Location: Systematic Entomology Laboratory
2021 Annual Report
Objectives
Objective 1: Develop new and improve existing classifications of agriculturally important beetles based on next-generation sequencing (e.g., in cooperation with the Ag100Pests Initiative), comparative morphological and bioinformatics analyses, and modern illustration methods. [NP304, C1, PS1A; C2, PS2B; C3, PS3A and 3B; C4 PS4A and 4B – Appendix 1]
Sub-objective 1.A: Phylogenomic estimate of the leaf beetle (Coleoptera: Chrysomelidae) phylogeny with particular emphasis on flea beetles (Chrysomelidae: Galerucinae: Alticini).
Sub-objective 1.B: Infer the first phylogenomic hypothesis and revise the generic-level classification of Cossoninae (Coleoptera: Curculionidae).
Objective 2: Generate morphological and molecular diagnostic tools that will allow stakeholders and beneficiaries (e.g. Animal and Plant Health Inspection Service, Department of Homeland Security, state departments of agriculture, foreign and domestic biological control laboratories, researchers, and citizens worldwide) to accurately identify and rank agriculturally important beetles. [NP304, C1, PS1A; C2, PS2B; C3, PS3A; C4 PS4A and 4B]
Sub-objective 2.A: Interactive guide for flea beetle genera of the West Indies.
Sub-objective 2.B: Generic reassessment and Illustrated key to Nearctic Baridinae.
Objective 3: Curate and expand the U. S. National Beetle Collection to support morphological and molecular research by U.S. scientists and stakeholders worldwide and enhance pest insect diagnostics. [NP304, C3, PS3A; C2, PS2B; C3, PS3A; C4 PS4A and 4B]
Sub-objective 3.A: Curation of the National Leaf Beetle collection.
Sub-objective 3.B: Curation of the National Curculionoidea Collection.
Objective 4: Provide identifications of beetles, including plant-feeders, wood-borers, and others of agricultural, economic and environmental importance. [NP304, C3, PS3A; C2, PS2B; C3, PS3A; C4 PS4A and 4B]
Approach
To achieve objectives outlined in the plan, beetle taxon sampling will be centered around testing each hypothesis, while making every attempt to include multiple representatives of each rank to recognize the potential phylogenetic effects of contamination and systematic biases. For Chrysomelidae, the largest and most geographically inclusive taxon sample of about 600 genera across all major groups will be assembled. Cossonines from all over the world, including from recent expeditions have been accumulated. For both beetle groups field expeditions to collect missing taxa are planned to Africa, Australia, Central and South America. Variety of techniques and methods will be used for estimating phylogenies: Qiagen DNeasy Blood and Tissue Kit for DNA extraction; PHYLUCE pipeline to increase the success of hybrid capture experiments; PartitionFinder v2 - to determine the best-fit models of evolution and partition scheme according to the Bayesian Information Criterion, ASTRAL-III v5.1.1 with the set of ML gene trees, will be used to estimate the species phylogenies and, finally, as each of our hypotheses is largely taxonomic in scope; we will use our molecular data and estimated gene and species phylogenies to statistically test proposed molecular hypotheses against all other phylogenetic hypotheses that have been published for each focal lineage using the gene genealogical interrogation test (GGI). Taxon sampling for revisionary objectives of the plan are based on the taxonomic literature, museum records, available databases, and include specimens housed at the National Beetle collection (USNM), museum holdings around the world and include field work to fill the gaps in overall sample. Type species of each genus will be the focus to determine “generic level” morphological characters. Specimens will be examined for morphological features using light microscopy, scanning electron microscopy, and phase contrast compound microscopy. Finally, morphological data will be used to produce identification tools such as guides, keys, comparative descriptions, and diagnoses. Computerized, interactive identification tools on beetle taxa, developed with the assistance of computer programs such as DELTA and LucID, will be created and disseminated via the Internet. National Beetle collection is maintained and enhanced in accordance with the USNM Collections Management Procedures through field work, donated collections and specimens kept from identifications, which are mounted, labelled or otherwise processed, accessioned, databased, and incorporated into the main collection, both “dry” and DNA grade. Identification of beetles submitted by APHIS-PPQ, research and regulatory organizations in the U.S. and abroad is performed using variety of tools available at the USNM, main of which is the National Beetle collection. Identifications are reported using the SEL Identification System (SELIS) and APHIS-PPQ ARM on a daily basis as specimens are intercepted and identified. The information is tracked for decades, which provides critical data for taxonomic research programs in areas such as predictive distribution models for invasive species.
