Morphometric Relationship, Phylogenetic Correlation, and Character Evolution in the Species-Rich Genus Aphis (Hemiptera: Aphididae)

Abstract

BackgroundThe species-rich genus Aphis consists of more than 500 species, many of them host-specific on a wide range of plants, yet very similar in general appearance due to convergence toward particular morphological types. Most species have been historically clustered into four main phenotypic groups (gossypii, craccivora, fabae, and spiraecola groups). To confirm the morphological hypotheses between these groups and to examine the characteristics that determine them, multivariate morphometric analyses were performed using 28 characters measured/counted from 40 species. To infer whether the morphological relationships are correlated with the genetic relationships, we compared the morphometric dataset with a phylogeny reconstructed from the combined dataset of three mtDNA and one nuclear DNA regions.Principal FindingsBased on a comparison of morphological and molecular datasets, we confirmed morphological reduction or regression in the gossypii group unlike in related groups. Most morphological characteristics of the gossypii group were less variable than for the other groups. Due to these, the gossypii group could be morphologically well separated from the craccivora, fabae, and spiraecola groups. In addition, the correlation of the rates of evolution between morphological and DNA datasets was highly significant in their diversification.ConclusionsThe morphological separation between the gossypii group and the other species-groups are congruent with their phylogenetic relationships. Analysis of trait evolution revealed that the morphological traits found to be significant based on the morphometric analyses were confidently correlated with the phylogeny. The dominant patterns of trait evolution resulting in increased rates of short branches and temporally later evolution are likely suitable for the modality of Aphis speciation because they have adapted species-specifically, rapidly, and more recently on many different host plants.

Molecular and morphological differentiation between Aphis gossypii Glover (Hemiptera, Aphididae) and related species, with particular reference to the North American Midwest

“…The analysis of different species included in this study largely corroborates the results obtained by Coeur d’acier et al (2007), Kim and Lee (2008), Kim et al (2010a), Kim et al (2010b), Kim et al (2011) and Lagos et al (2014b). The gossypii complex in the North American Midwest contains the following native species, Aphid oestlundi and Aphid monardae , and the invasive species Aphid gossypii and Aphid sedi .…”

Morphological vs. molecular delineation of taxa across montane regions in Europe: the case study ofGammarus balcanicusSchäferna, (Crustacea: Amphipoda)

“…Omland ; Kim et al. ; Seligmann ). However, in our case, the high morphological diversity within sites is contrasting with low molecular distances.…”

Aphis (Hemiptera: Aphididae) species groups found in the Midwestern United States and their contribution to the phylogenetic knowledge of the genus

“…R. maidis belongs to the tribe Aphidini that is divided into 2 subtribes: Rhopalosiphina, to which Rhopalosiphum and Hyalopterus belong, and Aphidina to which the genus Aphis belongs (Remaudière & Remaudière, 1997). The 2 subtribes are separated morphologically by the position of the marginal tubercles on abdominal segments I and VII in relation to a line formed by the spiracular openings (Stroyan, 1984;Heie, 1986;Kim & Lee, 2008;Kim et al, 2010). The phylogenetic trees obtained using EF1-α sequences (Fig.…”