Illinois Natural History Survey Research Articles

Morphological variation in the vomer of aquatic and terrestrial spelerpini salamanders.

The vomer is an important tooth-bearing cranial bone in the lungless salamanders (Caudata: Plethodontidae) that serves different functional roles in aquatic versus terrestrial feeding. Vomerine tooth rows that run parallel with the maxillary teeth are thought to help grasp prey while expelling water from the mouth, while posterior extensions of the tooth row may help terrestrial taxa bring prey down the throat. We hypothesize that these two general morphological types will correlate with the habitat (aquatic vs. terrestrial) of adult salamanders. Alternatively, variation in form may be due to taxonomic effects, such that closely related species will have similar vomer morphology regardless of adult habitat. To test this hypothesis, we examined vomer shape on a set of species of the morphologically diverse tribe Spelerpini, in which two of the five genera (Eurycea and Gyrinophilus) include both aquatic and terrestrial species. Data were collected using micro computed tomography (micro-CT) scans from specimens from the Field Museum of Natural History and the Illinois Natural History Survey; additional data was obtained from public online repositories including Morphosource.org. Two-dimensional geometric morphometric analyses were performed to capture shape variation of both the vomer and the vomerine tooth row. We found clear separation between aquatic and terrestrial taxa, with most of the variation due to differences in the vomerine tooth row. Differences ascribed to habitat use likely correspond to feeding behavior, and the functional role of the vomer in prey processing warrants further investigation in this species-rich salamander family.

A century of Illinois hover flies (Diptera: Syrphidae): museum and citizen science data reveal recent range expansions, contractions, and species of potential conservation significance.

Hover flies of the family Syrphidae are a highly diverse group of insects that exhibit varied life histories and provide numerous ecosystem services. Despite their importance, they are highly understudied, and many biological and distributional patterns remain unknown in regions like the midwestern United States. Data from specimens exist in regional insect collections but is largely undigitized and thus inaccessible to much of the scientific community. Here, we report our efforts to identify, recurate, and digitize thousands of specimens from the Illinois Natural History Survey Insect Collection. We then combine these data with existing datasets to compile a comprehensive checklist of Illinois hover fly fauna, assess for temporal range expansion/contraction trends, and identify species of potential conservation significance. All total, the over 20,000 specimens/records we examined revealed 209 species within 71 genera and all 4 subfamilies of Syrphidae to have ever occurred in Illinois. Based on previously published data, 68 of these species are new Illinois state records and 36 expand the previously known range significantly. Numerous species found in Illinois historically have only recently been reported further north, while others of historically southern distribution appear to be extending their range northward, possibly due to anthropogenic factors like climate change. Furthermore, 73 species have not been reported in Illinois since at least 1995, and 27 are deemed to be of potential conservation significance with few to no recent records in the Midwest or elsewhere. Our findings illustrate the importance of routine expansion, curation, and digitization of natural history collections.

Featured collection introduction: Water resources planning and management under changing conditions—Experience of Illinois

