ABSTRACT. Air quality is an important concern of public health that needs to be constantly monitored, especially in urban environments where half of the global population currently live. Since lichen communities from different urban areas across the world were shown to respond to air pollution with changes in species composition and functional traits, this association has long proven to be a really effective biomonitor. Our work is focused on understanding changes shown by lichen communities to monitor present and past air quality conditions across Minnesota. The final aim is to use this information to bring biomonitoring closer to the public by developing lichen-based air-quality indices and train citizen naturalists to be able to use them. With that in mind, we are using a combination of transplants of Flavoparmelia caperata (to assess air quality over a few months), lichen surveys (to understand patterns of air quality in recent years) and archival specimens (to assess heavy metal pollution over the past century). So far, lichen transplants were deployed in 10 sites across Minneapolis and Saint Paul and in a control area. For those transplants, ecophysiological measurements, such as CO₂ exchange, chlorophyll fluorescence and carbon/nitrogen contents were measured, besides heavy metal content, both prior and after exposure (six months). Photobiont turnover was also assessed using ITS barcoding. Lichen communities are currently being sampled in six urban areas across Minnesota (six sites in each city - three within urban and three within suburban matrix) using a quadrat method around the tree trunks. To track past air quality, we will use a few archival specimens (from backlog) of common and widespread species from the Bell Museum and resample those species in the same location in the present day. Preliminary results showed changes in heavy metal contents and in the physiological parameters of the exposed Flavoparmelia caperata, as well as the turnover of some clades of its main forming alga (Trebouxia) when comparing urban and suburban sites, and changes on lichen communities. Our next steps are to expand the transplants across the State, finish the lichen community sampling and, based on the combination of results, develop the air quality index and start testing it with local communities.

ABSTRACT. In general, local distribution is related to dispersal history, population dynamics, disturbance, and microclimate. Measuring plastic environmental responses is one way to assess microclimate effects on local distribution. Conocephalum is a nearly ubiquitous thalloid liverwort of shaded streams throughout North America. Local distribution may be clumped, suggesting some microhabitats are more favorable than others. In our initial study area (Clay Hill Memorial Forest (CHMF), Kentucky), Conocephalum occupied <10% of apparent habitat, leading to the hypothesis that unoccupied areas differ in moisture and light relative to occupied areas. We collected Conocephalum plants from CHMF (n = 16) and nearby Tebb’s Bend Battlefield Park (n = 6) for a greenhouse experiment. We split each plant into 4 clones, placing each in one of four factorial treatment combinations: (low or high light) x (dry or wet). We fitted pots with light-filtering shades and randomized them on a greenhouse table. Pots either contacted a capillary watering mat (wet) or were allowed to dry before hand-watering. After a 132-day period, we assessed growth rate, thallus width and depth, photosynthetic layer depth/total depth, distance between branch points, and air chamber and pore size. At high light, we expected increased photosynthetic layer and thallus depth and decreased branch point distance compared to low light. In drier conditions, we expected reduced air chamber and pore size. We found reduced water but not high light decreased branch point distance. Only under reduced water did relative photosynthetic layer depth increase with light. Thus, all plastic responses linked to water availability. Other variables were similar across treatments. We speculate that lack of air chamber and pore size plasticity limits acclimation to periodic drought. Reduced branch point distance could reflect reduced thallus expansion similar to drought constraints on vascular plant leaf expansion. This may create a closely-knit clonal patch for water conservation.

