Location: Systematic Entomology Laboratory
2016 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
ARS researchers at Beltsville, Maryland, in collaboration with researchers in Animal Plant Health Inspection Service (APHIS) in Edinburg, Texas and the Queensland Museum in Australia are working on the identification of the mites associated with the nuclear leprosies citrus virus. The major mite species affecting the citrus production in the Americas is Brevipalpus yothersi Baker, which is associated with the Cytoplasmatic Leprosis Virus. The second species complex is in the Brevipalpus californicus group and one of the species was identified as associated with the Nuclear Leprosies Virus.
ARS researchers at Beltsville, Maryland, upgraded the web-based key (Lucid key) for the flat mites of the world. The flat mite lucid key has had thousands of visits from more than 180 countries. We were able to collect and obtain Brevipalpus and Tenuipalpus specimens from Australia, Asia, Brazil, Central America, Mexico and the U.S. A major paper on Brevipalpus californicus complex is been prepare addressing the most important species associated with viruses on citrus. Several articles on plant feeding mites, soil mites, predator mites and mite morphology were published or are under review by refereed journals.
Continued research has been accomplished on mites in the genus Daidalotarsonemus, Excelsotarsonemus, Tenuipalpus and Brevipalpus 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) and prostigmatid mites (families Pygmephoridae, Tarsonemidae, Bdellidae, Tetranychidae and Eriophyidae) were accomplished.
Accomplishments
1. Systematic studies of plant feeding mites in the family of Tenuipalpidae. This study led clarification of the mites that spread Cytoplasmatic and Nuclear leprosis citrus viruses. ARS researchers in Beltsville, Maryland, have been studying mites in the genus Brevipalpus which reveled a complex of eight species. Extensive observations and measurements of mites collected from Mexico, Australia, Costa Rica and U.S. were studied using differential contract light microscopy and low temperature scanning electron microscopy, which allowed the researchers to define characteristic structures and patterns for the correct identification of the Brevipalpus californicus group. This information was disseminated by a published monograph describing the various species and an on-line web page which has thousands of visits to the web site 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 and insect identification services. The Communications & Taxonomic Services Unit provides support with identifications and information on important mite and insect invasive and adventive species to APHIS, the State Department, and universities within the United States. In 2016 the mite section identified 431 lots with 2224 mite specimens. The Communications & Taxonomic Services Unit for FY 2016 identified 10,421 lots with 19,904 insect specimens.
Review Publications
Hernanes, F.A., Mironov, S.V., Bauchan, G.R., Ochoa, R. 2016. A new asymmetrical feather mite of the genus MIchaelia Trouessart, 1884 (Astigmata: Freyanidae) from the neotropical cormorant, Phalacrocorax brasilianus (Pelecaniformes). Acarologia. 56(1):45-61.
Roy, A., Hartung, J.S., Schneider, W.L., Shao, J.Y., Leon, G.M., Melzer, M.J., Beard, J.J., Otero-Colina, G., Bauchan, G.R., Ochoa, R., Brlansky, R.H. 2015. Role bending: complex relationships between viruses, hosts and vectors related to citrus leprosis, an emerging disease. Phytopathology. DOI: 10.1094/PHYTO-12-14-0375-FI.
Rezende, J.M., Lofego, A.C., Ochoa, R. 2015. Two new species of Daidalotarsonemus (Acari: Prostigmata: Tarsonemidae) from Brazil. Acarologia. 55(4):435-448.
Rezende, J.M., Ochoa, R., Lofego, A.C. 2015. Ten new species of Daidalotarsonemus (Prostigmata: Tarsonemidae) from Costa Rica. International Journal of Acarology. 41(6):446-493.
Castro, E.B., Kane, E.C., Feres, R.F., Ochoa, R., Bauchan, G.R. 2016. Definition of Tenuipalpus sensu stricto (Acari, Tenuipalpidae), with redescription of Tenuipalpus caudatus (Dugès) and description of a new species from Costa Rica. International Journal of Acarology. 42:106-126.
Castro, E.B., Feres, R.F., Ochoa, R., Bauchan, G.R. 2016. Tenuipalpus sensu stricto (Acari: Tenuipalpidae) from Brazil, with ontogeny and a key to the known species. Zootaxa. 4088(3):355-378.