Progress Report
Progress was made in objectives, which fall under National Program 304, Component 1, Systematics and Identification, Problem Statement 1A, Insects and Mites.
In regard to Objective 1, ARS researchers in Washington, D.C., (Smithsonian Institution) completed half the DNA extractions for the leaf beetles. Furthermore, DNA grade beetle tissues were collected and solicited to improve the taxonomic scope of each sub-objective. Important taxa included in the molecular sample were identified, including genera collected in Bolivia in 2013 and material received from the California Department of Food and Agriculture that was collected in Africa and Madagascar. In addition to the progress made in the molecular laboratory, ARS researchers were successful in obtaining a grant funded by the USDA-ARS Partnership Potato Program. The grant will fund both a genome and population genomic study of a vector of the Potato leafroll virus. The data and bioinformatic tools developed as part of this grant will improve Objective 1 subsequent studies that address prevention and control of non-native agriculturally important beetle species using genomic data.
Significant progress was made in Objective 2. West Indian flea beetle was substantially revised. New genera and species inhabiting moss cushions in the West Indies were described and illustrated. Overall, flea beetle classification was improved by synonymizing seven genera, which species were misplaced by researchers over the past 20 years. An updated catalog of flea beetles of the entire Palearctic biogeographic region was prepared for publication. Dates of publication of species described in the 19th century were corrected based on newly discovered bibliographies. Databases for Cossoninae (Taxonworks) and Baridinae (Mantis/Taxonworks) have been initiated. A preliminary atlas of cossonine and Nearctic genera is in the works with several collaborators. Baridine Genbank sequences are being analyzed to infer relationships. A morphological character study and matrix is underway for both cossonines and Nearctic baridines; initially focusing on external characters due to constraints (access to the collection). A new anophthalmous psammophilous species from Madagascar of the Australian cossonines genus Halorhynchus is being described, and a synopsis and the first illustrated key to cossonine tribes of the World is in preparation. I was invited to collaborate on a study of cossonine weevils of Palmyra.
Objective 3 did not see much progress as the museum was substantially closed, which prohibited major curation activity. However, the DNA grade collection of leaf beetles grew by about 200 records. About 3000 leaf beetle specimens collected over the years in Europe and Asia were mounted, labeled , and partially sorted into genera and species.
For Objective 4, which falls under National Program 304; Component 3, Insects and Mites; Subcomponent 3B, Natural Ecosystems; Problem Statement 3B1, Early detection and prevention of both invasive and native insect and mite pests. ARS researchers in Beltsville, Maryland, (Smithsonian Institution) completed identification of beetles, including those intercepted at all ports-of-entry into the U.S., and those submitted to the laboratory by universities and agricultural extension agencies entered the data in the Systematic Entomology Laboratory Identification System. Large numbers of beetle identifications have been made. In the period from September 30, 2020 to October 1, 2021, 7,154 submitted lots containing 15,199 specimens were identified, including thousands “urgent”, “prompt”, and “rush” submittals for USDA-APHIS-PPQ of specimens intercepted on perishable commodities in the U.S. ports of entry. “Urgent” identifications (those requiring same-day turn-around of specimens intercepted on perishable commodities at ports of entry) have been processed daily as submitted. In addition, ARS researchers submitted a USDA-ARS Innovation Grant to develop an artificial intelligence tool to identify non-native agriculturally important leaf beetles. Specifically, the grant addresses the need for such a tool by focusing on the leaf beetle genus Epitrix, which contains quarantine species that threaten many U.S. agricultural commodities such as potatoes, tomatoes, bell peppers, and eggplants.