Pioneering work by John Stall on hydraulic geometries of streams and rivers was completed in the 1960s Water and Atmospheric Research Monitoring (WARM) program at the ISWS expanded data collection to define the environmental and socio-economic impacts of weather and climate impacts, including: The ISWS, along with the Illinois Natural History Survey (est. 1861) and Illinois State Geological Survey (est. 1905), were transferred out of the University of Illinois in 1917 to be administered by the Illinois Department of Registration and Education, eventually being transferred to the Illinois Department of Energy and Natural Resources and then to a new Illinois Department of Natural Resources. In 2008, the Scientific Surveys came home to where it all started, the University of Illinois, under the umbrella of the Prairie Research Institute with the addition of the Illinois Sustainability and Technology Center and Illinois State Archeological Survey. Together, the Prairie Research Institute has over 800 scientists, technicians, post-docs, research affiliates, visiting scholars, students, and administrative support staff, conducting transformative science that benefits the people, economy, and environment of Illinois, the nation, and the world. From their inception, the Scientific Surveys have always been located on the University of Illinois campus and continues to capitalize on the mutual benefits of collaboration with faculty and staff. The papers presented in this special issue marking the 125th anniversary founding of the ISWS are but a representation of the current contributions and research being conducted by ISWS scientists and colleagues, aiming to demonstrate what Illinois experiences in water resources planning and management under changing conditions, especially changing climate. They build on water supply planning legacy by incorporating future demands and climate uncertainties in Illinois, including the major updating of Illinois precipitation frequency standards. The theme of understanding uncertainties and bias continues in evaluating groundwater static head measurements to understand water-level variability. Of course, projecting climate change impacts is paramount to many water resource issues and authors discuss which climate ensemble approaches produce less uncertain climate model outputs. Nutrient losses in US agricultural lands are an issue not only for loss of crop production but downstream impacts. Winter cover crops have much promise for reducing nitrate, phosphorus, and sediment loads. Authors present possible detrimental impacts on storage volumes for downstream reservoirs in drought years. An Illinois River watershed analysis presents evidence that spatial and temporal shift in phosphorus loading affects recent increases in phosphorus despite point and nonpoint source efforts. The ISWS has long-term datasets which contributed to improved model calibration to capture chloride accumulation in shallow aquifers. Reservoirs serve populations and industry so understanding outflows from them is important for water resource planning and management. Comparing performance of three machine learning models shows promise for simulating reservoir outflow. Finally, colleagues in Illinois and China test a theoretical framework to better understand bivariate return periods of hydrological events, which is important for design criteria of hydraulic structures. The ISWS continues to evolve and adjust research needs, as demonstrated by the first 125 years, and look forward to providing science-based information to societies in the next 125 years. For further reading on ISWS history, the following publications are recommended:

Northern Sunfish (Lepomis peltastes) Distribution in Illinois

The recent elevation of Lepomis peltastes (Northern Sunfish) as a separate species from L. megalotis (Longear Sunfish) has resulted in an incomplete understanding of the species' distribution in Illinois, as most occurrence records cannot differentiate the 2 species. We evaluated Northern Sunfish and Longear Sunfish specimens to identify morphological characteristics that could differentiate the 2 species; relative body depth, relative opercular flap length, and pectoral fin ray count were most useful. We reevaluated 867 Longear Sunfish specimens from the Illinois Natural History Survey Fish Collection and identified 103 as Northern Sunfish. Based on distribution of these specimens, it is probable that Northern Sunfish occur in 14 basins in the eastern half of Illinois, a range that extends farther south than was previously estimated.

The Persistence of State-Listed Endangered and Threatened Seed Plants in Populated Illinois Landscapes

The state of Illinois has few natural areas remaining due to anthropogenic changes caused by agriculture, industry, and urbanization. This study investigates the seed plants at the greatest risk of extirpation from Illinois, the state-listed endangered and threatened species, and their occurrence relative to land use. The Illinois Endangered Species Protection Board and the Illinois Natural History Survey chronicle the occurrence and distribution of state-listed endangered and threatened species. We extracted the number of endangered/threatened species per county from these records. We also calculated the proportion of land cover per county for anthropogenic, non-anthropogenic, and protected areas. Using these data, we modeled the distribution of state-listed endangered and threatened seed plants as a function of land cover and human population density. Our study revealed that many endangered plant species are persisting in counties with high levels of human population density. A high degree of agricultural land cover was negatively associated with the presence of endangered/threatened seed plant species. We provide statistical evidence that endangered/threatened species are persistent in highly populated areas, given that there are protected lands with adequate habitat for them to grow. These results underscore the importance of protecting natural habitats. Urban development has preserved some of these habitats by establishing protected lands that allow the continued existence of many species. The role that protected lands play in the conservation of biodiversity is crucial to prevent extirpation of endangered/threatened seed plant species in Illinois.

Taxonomy of the leafhopper genus Angolaia (Hemiptera: Cicadellidae: Deltocephalinae: Selenocephalini) with description of a new species from Zambia.

