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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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Melica as an emerging model system for comparative studies in temperate Pooideae grasses
Abstract Background and AimsPooideae grasses contain some of the world’s most important crop and forage species. Although much work has been conducted on understanding the genetic basis of trait diversification within a few annual Pooideae, comparative studies at the subfamily level are limited by a lack of perennial models outside ‘core’ Pooideae. We argue for development of the perennial non-core genus Melica as an additional model for Pooideae, and provide foundational data regarding the group’s biogeography and history of character evolution. MethodsSupplementing available ITS and ndhF sequence data, we built a preliminary Bayesian-based Melica phylogeny, and used it to understand how the genus has diversified in relation to geography, climate and trait variation surveyed from various floras. We also determine biomass accumulation under controlled conditions for Melica species collected across different latitudes and compare inflorescence development across two taxa for which whole genome data are forthcoming. Key ResultsOur phylogenetic analyses reveal three strongly supported geographically structured Melica clades that are distinct from previously hypothesized subtribes. Despite less geographical affinity between clades, the two sister ‘Ciliata’ and ‘Imperfecta’ clades segregate from the more phylogenetically distant ‘Nutans’ clade in thermal climate variables and precipitation seasonality, with the ‘Imperfecta’ clade showing the highest levels of trait variation. Growth rates across Melica are positively correlated with latitude of origin. Variation in inflorescence morphology appears to be explained largely through differences in secondary branch distance, phyllotaxy and number of spikelets per secondary branch. ConclusionsThe data presented here and in previous studies suggest that Melica possesses many of the necessary features to be developed as an additional model for Pooideae grasses, including a relatively fast generation time, perenniality, and interesting variation in physiology and morphology. The next step will be to generate a genome-based phylogeny and transformation tools for functional analyses.
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- Award ID(s):
- 2120732
- PAR ID:
- 10464653
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Annals of Botany
- ISSN:
- 0305-7364
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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