Mary Barkworth

Utah State University | USU · Department of Biology

These proposals would make attendance at a Nomenclature Section open to a wider audience and therefore more democratic.

The Special-purpose Committee on Virtual Participation in the Nomenclature Section was established by the XIX International Botanical Congress (IBC) in Shenzhen, China in 2017, with the mandate "to investigate the possibility of and mechanisms for virtual participation and voting in the Nomenclature Section of an International Botanical Congress vi...

Badakhshan, situated in Pamir is one of Eurasia's biodiversity hotspots. Research shows that Badakhshan has 95 narrowly endemic species that are not found in other areas of Tajikistan and Afghanistan. Of these, 50 species grow only in the Tajik part, 36 species-only in the Afghan part, and 9 are found in both parts of Badakhshan. There are 52 pregl...

Evolvulus nummularius (L.) L., a member of the Convolvulaceae, is native to Mexico and South America but nowadays grows around the world in many tropical and subtropical regions. Its presence in Pakistan, where it has become naturalized, is reported here for the first time. It was first discovered in Pakistan in the Jhok Reserve Forest in Lahore ci...

The mainly Australian grass genus Austrostipa with ca. 64 species represents a remarkable example of an evolutionary radiation. To investigate aspects of diversification, macro- and micromorphological variation in this genus we conducted a molecular phylogenetic and scanning electron microscopy (SEM) analysis including representatives from all of i...

We have databased information on grass distributions in North America from a variety of sources in connection with the Manual of Grasses for the Continental United States and Canada project. These data, and treatments submitted by the contributors, indicate that the Manual region (= continental United States and Canada) has 896 native grass species...

In the presentation, I suggested that a combination of OPenHerbarium and KeyBase could be used to develop and provide access to a continuously updated version of the Flora of Iran, aid in producing high quality research, increase outreach. I also drew attention to some valuable international web sites for botanists.

Regional floras are primary resources for plant identification, an essential step in developing conservation strategies. They also provide students with a scientific window on the plants around them and help them learn botanical terminology, but they are expensive to maintain and publish. We are developing web-accessible updates for different flora...

My goal was to encourage use of digital technology in developing floras. It will not cut the time to prepare treatments; it can display them more rapidly, expand their visibility, enable including them to include many features not possible in print floras, and create resources for use (with appropriate credit) in other floras and in other research...

Symbiota, the most used biodiversity content management system in the United States, has helped mobilize over 35 million specimen records from over 750 natural history collections via 40+ separate installations. Most Symbiota records come from natural history collections but some Symbiota instances also incorporate records from observations, images...

In 2017, funding from the Biodiversity Information Fund for Asia accelerated data mobilization and georeferencing by Pakistani herbaria. The funding directly benefited only two herbaria but, by the end of the project 9 herbaria were involved in sharing data, 2 through GBIF (ISL 2019, SINDH 2019; codes according to Index herbariorum) and 6 others (B...

A new species of Aloe (Asphodelaceae) is described from Somaliland. It differs from other species in forming large clumps and in having sap that is initially yellow but quickly turns bright red and then dark red or reddish-brown, paniculate red-flowered inflorescences and uniformly coloured leaves with red teeth. Its recognition raises the number o...

Increasing the number of occurrence records available for biodiversity research requires developing efficient pipelines from collectors and observers to data aggregators and then marketing those pipelines to biodiversity researchers. To be effective, these pipelines must recognize that in many countries, internet access is slow, intermittent, or ex...

The dwarf forms of Stenopoa (height 5–15 cm) which are common in alpine belt of the Pan-Himalayas, represent one of the most problematic groups in the genus. Ten dwarf species of Stenopoa have been recorded for the area under consideration: P. attenuata Trin, P.glauca Vahl, P. litvinoviana Ovcz., P. albertii Regel, P. koelzii Bor, P. lahulensis Bor...

Most people in the Swat valley of northwest Pakistan practice subsistence farming, supplementing their income by collecting and selling wild harvested plants for use in herbal medicine. Previous work showed that the collectors did not know the potential long-term impacts of collecting wild plants. We hypothesized that establishment of ex situ culti...

