Angela McDonnell

• Doctor of Philosophy
• Professor (Assistant) at St. Cloud State University

Subtribe Gonolobinae of the cosmopolitan family Apocynaceae is diverse and represents the largest radiation of milkweeds in the New World (∼500 species). The largest genus, Matelea, is an amalgam that was united largely by a perceived lack of discrete morphological variation, particularly in floral structures. Using plastid and nuclear DNA sequence...

A new species of milkweed vine from Texas, Matelea hirtelliflora (Apocynaceae), is described and illustrated. This species is similar to congeners in the southeastern United States, but is distinguished by hirtellous corollas with shorter petals than its presumed closest relatives and by corona lobes with fleshy segments, each with two triangular p...

A new species from Sonora, Polystemma canisferum (Apocynaceae, Asclepiadoideae, Gonolobinae), is described. Polystemma is a segregate of Matelea consisting of species that possess hairs that are filled with a crystalline substance at maturity, filiform or fleshy corona appendages, and fusiform fruits. The new species shares these characters but is...

Matelea chihuahuensis is reported as an addition to the floras of New Mexico and the United States with three occurrences in close proximity documented from Hidalgo County. A full description of the species is presented, along with photos, a distribution map, and a review of its taxonomic history. A lectotype is designated. Matelea chihuahuensis is...

Matelea (Apocynaceae, Asclepiadoideae) is a genus of approximately 225 species in milkweed subtribe Gonolobinae. This New World genus is predominantly found in tropical to subtropical regions and is represented in Oklahoma by four species. Two of these, M. biflora and M. cynanchoides, are closely related, non-twining perennial herbs that have long...

Angiosperms are the cornerstone of most terrestrial ecosystems and human livelihoods1,2. A robust understanding of angiosperm evolution is required to explain their rise to ecological dominance. So far, the angiosperm tree of life has been determined primarily by means of analyses of the plastid genome3,4. Many studies have drawn on this foundation...

A new species of functionally dioecious bush tomato of Solanum subgenus Leptostemonum is described. Solanum scalarium Martine & T.M.Williams, sp. nov. , is a member of the taxonomically challenging “Kimberley dioecious clade” in Australia and differs from other species in the group in its spreading decumbent habit and conspicuously prickly male flo...

Oenothera sect. Calylophus is a North American group of 13 recognized taxa in the evening primrose family (Onagraceae) with an evolutionary history that may include independent origins of bee pollination, edaphic endemism, and permanent translocation heterozygosity. Like other groups that radiated relatively recently and rapidly, taxon boundaries w...

Premise of the study: Evolutionary studies require solid phylogenetic frameworks, but increased volumes of phylogenomic data have revealed incongruent topologies among gene trees in many organisms both between and within genomes. Some of these incongruences indicate polytomies that may remain impossible to resolve. Here we investigate the degree o...

Premise of study: 5-6% of Angiosperm species exhibit a dioecious sexual system, with unisexual "male" or "female" flowers borne on separate plants. The consequent need for inter-individual pollen exchange is a special challenge for taxa where pollen is the sole pollinator reward. Dioecious Australian Solanum assure visits from pollen-foraging bees...

In this special issue of the American Journal of Botany, together with a companion issue of Applications in Plant Sciences, we gather a set of papers that focus on a new, common phylogenomic toolkit, the Angiosperms353 probe set, and illustrate its potential for evolutionary synthesis by promoting open collaboration across our community.

Premise: Divergence depends on the strength of selection and frequency of gene flow between taxa, while reproductive isolation relies on mating barriers and geographic distance. Less is known about how these processes interact at early stages of speciation. Here, we compared population-level differentiation in floral phenotype and genetic sequence...

Premise of the study Evolutionary studies require solid phylogenetic frameworks, but increased volumes of phylogenomic data have revealed incongruent topologies among gene trees in many organisms both between and within genomes. Some of these incongruences indicate polytomies that may remain impossible to resolve. Here we investigate the degree of...

Oenothera sect. Calylophus is a North American group of 13 recognized taxa in the evening primrose family (Onagraceae) with an evolutionary history that may include independent origins of bee pollination, edaphic endemism, and permanent translocation heterozygosity. Like other groups that radiated relatively recently and rapidly, taxon boundaries w...

In Pennsylvania Baptisia australis var. australis is found along only four waterways: the Allegheny River, Youghiogheny River, Clarion River, and Red Bank Creek. Because of its limited distribution and small number of extant populations, the species is considered state-threatened in Pennsylvania. In addition, the riparian prairie habitat that Penns...

The morphologically-diverse members of Chenopodium in Hawai‘i are a set of tetraploid taxa distinguished from other members of the circumglobally distributed genus by minute morphological characters. Because of this, the geographic origin of Hawaiian Chenopodium has remained unclear. Across the Hawaiian Archipelago, Chenopodium taxa are morphologic...

Premise: Botanical faculty and staff at academic institutions are often tasked with establishing and/or caring for plant collections held in small greenhouse facilities. Once plants are in place, an especially acute challenge is managing plant pest/pathogen populations. Integrated pest management (IPM) approaches are an excellent option, but few e...

A bush tomato that has evaded classification by solanologists for decades has been identified and is described as a new species belonging to the Australian “Solanum dioicum group” of the Ord Victoria Plain biogeographic region in the monsoon tropics of the Northern Territory. Although now recognised to be andromonoecious, S. plastisexum Martine & M...

The dioecious and andromonoecious Solanum taxa (the “S. dioicum group”) of the Australian Monsoon Tropics have been the subject of phylogenetic and taxonomic study for decades, yet much of their basic biology is still unknown. This is especially true for plant-animal interactions, including the influence of fruit form and calyx morphology on seed d...

Individual gene trees for each of the seven loci as estimated by IQ-TREE. Values at nodes reflect bootstrap support. (PDF)

List of specimen vouchers and GenBank numbers for sequences used in this study. For each accession, information is as follows: collector and collector number, DNA isolate name, locality, date of collection, acronym for herbarium (in parentheses) where voucher is held, and gene regions recovered for that accession. GenBank accession numbers for gene...

The dioecious and andromonoecious Solanum taxa (previously described as the “S. dioicum group”) of the Australian Monsoon Tropics have been the subject of phylogenetic and taxonomic study for decades, yet much of their basic biology is still unknown. This is especially true for plant-animal interactions, including the influence of fruit form and ca...

Premise of the study: We provide the largest phylogenetic analyses to date of Apocynaceae in terms of taxa and molecular data as a framework for analyzing the evolution of vegetative and reproductive traits. Methods: We produced maximum-likelihood phylogenies of Apocynaceae using 21 plastid loci sampled from 1045 species (nearly 25% of the famil...

• Premise of the study: Hyb-Seq, the combination of target enrichment and genome skimming, allows simultaneous data collection for low-copy nuclear genes and high-copy genomic targets for plant systematics and evolution studies. • Methods and Results: Genome and transcriptome assemblies for milkweed (Asclepias syriaca) were used to design enrichmen...