The Bemisia tabaci cryptic (sibling) species group — imperative for a taxonomic reassessment

• Published in: Current opinion in insect science Vol. 57; p. 101032
• Main Authors: Brown, Judith K, Paredes-Montero, Jorge R, Stocks, Ian C
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01-06-2023
• Subjects: Animals; Biological Evolution; Hemiptera - genetics; Humans; Phylogeny; Siblings
• ISSN: 2214-5745; 2214-5753; 2214-5745
• DOI: 10.1016/j.cois.2023.101032

The taxonomy of the Bemisia tabaci cryptic species group remains a challenge due to the lack of morphological differentiation and porous species boundaries among its members. Additionally, it is unclear whether B. tabaci consists of several species in evolutionary stasis with limited morphological change or is the result of a recent adaptive radiation characterized by great ecological diversity but little morphological divergence. Here, a historical overview of the development of the nomenclature used to classify B. tabaci is provided covering changes after synonymizing several species in 1957 until recent insights gained from whole-genome sequencing data. The article discusses the limitations of using a 3.5% mtCOI threshold and argues that a 1% nuclear divergence cutoff better reflects ecological and biogeographic species boundaries. Finally, a plan of action is outlined for naming B. tabaci species using a Latin binomial system in accordance with the International Comission on Zoological Nomenclature (ICZN) regulations.
•Whole-genome phylogenomic analyses do not support a 3.5–4.0% COI threshold for differentiation of the Bemisia tabaci cryptic species group.•A 3.5% cutoff offers a viable threshold for differentiating putative B. tabaci cryptic species subspecies.•A nuclear genome divergence of 1% best explains the phylo-biogeographical breaks between the putative cryptic B. tabaci species.•Revisiting microscopic-level adult and pupal character states and using machine learning may aid in identifying informative fine structures.•A starting point is proposed for extending and establishing Latin binomials for the B. tabaci cryptic species group.