This is not a research project per se. The Foundation is about developing, in Somaliland, a physical and educational infrastructure that will enable Somalilanders to engage in biodiversity research without having to leave the country. The newsletter contains information on our activities. The decision to form a foundation to support our work was ma...

The Melbourne Congress of 2011 authorized a Special Committeeon Registration of Algal and Plant Names (including fossils), whichwas established the following year (Wilson in Taxon 61: 878–879.2012). Its explicit mandate was “to consider what would be involved inregistering algal and plant names (including fossils), using a procedureanalogous to tha...

The Special Committee on By-laws for the Nomenclature Section was established at the XVIII International Botanical Congress (IBC) in Melbourne in 2011, with the mandate to formalize the procedures by which changes to the Code are considered and voted upon by the Nomenclature Section, and to report to the XIX IBC in Shenzhen in 2017. With the wider...

The Special Committee on Registration of Algal and Plant Names (including fossils) was established at the XVIII International Botanical Congress (IBC) in Melbourne in 2011, its mandate being to consider what would be involved in registering algal and plant names (including fossils), using a procedure analogous to that for fungal names agreed upon i...

We investigated the lemma micromorphology of 17, primarily Siberian, species of Stipa using scanning electron microscopy (SEM). All the species had variants of the micromorphology considered typical for Stipa but each had a unique combination of characteristics, enabling its identification solely on the basis of its lemma micromorphology. Phenetic...

Poverty is pervasive in the Swat Valley in northwestern Pakistan, and most people survive by farming small landholdings. However, many supplement their meager subsistence earnings by collecting and selling plant material for use in herbal medicine. This material is wild-harvested, but collectors seem not to fully appreciate the potential value of t...

We present a visual synopsis of distribution data derived from three floras via http://OPenHerbarium.org, a website built using Symbiota (http://symbiota.org). One flora (Flora of Pakistan) provides specimen citations and the other two (Flora of Somali and Flora of Ethiopia and Eritrea) area checklists. The data were extracted by inmates in a count...

Acceptance of a name is the ultimate provision for valid publication of new names under the International Code of Nomenclature for algae, fungi, and plants (McNeill & al. in Regnum Veg. 154. 2012). This is stressed in Art. 33.1, which requires that, after fulfilling all the other conditions of valid publication (if fulfilled separately), a name mus...

We evaluated the effects of long-term flow alteration on primary-producer assemblages. In 1962, Flaming Gorge Dam was constructed on the Green River. The Yampa River has remained an unregulated hydrologically variable river that joins the Green River 100 km downstream from Flaming Gorge Dam. In the 1960s before dam construction only sparse occurren...

The International Triticeae Symposia were initiated to encourage scientists working on different aspects of the Triticeae2 to share information and examine the distant relatives of its cereal species. There have now been seven symposia, each in a different country. The scope of these symposia is briefly reviewed. The merits of the symposium series...

Piptochaetium fuscum (Nees ex Steud.) Barkworth, Ciald., & Gandhi, a new combination replacing Piptochaetium setosum (Trin.) Arechav. Abstract A new name, Piptochaetium fuscum, is provided for a taxon hitherto known as Piptochaetium setosum (Trin.) Arechav. Morphological, anatomical, and molecular studies that argue against including Piptochae-tium...

We show that of four previously unrecorded, but recently unearthed names in Aloe L. (Asphodelaceae: Alooideae), none has an impact on the species-rank nomenclature of the genus as currently accepted. Although nomenclatural stability is not here impacted, we argue that such long-hidden names that are now visible as part of the nomenclature applicabl...

The goal of the US Virtual Herbarium (USVH) project is to digitize (database, image, georeference) all specimens in all US herbaria, enabling them to be made available through a single portal. Herbaria house specimens of plants, fungi, and algae, so USVH will offer a rich portrait of biodiversity in the US and in the other countries represented in...

We conducted a detailed study of the morphological and cytological variation in seven populations of the Poa orinosa complex along an ecological gradient in northeastern China. Three of the populations were at different elevations in wooded habitats; three were in habitats dominated by grasses other than Poa; and one was in a shrub–steppe habitat....