Accomplishments
1. Cossonine weevil resources. Developed and oversees a faunal digitization project and publication of an annotated catalog to the weevils of the Hawaiian Islands. Hawaii is home to several rare and endemic cossonine weevils. These resources aim to provide comprehensive identification baseline data for all 450 native and non-native weevil species of the Hawaiian Archipelago. This combined digital aggregator and print catalog is the single source of data currently available to determine potential invasive species in the South Pacific and is invaluable to State, Federal, Private, and University collaborators. This resource assists with conservation management efforts to protect and monitor the vulnerable local weevil fauna, especially endemic bark beetles and cossonines, while attempting to control and manage the invasive Coffee Berry Borer and other invasive species in Hawaii.
2. Discovering, documenting, and classifying pestiferous flea beetles. The flea beetles are plant feeders that belong to a hyper-diverse group of about 9,900 species, many of which are serious pests and feed on crops destroying valuable plants costing U.S. economy millions of dollars annually. ARS researchers in Washington, D.C., in collaboration with researchers in Brazil, India, and the Netherlands, studied historical beetle collections in Europe and North America and conducted field investigations in Brazil, India, and the West Indies. The subsequent in-depth examination of obtained beetle specimens resulted in significant changes in flea beetle classification. New classification combines species previously considered unrelated and belonging to distant generic groups under fewer generic names. Beetles previously unknown to science have been properly described, documented, and illustrated. They are incorporated into an improved classification, making it more inclusive, logical, anduser-friendly and assures easy access to the information on beetle relationships and other biological traits. Improved classification will be an important tool for agricultural scientists, practitioners, biological control researchers, and anybody interested in plant-feeding beetles.
Review Publications
Giron, J.C., Chamorro, M.L. 2020. Variability and distribution of the golden-headed weevil Compsus auricephalus (Say) (Curculionidae: Entiminae: Eustylini). Biodiversity Data Journal. 8(e55454):1-50.
Florio, J., Veru, L., Dao, A., Yaro, S.A., Diallo, M., Sonogo, L.Z., Djibril, S., Huestis, D., Ousman, Y., Talamas, E.T., Chamorro, M.L., Frank, H., Biondi, M., Bartlett, C., Strobach, U., Linton, Y., Chapman, E., Reynolds, D., Fairman, R., Krajacich, B., Weetman, D., Donnelly, M., Lehmann, T. 2020. Massive windborne migration of Sahelian insects: diversity, seasonality, altitude, and direction. Ecography. 10(20523):1-14. https://doi.org/10.1038/s41598-020-77196-7.
Chamorro, M.L., De Medeiros, B., Farrell, B.D. 2021. First phylogenetic analysis of Dryophthorinae (Coleoptera, Curculionidae) based on structural alignment of ribosomal DNA reveals Cenozoic diversification. Ecology and Evolution. 11(5):1984-1998. https://doi.org/10.1002/ece3.7131.
Chamorro, M.L. 2020. Death of a tribe: transfer of Onychius Chapuis to Rhyncolini Gistel and synonymy of Onychiini Chapuis with Rhyncolini (Coleoptera, Curculionidae, Cossoninae). Proceedings of the Entomological Society of Washington. 122(3):750-756. https://doi.org/10.4289/0013-8797.122.3.750.
Konstantinov, A.S. 2021. Flea beetles of the West Indies: new combinations and new species (Coleoptera: Chrysomelidae: Galerucinae: Alticini). Journal of Insect Biodiversity. 25(1):1-27. https://doi.org/10.12976/jib/2021.25.1.1.
Sokolov, I.M. 2021. A new subterranean species of Anillinus Casey (Carabidae, Trechinae, Anillini) from Florida. Subterranean Biology. 39:33-44. https://doi.org/10.3897/subtbiol.39.65769.
Konstantinov, A.S. 2021. Flea beetles of the West Indies: genus Hemilactica Blake, 1937 (Coleoptera: Chrysomelidae: Galerucinae: Alticini). ZooKeys. 1044:589-607. https://doi.org/10.3897/zookeys.1044.62632.
