Will the Real Bemisia tabaci Please Stand Up?

Abstract

Since Panayiotis Gennadius first identified the whitefly, Aleyrodes tabaci in 1889, there have been numerous revisions of the taxonomy of what has since become one of the world's most damaging insect pests. Most of the taxonomic revisions have been based on synonymising different species under the name Bemisia tabaci. It is now considered that there is sufficient biological, behavioural and molecular genetic data to support its being a cryptic species complex composed of at least 34 morphologically indistinguishable species. The first step in revising the taxonomy of this complex involves matching the A. tabaci collected in 1889 to one of the members of the species complex using molecular genetic data. To do this we extracted and then amplified a 496 bp fragment from the 3′ end of the mitochondrial DNA cytochrome oxidase one (mtCOI) gene belonging to a single whitefly taken from Gennadius' original 1889 collection. The sequence identity of this 123 year-old specimen enabled unambiguous assignment to a single haplotype known from 13 Mediterranean locations across Greece and Tunisia. This enabled us to unambiguously assign the Gennadius A. tabaci to the member of the B. tabaci cryptic species complex known as Mediterranean or as it is commonly, but erroneously referred to, as the ‘Q-biotype’. Mediterranean is therefore the real B. tabaci. This study demonstrates the importance of matching museum syntypes with known species to assist in the delimitation of cryptic species based on the organism's biology and molecular genetic data. This study is the first step towards the reclassification of B. tabaci which is central to an improved understanding how best to manage this globally important agricultural and horticultural insect pest complex.

The characteristics and expression profiles of the mitochondrial genome for the Mediterranean species of the Bemisia tabaci complex

“…Since that pivotal work in 2007, B. tabaci has been shown to be a species complex with at least 31 distinct genetic groups identified based on mtCOI [7,8,10-12]. What is more, by matching museum syntypes from the 1889 original specimen from Gennadius using mtCOI molecular maker, MED were recognized as the type species of the B. tabaci complex [13] . With the taxonomy of the B. tabaci species complex becoming clearer, it is now possible to use this information to carry out detailed comparative studies.…”

Novel molecular approach to define pest species status and tritrophic interactions from historical Bemisia specimens

“…tabaci Asia II-7 may be seen as the next stage of solving Bemisia whitefly nomenclatural confusion, since the identification of the true B . tabaci 6 . We further provided an example of cryptic species misidentification in the 1942 Japanese Bemisia species, and highlighted the on-going challenges in understanding the genetic diversity and species status of this global agricultural pest species complex.…”

Demographic Trends in Mixed <I>Bemisia tabaci</I> (Hemiptera: Aleyrodidae) Cryptic Species Populations in Commercial Poinsettia Under Biological Control- and Insecticide-Based Management

“…It is now widely recognized that B. tabaci is a cryptic species complex consisting of at least 24 morphologically indistinguishable yet behaviorally and physiologically distinct species (Boykin et al 2007, Dinsdale et al 2010, De Barro et al 2011, Liu et al 2012, McKenzie et al 2012, Tay et al 2012). To account for this variation, a convention of assigning a unique "biotype" designation to distinct B. tabaci populations was adopted, of which 36 biotypes are reported in the literature (De Barro et al 2011).…”

“…To account for this variation, a convention of assigning a unique "biotype" designation to distinct B. tabaci populations was adopted, of which 36 biotypes are reported in the literature (De Barro et al 2011). However, for various reasons, including the taxonomic appropriateness of the term "biotype," the biotype naming convention for B. tabaci has fallen out of favor (Tay et al 2012) and has been replaced by a classiÞcation system that represents the presumed phylogeographic origins of the proposed cryptic species (Dinsdale et al 2010). This classiÞcation system is based on a partial cytochrome c oxidase subunit I (COI) sequence derived from the 3Ј region of the gene.…”