Location: Systematic Entomology Laboratory
2017 Annual Report
Objectives
Objective 1: Develop accurate species concepts within the Tenuipalpidae (flat mites) using a holistic approach based on morphological and ecological data. Objective 2: Develop accurate species concepts within the Tarsonemidae (white mites) through discovery of new characters for species separation and subsequent systematic relationships. Objective 3: Coordinate the process of incoming and outgoing arthropod specimens and identifications, and maintain SELIS (Systematic Entomology Laboratory Identification Service), the on-line identification database on agriculturally important arthropods, for use in quarantine, conservation, pest management, and other ARS research programs.
Approach
Morphological characters will be identified through the examination of specimens (~2500 slides) located at the National Mite Collection and specimens collected from the Americas, Australia and China. Observation of the specimens will use dissecting, Differential Interference Contrast (DIC), Phase Contrast, Confocal Laser Scanning Microscopy (CLSM), Variable Pressure Scanning Electron Microscopy (VP-SEM), and Low Temperature Scanning Electron Microscopy (LT-SEM). Recognized morphological characters of several mite genera in the families Tarsonemidae and Tenuipalpidae will be identified, quantified, and used to develop hypotheses of phylogenetic relationships among higher level taxa. The characters will be evaluated using modern phylogenetic programs. The resulting phylogenies will be used to develop natural, robust classifications of higher level taxa among and within these four families.
Progress Report
300+ specimens of Brevipalpus have had DNA extracted. DNA sequences have been compared with other Brevipalpus spp. sequences to help determine species. This initial work has resulted in determining a complex of species in the Brevipalpus californicus Group. This will help the confusion in this important economic plant feeding mite group and points to the correct species vector of nuclear leprosis virus.
Continued research has been accomplished on mites in the genus Tenuipalpus, Raoiella and Brevipalpus (ACARI: Tenuipalpidae) intercepted at ports-of-entry or mites important in plant protection programs. Scanning electron micrograph images and keys for some important tenuipalpid mites (including species in the genus Brevipalpus, Tenuipalpus, Colopalpus and Raoiella) were accomplished.
Continued research has been accomplished on mites in the genus Tarsonemus excelsotarsonemus, Daidalotarsonemus, and Ceratotarsonemus (ACARI: Tarsonemidae) intercepted at ports-of-entry or mites important in plant protection programs. Scanning electron micrograph images and keys for some important tarsonemid mites (including species in the genus Tarsonemus excelsotarsonemus, Daidalotarsonemus, and Ceratotarsonemus were accomplished.
Continued research has been accomplished on prostigmatid mites (families Tuckerellidae, Eriophyidae and Tetranychidae).
Made 304 urgent identifications of ACARI as of 20 June 2017; 15 routine/prompt identifications with 117 specimens of ACARI as of 20 June 2017.
Accomplishments
1. Plant-feeding mites of agricultural importance. Studies on mite species (Brevipalpus) that spread Cytoplasmatic and Nuclear leprosis citrus viruses have been done. ARS scientists at Beltsville, Maryland, in collaboration with researchers in Animal Plant Health Inspection Service (APHIS) in Florida, California and Texas, and the Queensland Museum in Australia are working in the identification of the mites that feed on citrus. Extensive observations and measurements of mites collected worldwide were studied using scanning electron microscopy, which allowed the researchers to define characteristic structures and patterns for the correct identification of the citrus mites. This information has been published in a monograph online describing the various species. The web page has over a thousand visits with inquiries from more than 180 countries. This research will be used by researchers, citrus growers, and border inspection agents to safeguard our country from invasive, destructive diseases.
2. Mite identification on the Web. Bees play a crucial role in U.S. agriculture as pollinators of many important crops. In-depth studies of bee mites in several families have been accomplished. Bee collaborative research with the University of Michigan and USDA-APHIS designed an interactive web based identification tool to identify mites that may be found on bees and in their nests and distinguish harmless mites from those that might harm bees or their colonies. The searchable image gallery contains over 850 mite images making it possible to compare images from multiple types of mites. This web site covers bee-associated mite genera from around the world, with an emphasis on those associated with important pollinators, including honey bees, mason bees, and bumble bees in temperate regions, and stingless bees and large carpenter bees in the tropics. This interactive key is useful to bee keepers, scientists, extension agents, and quarantine officers worldwide.
Review Publications
Chetverikov, P.E., Amrine, J., Bauchan, G.R., Ochoa, R., Sujhareva, S.I., Vishnyakov, A.E. 2017. Supplementary description of Novophytoptus stipae Keifer 1962 (Acariformes, Eriophyoidea) with LT-SEM observation on mites from putatively conspecific populations: cryptic speciation or polyphagy. Systematic and Applied Acarology. 22(2):253-270.
Welbourn, W.C., Beard, J.J., Bauchan, G.R., Ochoa, R. 2016. Description of two species of Tenuipalpus (Acari: Trombidiformes) from succulent plants. International Journal of Acarology. 4088(3):355-378.
Castro, E.B., Ramos, F.M., Feres, R.F., Ochoa, R., Bauchan, G.R. 2017. Redescription of Tenuipalpus heveae Baker (Acari: Tenuipalpidae) and description of a new species collected on rubber tree from Amazonia, Brazil. Acarologia. 57(2):421-458.