The African leafhopper genus Angolaia Linnavuori & Al-Ne'amy, 1983 (Cicadellidae: Deltocephalinae: Selenocephalini: Selenocephalina) is reviewed, including description of the new species, Angolaia picea sp. nov., from Zambia. An updated checklist with distribution and a key to males in this genus are also provided. Type specimens of this new species are deposited in the Illinois Natural History Survey, University of Illinois, Champaign, Illinois, USA (INHS).

Computational metadata generation methods for biological specimen image collections

Metadata is a key data source for researchers seeking to apply machine learning (ML) to the vast collections of digitized biological specimens that can be found online. Unfortunately, the associated metadata is often sparse and, at times, erroneous. This paper extends previous research conducted with the Illinois Natural History Survey (INHS) collection (7244 specimen images) that uses computational approaches to analyze image quality, and then automatically generates 22 metadata properties representing the image quality and morphological features of the specimens. In the research reported here, we demonstrate the extension of our initial work to University of the Wisconsin Zoological Museum (UWZM) collection (4155 specimen images). Further, we enhance our computational methods in four ways: (1) augmenting the training set, (2) applying contrast enhancement, (3) upscaling small objects, and (4) refining our processing logic. Together these new methods improved our overall error rates from 4.6 to 1.1%. These enhancements also allowed us to compute an additional set of 17 image-based metadata properties. The new metadata properties provide supplemental features and information that may also be used to analyze and classify the fish specimens. Examples of these new features include convex area, eccentricity, perimeter, skew, etc. The newly refined process further outperforms humans in terms of time and labor cost, as well as accuracy, providing a novel solution for leveraging digitized specimens with ML. This research demonstrates the ability of computational methods to enhance the digital library services associated with the tens of thousands of digitized specimens stored in open-access repositories world-wide by generating accurate and valuable metadata for those repositories.

Annotated checklist of the primarily freshwater fishes of Guyana

Guyana, located in northern South America north of Brazil between Venezuela and Suriname, includes portions of the Orinoco, Amazon, and Courantyne river basins, a majority of the Essequibo River Basin, and all of the Berbice and Demerara river basins. Partly as a consequence of historical and contemporary drainage complexity, Guyana has a remarkably diverse freshwater fish fauna. Here, we compile the first comprehensive list of Guyana's freshwater fishes, totaling some 657 species-level taxa (97 first records, 117 endemics and at least three introduced species), based on photographic records, published reports, and over 145,000 type and non-type specimens in 29 museum collections. The IUCN conservation status for each species is provided. We separately list an additional 151 undocumented species that are possibly or likely present in Guyana based on their adjacent distributions in either the Orinoco River Delta in Venezuela or the Courantyne River in Suriname. The largest holdings of fish specimen vouchers and frozen fish tissues from Guyana are housed at the Royal Ontario Museum, Toronto (ROM), Auburn University Museum, Auburn (AUM), University of Michigan Museum of Zoology, Ann Arbor (UMMZ), and the Academy of Natural Sciences of Drexel University, Philadelphia (ANSP). Additional important collections of Guyanese fishes are deposited at the Centre for Study of Biological Diversity, Georgetown, Guyana (CSBD), Field Museum of Natural History, Chicago (FMNH), Illinois Natural History Survey, Champaign (INHS), The Natural History Museum, London (NHMUK, formerly BMNH), Oregon State University, Corvallis (OS), and the US National Museum, Washington (USNM). Despite the many collections that have been made in Guyana, many species still lack vouchered specimens or tissues, and many more species require formal description.

