Two Distinct Genotypes of Spissistilus festinus (Say, 1830) (Hemiptera, Membracidae) in the United States Revealed by Phylogenetic and Morphological Analyses

• Published in: Insects (Basel, Switzerland) Switzerland), 2020-01, Vol.11 (2), p.80
• Main Authors: Cieniewicz, Elizabeth, Poplaski, Victoria, Brunelli, Melina, Dombroskie, Jason, Fuchs, Marc
• Format: Article
• Language: English
• Subjects: Arizona; Bayesian theory; California; crops; cytochrome-c oxidase; Fabaceae; genes; genetic barcoding; genetic distance; genetic variation; genotype; Grapevine red blotch virus; its2; mt-coi; pests; phenotype; phylogeny; polymerase chain reaction; Southeastern United States; Spissistilus festinus; statistical analysis; topology
• ISSN: 2075-4450; 2075-4450
• DOI: 10.3390/insects11020080

(Say, 1830) (Hemiptera: Membracidae) is a frequent pest of leguminous crops in the Southern United States, and a vector of grapevine red blotch virus. There is currently no information on the genetic diversity of . In this study, populations of were collected in 2015-2017 from various crops and geographic locations in the United States, and fragments of the mitochondrial cytochrome C oxidase 1 (mt-COI) gene and the nuclear internal transcribed spacer 2 (ITS2) region were characterized by polymerase chain reaction and sequencing. Maximum-likelihood and Bayesian analyses of the mt-COI and ITS2 sequences yielded similar phylogenetic tree topologies, revealing two distinct genetic lineages with all of the specimens from California comprising one phylogenetic clade, alongside a single GenBank entry from Arizona, and all specimens from the Southeastern United States comprising a statistically-supported distinct clade, regardless of host and year of collection. The mt-COI gene fragment showed up to 10.8% genetic distance between the two phylogenetic clades. These results suggest the existence of two genotypes within in the United States. The only distinct morphological trait between the two genotypes was a less elevated pronotum in the representative specimens from California, compared to the representative specimens from the Southeastern United States. Since this phenotypic feature is inconspicuous, a diagnostic polymerase chain reaction targeting a variable region of the mt-COI fragment was developed to reliably distinguish between the specimens of the two genotypes of and to facilitate their specific identification.