Thirty-seven alleles encoded by eight loci from six enzyme systems were numerically analyzed in taxa of Thinopyrum, Lophopyrum, Trichopyrum, and Pseudoroegneria. Thinopyrum and Lophopyrum were similar, and both were distant from Pseudoroegneria. This is consistent with anatomical and genomic evidence, but conflicts with that from morphology. The on...

The morphology and awn anatomy of the large-glumed species of Stipa occurring in Canada were examined. Numerical analysis of the data indicates that S. spartea var. spartea and S. spartea var. curtiseta are very distinct taxa differing not only in many of their quantitative characters but also in nodal pubescence, ligule shape, and pubescence of th...

Stipa nelsonii, more commonly but incorrectly known as S. Columbiana, is a wide ranging species of western North America, characterized by a short, pubescent palea and a hirtellous awn. Initial numerical analyses, using unweighted morphological data, suggested that three infraspecific taxa existed but with different methods of analysis there was a...

We endorse recognition of four morphologically and cytologically distinct genera for Australasia's native Triticeae: Australopyrum, Stenostachys, Anthosachne and Connorochloa. To encourage adoption of this recommendation, we present a key to all genera of Triticeae found in Australasia, descriptions of the native genera, keys to their species, the...

Our goal was to determine whether the genomic groups of perennial species Triticeae having solitary spikelets could be identified morphologically and, if so, to construct identification keys that could be used for this purpose. If so, it would strengthen the argument for recognizing such groups as genera. We conducted Discriminant and Random Forest...

We describe a new genus in the Triticeae, Connorochloa Barkworth, S.W.L. Jacobs, & H.Q. Zhang, which currently contains only one species, Connorochloa tenuis (Buchanan) Barkworth, S.W.L. Jacobs, & H.Q. Zhang. Connorochloa differs from all other members of the Triticeae in having a peduncle that elongates greatly after anthesis, causing the culms to...

The grass tribe Triticeae has been the focus of many research programs because its inclusion of wheat, barley, and rye makes it of critical importance to the world’s food supply, an importance that is enhanced by the many other species that are important for forage and soil stabilization. One consequence of the tribe’s importance is that scientists...

We conducted phylogenetic analyses of molecular data (ITS, trnH–psbA, trnC–trnL, and trnK–rps16) for 71 species of stipoid grasses. Of these species, 30 are native to South America, seven are native to Mexico and/or the southwestern United States, 15 to other parts of North America, 12 to Eurasia and/or the Mediterranean region, and seven to Austra...

The Bromus carinatus complex comprises several cleistogamous taxa that have been recognized at a variety of taxonomic levels. Our study focused on three taxa: B. carinatus s.s., B. marginatus, and B. polyanthus, that have received varied taxonomic treatment. We mapped the collection sites of 673 specimens belonging to these taxa to determine whethe...

Grasses of the Intermountain Region is a modification of the two grass volumes of the Flora of North America (FNA). It is designed for identifying members of the Poaceae in the region between the Sierra Nevada and Rocky Mountains, and is intended for use by botanists working with the grasses in this intermountain region of North America. The reduct...

JARVIE, J. K. & BARKWORTH, M. E., 1992. Anatomical variation in some perennial Triticeae. Cross-sectional anatomy of glumes and leaf blades was examined in 22 taxa of the perennial Triticeae. The taxa included diploids and polyploids based largely on various combinations of the E, J and S genomes. The objective was to determine how much correlation...

JARVIE, J. K. & BARKWORTH, M. E., 1992. Morphological variation and genome constitution in some perennial Triticeae. A numerical analysis of species of five genomically defined genera of the Triticeae was undertaken, based on 42 morphological characters and 142 operational taxonomic units (OTUs). The primary goal was to determine the degree of cong...

The history of the Triticeae is replete with changes in generic concepts, caused by taxonomists' struggle with the task of representing its highly reticulate history within the hierarchical classification system demanded by scientific nomenclature. Disagreement over the criteria used for delimiting taxa is an additional complication. Linnaeus' goal...