Nonindigenous Aquatic Mollusks in Illinois

Nonindigenous aquatic species (NAS), some of which are referred to as aquatic invasive species (AIS) or non-native aquatic species, are those aquatic organisms that have become established beyond their native ranges. They often inhabit a variety of habitats and physicochemical conditions, reach high densities, and alter ecosystem function. Understanding the distribution of nonindigenous aquatic species is vital to protecting native biodiversity in invaded ecosystems. A search of museum collections, literature accounts, and field surveys conducted in recent years by biologists from the Illinois Natural History Survey, Illinois Department of Natural Resources, and other agencies revealed 13 nonindigenous aquatic mollusk species reported to occur in Illinois. Ten species (five bivalves and five gastropods) have viable reproducing populations. One species, the Big-eared Radix Radix auricularia (Linnaeus, 1758), is no longer extant in Illinois, and two species, the European Stream Valvata Valvata piscinalis (Müller, 1774) and European Fingernail Clam Sphaerium corneum (Linnaeus, 1758), have an unknown status. Some species, such as the Basket Clam Corbicula fluminea (Müller, 1774), Zebra Mussel Dreissena polymorpha (Pallas, 1771), and Chinese Mysterysnail Cipangopaludina chinensis (Gray in Griffith and Pidgeon, 1833), are widespread and abundant. However, other species like the Mottled Fingernail Clam Eupera cubensis (Prime, 1865) and New Zealand Mudsnail Potamopyrgus antipodarum (Gray, 1843) are currently restricted to a particular location or drainage. Other nonindigenous aquatic mollusks with the potential for becoming established in Illinois or border waters are also discussed.

The potential of semi-structured citizen science data as a supplement for conservation decision-making: Validating the performance of eBird against targeted avian monitoring efforts

Methods are being developed to capitalize on citizen science data for research and monitoring, but these data are rarely used within established decision-making frameworks of wildlife agencies. Citizen science data are often collected at higher resolution and extent than targeted monitoring programs, and may provide complementary information. Here, we demonstrate that carefully filtered semi-structured citizen science observations, when paired with targeted survey data, can produce ecological predictions at higher resolution and extent than targeted surveys alone, and both datasets can represent complementary aspects of species' ecology. We present case studies demonstrating how citizen science data can enhance or supplement decision-making of government and conservation organizations. First, we show how the continuous spatial coverage of citizen science projects, when coupled with targeted surveys, can improve estimates of metrics used by the U.S. Fish and Wildlife Service in regulatory processes to estimate population size, and inform take limits of federally managed species nationwide. Second, we show that the spatial coverage of citizen science accommodates dynamic avian space use patterns during key times of the year, relative to standardized monitoring protocols carried out by the Illinois Natural History Survey. Lastly, we demonstrate that citizen science information can replicate estimates of migratory chronologies for the Illinois Natural History Survey and the U.S. Fish and Wildlife Service for some waterfowl species, and in some contexts can supplement missing data on abundance. These findings illustrate the value of integrating validated information from semi-structured citizen science into the current evidence base used to justify, inform, and evaluate conservation decision-making.

New State and Provincial Records for Some Nearctic True Bugs (Hemiptera: Heteroptera) from the Illinois Natural History Survey Insect Collection

New State and Provincial Records for Some Nearctic True Bugs (Hemiptera: Heteroptera) from the Illinois Natural History Survey Insect Collection

Machine learning with high-resolution aerial imagery and data fusion to improve and automate the detection of wetlands

Wetlands serve many important ecosystem services, yet the United States lacks up-to-date, high-resolution wetland inventories. New, automated techniques for developing wetland segmentation maps from high-resolution aerial imagery can improve our understanding of the location and amount of wetlands. We assembled training and testing data sets (patch sizes of 28 × 28 m2 and 56 × 56 m2) of high-resolution aerial imagery of wetlands using Illinois Natural History Survey wetland location data and National Agricultural Imagery Project data. Each patch was labeled as wetland or non-wetland. To augment these data sets with additional information, we incorporated digital surface and digital terrain models and topographic wetness index data in the same two patch sizes. Subsequently, we evaluated convolutional neural network (CNN) and Gaussian process-based machine learning methods to produce wetland segmentation maps. We developed the best performing method into a new CNN algorithm, WetSegNet. It exhibited an area under the curve of 98% when used with 56 × 56 m2 patch sizes. WetSegNet developed reliable wetland segmentation maps in test cases in which wetlands would have gone undetected using only the National Land Cover Database. The development of WetSegNet exemplifies the types of data sets and methods that are needed to accelerate the use of high-resolution aerial imagery towards an improved understanding of wetlands. This algorithm could be used by state and federal agencies or other groups to identify wetlands with higher accuracy and at a finer scale than previously possible.

