Abstract:
BACKGROUND: A challenge within the context of cryptic species is the delimitation of individual species within the complex.
Statistical parsimony network analytics offers the opportunity to explore limits in situations where there are insufficient
species-specific morphological characters to separate taxa. The results also enable us to explore the spread in taxa that have
invaded globally.
METHODOLOGY/PRINCIPAL FINDINGS: Using a 657 bp portion of mitochondrial cytochrome oxidase 1 from 352 unique
haplotypes belonging to the Bemisia tabaci cryptic species complex, the analysis revealed 28 networks plus 7 unconnected
individual haplotypes. Of the networks, 24 corresponded to the putative species identified using the rule set devised by
Dinsdale et al. (2010). Only two species proposed in Dinsdale et al. (2010) departed substantially from the structure
suggested by the analysis. The analysis of the two invasive members of the complex, Mediterranean (MED) and Middle East
– Asia Minor 1 (MEAM1), showed that in both cases only a small number of haplotypes represent the majority that have
spread beyond the home range; one MEAM1 and three MED haplotypes account for .80% of the GenBank records. Israel is
a possible source of the globally invasive MEAM1 whereas MED has two possible sources. The first is the eastern
Mediterranean which has invaded only the USA, primarily Florida and to a lesser extent California. The second are western
Mediterranean haplotypes that have spread to the USA, Asia and South America. The structure for MED supports two home
range distributions, a Sub-Saharan range and a Mediterranean range. The MEAM1 network supports the Middle East - Asia
Minor region.
CONCLUSION/SIGNIFICANCE: The network analyses show a high level of congruence with the species identified in a previous
phylogenetic analysis. The analysis of the two globally invasive members of the complex support the view that global
invasion often involve very small portions of the available genetic diversity.