ABSTRACT. A species’ ecological role and distribution is driven by its functional traits. While vascular plant functional traits have been relatively well studied, we know far less about non-vascular plant traits. Bryophytes, one group of non-vascular, poikilohydric plants, present a nuanced response to changes in water availability and present a unique opportunity to understand the relationship between traits and environmental properties on a microclimate level. Water holding capacity (WHC) is a key functional trait that influences ecosystem hydrology. In this study we investigated variation in WHC among species, at different elevations, and at different organizational levels (individual shoots vs. intact moss mats). We expected to find that high elevation populations have higher WHC than low elevation populations of the same species. Bryophyte mats, defined as an intact unit of moss tissues spanning new growth to fully senesced along with attached duff and humus has been understood as a functional unit. Traditionally, studies on WHC have focused on individual shoots and thus have potentially missed the emergent properties of the intact mat. We expected to find that mats will be better indicators of overall WHC of a given species. Our study focused on four species found across an elevational gradient at HJ Andrews experimental forest: Rhytidioposis robusta, Kindbergia oregana, Hylocomium splendens and Rhytidiadelphus triquetrus. Samples of each species were gathered from three sites representing high and low elevation populations of each species where possible. Specimens were exposed to a rehydration and desiccation experiment. Oven dry weights and weights taken intermittently during the drying process were used to calculate WHC. Ectohydric versus endohydric WHC was evaluated using centrifugation and humidity treatments. Using an ANOVA, mean WHC capacity differed among species (p<0.01) and between shoots and mats (p<0.01), but not between elevations (p=0.9). We found a significant difference (p<0.0) in mean WHC based on species by organizational level. Bryophyte species carpet almost every exposed surface in the Western Cascade Mountains. Our research showed significant variation in WHC capacity among species and organizational levels. Illumination of these differences is crucial to understanding how bryophyte communities transform the hydrology of ecosystems. The increasing frequency and severity of forest fires suggests that understanding bryophyte contributions to forest hydrology is more pertinent than ever.

ABSTRACT. The ability of a plant to cope with abiotic stress plays an important role in its survival and reproduction. Accelerated global warming has become a major abiotic stress and can negatively impact the stability of plant population dynamics and agricultural productivity. The capacity of plants to endure heat stress varies among and within species. Within a species, individual responses to heat stress can vary due to selective pressures influenced by their specific environmental conditions. However, intraspecific variation in heat tolerance is seldom studied, especially in association with other environmental factors like light. Such studies can be used to improve crop thermotolerance through the elucidation of molecular mechanisms, as well as contribute to both in-situ and ex-situ species conservation efforts. Here we targeted a tropical liverwort, Marchantia inflexa, which grows in different light conditions on the island of Trinidad, the Republic of Trinidad and Tobago. We investigated intraspecific variation, including sex differences, of heat tolerance. This tropical liverwort is an ideal study candidate as they typically grow in cool, moist habitats along forested streams, and also in warm, dry, exposed roadside habitats. Forested streams have a closed canopy thus less light received, while road cuts are more open receiving more light during the day. Multiple vegetative thalli were collected from four streamsides and three roadsides, and their baseline physiologies (quantum efficiency of photosystem II or Fv/Fm) were noted. Samples were then subjected to a brief high temperature stress (55 0C for 45 minutes). Percent recovery was calculated by measuring Fv/Fm over a period of ten days. Additionally, light measures were estimated from each collection site using hemispherical canopy photographs. Following the field study, a common garden study was conducted with a small subset of plants to investigate the relationship between light intensity during growth and recovery from heat stress. Plants were heat stressed and assessed the recovery similarly as in the field. We found a significant correlation between the amount of light received and the percentage of recovery in field plants after experiencing heat stress. Sites with higher light exposure showed higher recovery from heat stress compared to sites with lower light. This pattern was significant in our common garden study as well. We are currently expanding this study to assess all sites in the common garden. This study provides evidence of genetic effects associated with light and heat stress responses in M. inflexa.

ABSTRACT. Photosynthetic tissue captures and converts light to carbohydrates. Photosynthetic traits are adapted to or can acclimate to increase photosynthetic efficiency in low light exposure or to mitigate the damaging effects of light in high light exposure. This linkage between light levels and traits is well established. When photosynthetic tissues take on reproductive function, trait changes will occur providing insight into how these traits relate to sex function. These changes, particularly if that are sex specific, have rarely been studied. To test for sex specific changes in photosynthetic tissues, we grew 25 males and 25 females of Marchantia inflexa in two light conditions. We assessed traits in vegetative and modified sexual thalli. The traits assayed were known to vary with light, including chlorophyll a/b ratios, carotenoid/chlorophyll ratios, dry weight/wet weight, and area/dry weight. We expected male and female vegetative thalli will not be dimorphic and have more carbon acquisition function relative to their respective sexual thalli. Higher acquisition function will be supported by a stronger light response in vegetative vs. sexual thalli. In addition, female sexual thalli will have a more of a carbon acquisition function than males because females require additional carbon to mature offspring. As expected, vegetative thalli strongly responded to increase light by decreasing chlorophyll, carotenoids, and area/dry weight while increasing dry weight/wet weight. The light response was not as strong for sexual thalli. Generally, females had smaller differences between thallus types (vegetative minus sexual) than males except for dry weight/wet weight. These differences are likely linked to sex function. For example, female sexual thalli are more associated with carbon gain than male sexual thalli and greater dry weight/wet weight is indicative of more scales that aid in sperm capture in females. This approach of detecting differences within the sexes between vegetive vs sexual tissue provided insight on how trait changes are linked to sex function.