Preliminary Illinois Bee Species Checklist (Hymenoptera: Apoidea) and use of Museum Collections

Climate change and landscape alterations may influence biodiversity by shifting species distributions or causing local extirpations. Museum records are needed in order to track these changes over long periods of time. Bees are a group of organisms known to be in global decline, but tracking regional shifts is difficult. In Illinois, where there have been significant alterations to the landscape, no bee species checklist is available to compare recent collecting efforts. We used museum specimens from Illinois housed at the Illinois Natural History Survey (INHS) at the University of Illinois at Urbana-Champaign, augmented by specimen records from other museums, to investigate the use of museum collections to identify species occurrences and possible declines. The result is a preliminary state checklist of 491 species of bee, with an additional 51 records considered either doubtful or possible but needing confirmation. We report 74 confirmed new state records compared to records housed at INHS, with five additional species considered doubtful and four possible but needing confirmation. Three putatively undescribed species include two Andrena species and one Lasioglossum (Dialictus) species, although further verification is needed to resolve their status. Continued support for natural history collections and the institutions that maintain them is essential for further research on the impacts to ecosystems caused by human and natural influences and to identify areas and species in need of conservation.

A new species of the Oriental leafhopper genus Kutara Distant (Hemiptera: Cicadellidae: Deltocephalinae) from Vietnam

The Oriental leafhopper genus Kutara Distant, 1908 (Cicadellidae: Deltocephalinae: Drabescini: Paraboloponina) is newly recorded from Vietnam with description of a new species K. trispinosa Xu Zhang sp. nov.. An updated checklist, with distribution and a key to males of Kutara, are also provided. The type specimens of the new species are deposited in the Muséum National d'Histoire Naturelle, Paris, France (MNHN) and the Illinois Natural History Survey, University of Illinois, Champaign, Illinois, USA (INHS).

The Prairie Chicken in Illinois

The present report summarizes a study of the biology and management of the greater prairie chicken in Illinois, a study begun in 1935 by members of the Section of Game Research and Management of the Illinois Natural History Survey. The summers of 1935 and 1936 were spent in full-time field work in southeastern Illinois. Since that time, supplemental studies of prairie chicken habits, requirements and distribution have been continued in various parts of the state. Annuallysince 1935, spring and fall censuses have been made on 4 square miles of prairie chicken range in Jasper County used as a study area. The present report includes data on earlv distribution, present range, life history, populations, mortality causes, food habits and management of the prairie chicken in Illinois.

TaxonWorks: An experience of migrating large datasets into the new cybertaxonomic infrastructure

TaxonWorks (http://taxonworks.org) in an integrated, open-source, cybertaxonomic web application serving taxonomists and biodiversity scientists. It is designed to facilitate efficient data capture, storage, manipulation, and retrieval. It integrates a wide variety of data types used by biodiversity scientists, including, but not limited to, taxonomy (with validation based on codes of zoological, botanical, bacterial, and viral nomenclature), specimen data, bibliographies, media (images, PDFs, sounds, videos), morphology (character/trait matrices), distribution, biological associations. Available TaxonWorks web interfaces currently provide various data entry forms for simple and advanced querying of the database. TaxonWorks has integrated batch uploader functionality. But, for larger datasets, specialized migration scripts were used. Several projects, historically build in 3i (http://dmitriev.speciesfile.org), MX (http://mx.phenomix.org), SpeciesFiles (http://software.speciesfile.org), and other databases, have been or are being migrated into TaxonWorks. Of the projects moving into TaxonWorks, it is worth mentioning several: 3i World Auchenorrhyncha Database, LepIndex, Universal Chalcidoidea Database, Orthoptera SpeciesFile, Plecoptera SpeciesFile, Illinois Natural History Survey Insect Collection database, and several others. An experience of the data migration will be shared during the presentation.

