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Abstract The genusLiriomyzaMik (Diptera: Agromyzidae) is a diverse and globally distributed group of acalyptrate flies. Phylogenetic relationships amongLiriomyzaspecies have remained incompletely investigated and have never been fully addressed using molecular data. Here, we reconstruct the phylogeny of the genusLiriomyzausing various phylogenetic methods (maximum likelihood, Bayesian inference, and gene tree coalescence) on target‐capture‐based phylogenomic datasets (nucleotides and amino acids) obtained from anchored hybrid enrichment (AHE). We have recovered tree topologies that are nearly congruent across all data types and methods, and individual clade support is strong across all phylogenetic analyses. Moreover, defined morphological species groups and clades are well‐supported in our best estimates of the molecular phylogeny.Liriomyza violivora(Spencer) is a sister group to all remaining sampledLiriomyzaspecies, and the well‐known polyphagous vegetable pests [L. huidobrensis(Blanchard),L. langeiFrick,L. bryoniae.(Kaltenbach),L. trifolii(Burgess),L. sativaeBlanchard, andL. brassicae(Riley)]. belong to multiple clades that are not particularly closely related on the trees. Often, closely relatedLiriomyzaspecies feed on distantly related host plants. We reject the hypothesis that cophylogenetic processes betweenLiriomyzaspecies and their host plants drive diversification in this genus. Instead,Liriomyzaexhibits a widespread pattern of major host shifts across plant taxa. Our new phylogenetic estimate forLiriomyzaspecies provides considerable new information on the evolution of host‐use patterns in this genus. In addition, it provides a framework for further study of the morphology, ecology, and diversification of these important flies.
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Morphological evolution of silica scales in the freshwater genus Synura (Stramenopiles)
A high degree of morphological variability is expressed between the ornately sculptured siliceous scales formed by species in the chrysophycean genus,Synura. In this study, we aimed to uncover the general principles and trends underlying the evolution of scale morphology in this genus. We assessed the relationships among thirty extantSynuraspecies using a robust molecular analysis that included six genes, coupled with morphological characterization of the species‐specific scales. The analysis was further enriched with addition of morphological information from fossil specimens and by including the unique modern species,Synura punctulosa. We inferred the phylogenetic position of the morphologically uniqueS. punctulosa, to be an ancientSynuralineage related toS. splendidain the sectionCurtispinae. Some morphological traits, including development of a keel or a labyrinth ribbing pattern on the scale, appeared once in evolution, whereas other structures, such as a hexagonal meshwork pattern, originated independently several times over geologic time. We further uncovered numerous construction principles governing scale morphology and evolution, as follows: (i) scale roundness and pore diameter decreased during evolution; (ii) elongated scales became strengthened by a higher number of struts or ribs; (iii) as a consequence of scale biogenesis, scales with spines possessed smaller basal holes than scales with a keel and; and (iv) the keel area was proportional to scale area, indicating its potential value in strengthening the scale against breakage.
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- Award ID(s):
- 1940070
- PAR ID:
- 10453837
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Phycology
- Volume:
- 57
- Issue:
- 1
- ISSN:
- 0022-3646
- Page Range / eLocation ID:
- p. 355-369
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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