ABSTRACT. Parent-offspring conflict is a fascinating situation where the parental generation must balance the resources it provides their offspring and the resources it reserves for its own fitness. Mosses are an ideal system to study parent-offspring conflict due to the sporophyte being physically attached and dependent on the gametophyte for the entirety of its life. Sporophytes have both anatomical and morphological features that may play a role in resource acquisition from the gametophyte, including the foot and water-conducting cells (hydroids, leptoids). These structures vary across moss species and this variation may influence the rate of resource acquisition (water and photosynthates). We will test the hypothesis that species with sporophytes that have larger capsules and longer stalks have higher transport rates. Additionally, we will quantify the anatomy and morphology of the foot and water-conducting cells for a panel of moss species to determine if there are correlations between these structures and transport rates. We predict that species with similar morphologies will have similar rates, while accounting for phylogenetic relatedness. Our ongoing studies to address these hypotheses will help to expand our understanding of these features and their roles in resource transport between gametophytes and sporophytes in mosses.

ABSTRACT. Parent-offspring conflict is the evolutionary tension that arises between parents and their offspring in terms of the allocation of resources. The moss life cycle presents a unique model for exploring the evolutionary dynamics of parent-offspring conflict. Sporophyte offspring are physically attached to and nutritionally dependent on the parental gametophyte for their entire lives. The primary objective of this project is to investigate the morphological structures that influence the parent-offspring conflict in mosses. The focus of this study will be the calyptra, a specialized parental structure that protects the developing sporophyte apex. We aim to explore the role of the calyptra in regulating parent-offspring conflict by quantifying calyptra morphology. We hypothesize that there is a trade-off between the thickness of the calyptra cuticle and the degree of hairiness on the calyptra as two overlapping strategies employed by the parental gametophyte to reduce the resource acquisition of the sporophyte offspring. To address these hypotheses, we are focusing on species of Polytrichaceae mosses that have a range of calyptra hairiness levels. To quantify calyptra morphology, both size and hairiness, we are employing dissection & pixel counting, while cuticle thickness will be measured using transmission electron microscopy. We predict that species with lower levels of hairiness on the calyptra will exhibit a thicker calyptra cuticle, while those with higher hairiness will display thinner cuticle, thus demonstrating a tradeoff in between cuticle thickness and hairiness. Furthermore, we are conducting a comprehensive analysis of the waxes present on the calyptra of the selected species using Gas Chromatography-Mass Spectrometry. This study will provide valuable insights into the variation that exists in calyptra morphology across the species and parent-offspring conflict in mosses.

ABSTRACT. The charismatic, abundant, and ecologically important genus Cladonia includes more than 500 accepted species and has a global distribution. The species-level taxonomy in Cladonia has long proved challenging, partially due to the extensive phenotypic plasticity displayed by many taxa. Some plasticity has recently been shown to be attributable to photobiont identity. In Cladonia, examples of essential morphological features used in species delimitation include podetia structure and size, soredia or apothecia presence, and squamule duration. The Cladonia chlorophaea group, composed of a variety of sorediate, cup forming Cladonia, poses a particular taxonomic challenge. Delimitation schemes range from many different stand-alone species with sharp delineations to a few broad, inclusive species under whose umbrella fall various chemotypes and morphological variants. We hypothesize that more robust species delineations lie somewhere in the middle and can be supported with comprehensive analyses of morphological measurements, secondary metabolite profiles, and whole genomes. The purpose of this inquiry into Cladonia chlorophaea is to provide an integrative analysis among three data types, with a special emphasis on comparative genomics. Using the Oxford Nanopore MinION platform, we sequenced full genomes of two Cladonia chlorophaea specimens, which were then assembled and annotated using standard protocols. Secondary metabolites were identified via thin-layer chromatography in solvent C. Scanning electron and light microscopy were used to characterize and quantify morphological traits. This study provides one piece of the taxonomic puzzle that is Cladonia chlorophaea and presents a clear path to providing a complete species description, not just for Cladonia, but for all lichens.