Internal transcribed spacer (ITS) sequences have been determined for a wide range of stipoid grasses (Poaceae, Pooideae, Stipeae). Nardus was confirmed as the most appropriate outgroup. Anisopogon is consistently included among the stipoid genera. Lithachne and Oryza form a clade and are clearly not close to Stipeae, and there is no support for inc...

Eighteen Glyceria species grow in the United States and Canada, with 16 being native to the region. We used data from morphology and three chloroplast DNA intergenic regions to address taxonomic questions concerning Glyceria in North America, particularly the status of G. declinata, G. occidentalis, G. fluitans, G. striata, and G. elata in western...

Grasses are the world's most important plants. They are the dominant species over large parts of the earth's land surface, a fact that is reflected in the many different words that exist for grasslands, words such as prairie, veldt, palouse, and pampas to mention just a few. As a group, grasses are of major ecological importance, as soil binders an...

Grasses are the world’s most important plants. They are the dominant species over large parts of the earth’s land surface, a fact that is reflected in the many different words that exist for grasslands, words such as prairie, veldt, palouse, and pampas to mention just a few. As a group, grasses are of major ecological importance, as soil binder...

One new hybrid genus, ×Pascoelymus = Pascopyrum × Elymus, and 12 new combinations are presented for North American grasses. Six of the new combinations are for hybrids in the Triticeae. Stipa arnowiae is transferred to Achnatherum and Hystrix californica (≡ Elymus californicus) to Leymus. Agropyron riparium is recognized as a subspecies of Elymus l...

A new genus of Stipeae (Poaceae), Amelichloa, is described. It differs from other genera in the tribe in the woody, sharp tips of it basal leaves, the presence of smooth longitudinal ribs on its caryopses, its persistent stylar bases and in the frequent presence of cleistogamous panicles in the axils of its basal leaf sheaths. There are five specie...

Morphological and anatomical arguments are presented for recognizing one new genus, Celtica, and one previously described genus, Macrochloa, in the Stipeae. The species of both genera, each of which is now monotypic, were included by Kunth in his circumscription of Macrochloa. They are currently placed either in Stipa or Achnatherum, but are clearl...

We support Kerguélen's (1977, 1987) assertion that both Lamarck (1798) and Willdenow (1809) independently published the identical name Panicum geniculatum and that P. Beauvois (1812) based his Setaria geniculata on Willdenow's name. The type collections of Lamarck's and Willdenow's names are different, but were from the same locality and belong to...

This reference is to one of two volumes in the Flora of North America north of Mexico series. Utah State University holds the copyright to both volumes. The content of the volumes, and updates to them. are being presented via a combination of KeyBase (for the identification keys) and OpenHerbarium (for the descriptions and illustrations).

Barkworth, M. E. & Torres, M. A.: Distribution and diagnostic characters of Nassella ( Poaceae: Stipeae ). – Taxon 50: 439–468. 2001. – ISSN 0040‐0262. Nassella sensu lato includes 116 species, making it one of the largest genera in tribe Stipeae. Argentina has the largest number of species, 72, with the greatest concentration being in the northwes...

Accurate communication of scientific research about biological entities is critically dependent on correct identification and naming of the entities involved. This is not a simple task, particularly in a group such as the Triticeae in which there are still many taxa whose limits are only poorly understood. Even if the names used are appropriate at...

Herbarium specimens identified as Agropyron yukonense or one of its synonyms consistently differ from the holotype and protologue of that name and resemble each other in their stiff, involute leaves, narrow, dark cauline nodal bands, and pilose paleas. This suggests that the non-holotype plants represent a new species. Cytogenetic analysis of root...

Jacobs, S. W. L., Everett, J. & Barkworth, M. E.: Clarification of morphological terms used in the Stipeae (Gramineae), and a reassessment of Nassella in Australia. – Taxon 44: 33‐41. 1995. – ISSN 0040‐0262. Terms used for describing the apical regions of the lemma of the Stipeae have been used inconsistently in the past. Those terms are listed and...

