible that the afer complex of species,

including B. tuberculata in South America, B. berbericola in North America, B. leakii and A. moringae in India, may all be the same species that has been spread by humans, or more likely a collection of cryptic species like B. tabaci as has been suggested by the recent molecular work of Dinsdale et al

(2010).