ABSTRACT. Plant conservation efforts in North America rarely include bryophytes. NatureServe is the authoritative source for biodiversity data in North America which is collected and maintained by the NatureServe Network of over 60 Member Programs (hereafter the Network). NatureServe and the Network (aka Nature Heritage Programs) focus conservation around three straightforward questions, what is it; where is it; and how is it doing. NatureServe maintains the taxonomy (what is it), by incorporating the latest information from floras, published literature, and the on-the-ground expertise of the Network. For bryophytes, answering “where is it” is often informed by published checklists, herbarium data, and expert opinion to determine the known bryophyte diversity in their jurisdiction. Checklists and floras often underestimate the total known diversity in a given state or region and often have outdated taxonomy. It is increasingly difficult for states, territories, and provinces, to know what taxa are present and how best to assess their rarity and conservation needs. Therefore, the most fundamental of the three guiding questions is a vetted consensus checklist of species that serves as the foundation for understanding the other two principles of conservation. This consensus bryophyte checklist would make bryophyte conservation assessments easier on NatureServe and Network Programs, however, building this list requires input from a community of experts. A first version of this collaborative effort resulted in an updated checklist of 4328 bryophyte taxa reported from North America. Using the most current taxonomic concepts, 2461 taxa have accepted names, 1779 are synonyms, and 88 are excluded from North America, although there remains many poorly known and unresolved taxa in the flora area. Applying the existing global rarity ranks for all accepted names, a small subset of the rarest taxa in North America were identified as taxa of critical conservation concern. We present here initial efforts to develop an updated consensus checklist and the names of the 20 rarest bryophytes in North America.

ABSTRACT. The ideological frameworks characteristic of western science limit the potential to holistically explore the intricacies of natural phenomena. Those frameworks prioritize ideas based on linearity, binaries, and anthropocentrism emphasizing hierarchies, productivity, and a hollow realization of objectivity. Here, we present alternative frameworks that aim to access scientific discovery from a systems perspective and incorporate interdisciplinary concepts. Such frameworks are integral tools in efforts to forge perspectives on scientific theories and systems that recognize the limitations of Science. Drawing from concepts in philosophy and social sciences, we illustrate the application of sympoiesis, process ontology, emergence, and narratives that evoke a ‘naked’—rather than ‘nude’—perception for reframing perspectives on natural systems. We synthesize these by deconstructing topical literature in ecology, health science, and education and making recommendations for use of language established outside of the western scientific lexicon. As white western scientists working towards broadening scientific perspectives, we recognize that communities and cultures that white imperialism has attempted to marginalize have long presented ways of being that reflect these approaches or are contrary to dominant ideologies. We aim to encourage flexibility and multiplicity of perspectives, highlight and maneuver biases, and emphasize the value of alternative frameworks and their applicability to research, ultimately fostering a dialogue that undermines oppressive systems attempting to suppress diversity of people and ideas in STEM spaces.

ABSTRACT. Cryptic species, which are distinct lineages lacking prominent distinguishing morphological or chemical characters, are common in lichen-forming fungi and have been reported in the most speciose family, Parmeliaceae. We studied the species delimitation in Parmelina that is a group of mainly asexually reproducing. In former studies the morphologically distinct P. pastillifera was found nested within a morphologically circumscribed P. tiliacea based on several loci. These studies demonstrated a relatively high genetic diversity within P. tiliacea sensu lato. We revisit the species delimitation in the group by analyzing single-nucleotide polymorphisms (SNPs) through genome-wide assessment using Restriction-Site-Associated sequencing and population genomic methods. Our results support previous studies and provide further insight into the phylogenetic relationships of the four clades found within the complex. Our analysis suggests a lack of gene flow among the clades, we recognize the four clades as distinct species, P. pastillifera and P. tiliacea sensu stricto, and two new species, P. clandestina sp. nov. and P. mediterranea sp. nov.