Nassella Desvaux es un género de la tribu Stipeae, descrito originalmente para especies de América Central y Sudamérica, que consiste de plantas con flósculos obovados, gibosos, con callo obtuso, lema no estriada con márgenes superpuestos y aristas fácilmente deciduas. Pohl (1980), Barkworth y Everett (1987) y Barkworth (1990) definieron un concept...

The taxonomic history of Nassella Desv. is reviewed and its circumscription expanded to include all species of Stipeae with strongly overlapping lemma margins; lemma apices that are fused into a crown; paleas that are highly reduced, ecostate, and glabrous; long epiblasts; and lemma epidermes with very short fundamental cells having silicified cell...

Stipa clandestina Hackel, a native of northern Mexico, has been found in Texas and may become a serious weed problem for range managers in the southwest. Its sharply pointed leaves and tussock-forming habit make it unpalatable to cattle, but in Mexico it tends to increase with heavy grazing or disturbance. Actively growing plants can be killed by a...

Identifying juvenile grasses is especially difficult because their characteristics are greatly affected by growing conditions. One problem, which affects both computer-based identification systems and written identification keys, is the inability of users to select the correct alternatives for some morphological characters or structures. This study...

Two new taxa, Piptochaetium avenacellum Barkworth from Tamaulipas and P. brevicalyx subsp. flexuosum Barkworth from Durango, are described. Descriptions, illustrations, and detailed distributional data are given.

Dewey and Löve have suggested that generic limits in the Triticeae should be determined by the genomic data, taxa with different genomic constitutions being placed in different genera. According to this interpretation, nine genera of perennial Triticeae occur in North America. Five of these ( Critesion, Elymus, Leymus, Pascopyrum , and Pseudoroegne...

Morphological studies of populations belonging to three taxa of Leymus revealed that L. salinus comprises L. salinus subsp. salinus and L. salinus subsp. salmonis. These subspecies are geographically separated: subsp. salinus occurs in eastern Utah, northern Arizona, southwestern Wyoming, and western Colorado whereas subsp. salmonis occurs in Idaho...

Leymus Hochst., a segregate genus of Triticeae, can be recognized morphologically and genomically. Its members exhibit all or all but one ofthe following morphological characterstics: rhizomatous habit; unawned, short, often stiffly subulate, glumes that tend to lie opposite the sides rather than the midveins of the lemmas; unawned, or only shortly...

Leymus Hochst., a segregate genus of Triticeae, can be recognized morphologically and genomically. Its members exhibit all or all but one of the following morphological characterstics: rhizomatous habit; unawned, short, often stiffly subulate, glumes that tend to lie opposite the sides rather than the midveins of the lemmas; unawned, or only shortl...

Vegetation growing on soils derived from dolomite and quartzite parent material on open slopes in the Bear River Range of northern Utah and southern Idaho were compared using data from 8 pairs of plots having similar slope, elevation, and aspect. Detrended correspondence analysis and cluster analysis revealed that composition and cover of species w...

Oryzopsis kingii is transferred to Ptilagrostis as P. kingii on the basis of its morphological, anatomical, ecological, and cytological similarity to other members of that genus. In addition, P. porteri is transferred to P. mongholica as P. mongholica subsp. porteri. Stipa stillmanii, whose inclusion in Ptilagrostis has also been suggested, is reta...

Epiblast length and shape were examined in 39 species of the Stipeae, 29 of which are native to North America. In most species of Stipa examined the epiblast equalled or exceeded the coleoptile and was acute with or without a small V‐shaped notch at the apex. In contrast, in most species of Oryzopsis the epiblast extended no more than three‐quarter...

The characteristics of the lectotype of Stipa columbiana Macoun are reviewed in detail and shown to include those generally considered diagnostic of the species S. lemmonii (Vasey) Scribner but not those diagnostic of S. columbiana auct. Thus the name S. columbiana Macoun must either be rejected, as proposed earlier or, because it has priority, app...

Abaxial epidermes of basal leaves of 49 species of Stipeae, almost all North American, were examined. It was not possible to recognize individual species by their epidermal characters but some taxonomically interesting correlations were found. Shape of costal silica bodies and numbers of costal and intercostal cell files were the most useful taxono...