Females of southeastern United States species of Brachycentrus Curtis, 1984 (Trichoptera: Brachycentridae)

From 10 species of Brachycentrus Curtis, 1834 known from the southeastern United States, female genitalia of only five have been described so far. Herein, for the first time, we describe female genitalia of the following Brachycentrus species: B. appalachia Flint, 1984, B. chelatus Ross, 1947, B. lunatus Harrington and Morse, 2004, B. solomoni Flint, 1984 and B. spinae Ross, 1948. Female genitalia of B. etowahensis Wallace, 1971 are re-described. These were prepared from specimens of the Clemson University Arthropod Collection, Illinois Natural History Survey, US National Museum of Natural History, and from specimens collected in two streams in North Carolina. Based on characters of the female genitalia, a dichotomous key to all 10 southeastern US Brachycentrus species is included. Diagnostic characters are noted in the ventral and lateral shapes of fused abdominal segments IX/X, lobes of abdominal sternite VIII, and spermathecal sclerite.

Over 50 years of fish community monitoring in Illinois’ large rivers: The evolution of methods used by the Illinois Natural History Survey’s Long-term Survey and Assessment of Large-River Fishes in Illinois

This document describes the methodological evolution of the Long-Term Illinois Rivers Fish Population Monitoring Program since its inception. The principal changes include a shift from fixed-site sampling to stratified random sampling at the reach scale to benefit statistical robustness and a concurrent shift from AC electrofishing to pulsed-DC electrofishing to increase the breadth of the diversity and size classes of fishes encountered. These changes in methodology were implemented during the 2016 field season and are based on quantitative assessments of program data and other results from recent peer-reviewed publications. These refinements will likely improve the program’s ability to detect and describe patterns and trends in the fish assemblages of the Illinois River and other large rivers of Illinois and the Midwest.

Stop that. It’s degrading!

Swapping stoppers When Thomas McElrath took over as insect collection manager at the Illinois Natural History Survey (INHS) in 2017, he inherited one heck of a meltdown. Synthetic rubber stoppers t...

Wet collections accession: a workflow based on a large stonefly (Insecta, Plecoptera) donation.

This study details a workflow used to accession a large stonefly (Plecoptera) collection resulting from several donations. The eastern North American material of Kenneth W. Stewart (deceased, University of North Texas), the entire collection of Stanley W. Szczytko (deceased, University of Wisconsin, Stevens Point), and a small portion of the Barry C. Poulton collection (active, United States Geological Survey, Columbia, Missouri) were donated to the Illinois Natural History Survey in 2013. These 5,767 vials of specimens were processed to help preserve the specimen legacy of these world renowned Plecoptera researchers. The workflow used an industrialized approach to organize the specimens taxonomically, image the specimens and labels, and place the specimens into new storage. Utilizing the images as a verbatim data source, we transcribed labels in iterative steps that yielded more information with each pass. The data were normalized, locations georeferenced, all specimen data formatted to meet Darwin Core Archive format for occurrence data, and a data set created using Pensoft's Integrated Publishing Toolkit. This is the first time that any of the specimen data has been made available electronically. We also provide two important electronic supplements that include the Bill P. Stark (active, Mississippi College) Oklahoma field notebook for 1971 and 1972 detailing locations for many coded stonefly specimens in the Stewart collection, and the coded locations of B. C. Poulton's Arkansas and Missouri study. Again, we have linked coded labels in vials to normalized and georefenced site data. We confirmed 243 stonefly species were contained within the collections, and the potential for many more species exists among the specimens identified to family and genus level. Twenty-one new state, province, and other significant stonefly records are reported herein with all identifications verified by the senior author, often through consultation with other stonefly taxonomists. Researchers are encouraged to utilize the specimen data, form collaborations with the authors, and borrow specimens for research.