ABSTRACT. Embryophytes have undergone numerous re-invasions to aquatic habitats, impacting their morphological evolution. Despite the prominence of these transitions, comprehensive studies examining their phylogenetic implications and morphological adaptations remain scarce. We investigate these phenomena using the genus Fissidens, a diverse group of mosses encompassing both terrestrial and aquatic species. Our study integrates phylogenetic methods with morphological analyses to elucidate the evolutionary patterns within Fissidens and explore correlations between habitat transitions and morphological traits. Through extensive taxon sampling from herbarium specimens, DNA extraction, and sequencing, we construct robust phylogenetic trees using concatenated and coalescence methods. Our results reveal the non-monophyly of historically defined subgroups within the genus Fissidens, challenging prior classifications. Furthermore, ancestral state reconstructions suggest there have been multiple independent transitions to aquatic environments within the genus. Morphological analyses indicate that although variations in leaf length correlated with habitat moisture, phylogenetic relatedness diminishes this correlation. These findings better our understanding of the complexity of evolutionary transitions in embryophytes and emphasizes the need for further studies to refine taxonomic classifications and better understand morphological changes in response to ecological shifts. This study contributes to broader discussions on the evolutionary dynamics of aquatic transitions in both bryophytes and, more broadly, embryophytes and their ecological significance.

ABSTRACT. Guide to Liverworts of Oregon is an innovative state flora unlike any other in general use. A product of 40+ years of field, herbarium and laboratory work, all species documented or expected from the state are treated. The primary aim of the Guide is to provide illustrated dichotomous keys for identifying the species of liverworts growing naturally in the state of Oregon, U.S.A. The signal feature of the Guide is the use of high-resolution photomicrographs images to illustrate critical features defining the contrasting characters delineated in the pair of leads of each couplet. Each of the 174 species documented as found in Oregon is treated individually in the Guide. Each species page includes synonyms, a summary of the distribution and abundance of each species. Most have recognition hints with additional illustrations and comments on peculiarities and phylogenetic studies. Western Oregon is covered much more thoroughly than the eastern part of the state. With over 1,000 images, mostly full color photomicrographs, it illustrates most of the 174 species. The Guide will be broadly useful to botanists throughout the Pacific Northwest bioregion. Neither a textbook nor a manual, the Guide is intended to work as a companion to the California liverwort keys by Doyle and Stotler (2006) and the upcoming volume on liverworts in the Flora of North America (Volume 29). It includes indices to both species and genera, literature references and an illustrated glossary. As an HTML website, it is accessed through a by a web browser with clickable links to ensure users are always taken to the proper destination based on the choice of lead in a couplet. It allows step by step back tracking through the key, thumbnail images, and rapid navigation to indices, shortcuts, and glossary.

ABSTRACT. Adorning one long wall at the Ohio State University Herbarium (OS) are wood frames with glass fronts enclosing artfully arranged specimens of plants and fungi. These, along with larger, more elaborate panels of Ohio trees, were assembled by William A. Kellerman and Stella V. Kellerman for display at the World’s Columbian Exposition, a fair held in Chicago for six months in mid-1893. The Kellermans were botanists (William was a mycologist as well) who were remarkably energetic and wide-ranging in their scientific interests. The panels are an interesting snapshot of the flora of Ohio. While aesthetics and enthusiasm for particular plants and fungi may have played a major role in their selection by the Kellermans, the panels were indeed portrayed to fairgoers as representatives of the native flora at that time. Forty-five lichen species are presented, equally distributed among five 18 x 22-inch panels. They depict a biota rich in old-growth forest species, some of which are rare or absent in the contemporary lichen flora of Ohio. For instance, a set consisting of large foliose lichens found on bark includes Ricasolia quercizans, of which there are only six post-1965 specimen records in the state, and Lobaria pulmonaria, of which there are none. In addition to the Kellermans, several prominent figures in early North American lichenology and Ohio botany including Bruce Fink, Ernest Bogue, and William Werner were active in around the time the panels were made. Their specimen records have contributed to our knowledge of the state’s lichen flora over a century ago and help us interpret the significance of these panels as a reflection of late 19th-century Ohio lichen diversity.