Liriomyza huidobrensis may be composed of two cryptic species
Observations of differences between populations of Liriomyza huidobrensis (EPPO A2 quarantine pest) concerning crop preferences and levels of insecticide resistance in the field have led to the assumption that L. huidobrensis might consist of 2 or more cryptic species. Phylogenetic relationships among populations of L. huidobrensis from different origins (Ecuador, Guatemala, Indonesia (Java), Israel, Sri Lanka, US (California, Hawaii) were studied by comparing DNA sequences (mitochondrial cytochrome oxidase genes). Results showed that the currently recognized L. huidobrensis contains two very distinct groups: one clade composed of specimens from California and Hawaii, and another clade composed of specimens from South and Central America and also from other parts of the world where L. huidobrensis has recently been introduced (Indonesia, Israel, Sri Lanka). These results are consistent with field observations of differences in pest status and insecticide resistance between L. huidobrensis populations (California and Hawaii populations showed a different behaviour from populations in other parts of the world). The author noted that these results suggest that the populations recently introduced into Indonesia, Israel, Sri Lanka originate from South or Central America. However, it is premature to conclude that all recently introduced populations came from this region. It is also pointed out that so far, there are no known morphological differences that could distinguish between the 2 L. huidobrensis clades. For the moment, it was felt too early to propose any change in the taxonomy of L. huidobrensis, but further studies on morphological characteristics and additional DNA sequences will be conducted.
Sources
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Scheffer, S.J. (2000) Molecular evidence of cryptic species within the Liriomyza huidobrensis (Diptera: Agromyzidae).
Journal of Economic Entomology, 93(4), 1146-1151.
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