8th Symposium of the EURopean
Association of ACarologists

Plenary Lectures



The following international acarologists have been selected to deliver Plenary Lectures at the 8th Symposium of EURAAC.


Dr. Ronald Ochoa is Research Entomologist (Acarologist) at USDA, ARS, BA, PSI Systematic Entomology Laboratory, Beltsville, USA. He is author of m ore than 160 papers, on systematics and ecology of phytophagous prostigmatid mites (Tetranychoidea, Tarsonemoidea, Eriophyoidea) and astigmatid mites (Acaridae), biological control with predator mites (Phytoseiidae) and fungus, and general studies on integrated mite control. He has published 8 books and book chapters on plant feeding mites and has worked on the use of new low temperature scanning electron microscope (LT-SEM) techniques for the study and understanding of mite morphology.


Low Temperature SEM: an ACARI window

Ronald Ochoa 1 , Jennifer J. Beard 2 , C. Welbourn 3 , John Hammond 4 , Gabriel Otero-Colina 5 , Chris Pooley 6 and Gary R. Bauchan 6

1. USDA, ARS, Systematic Entomology Lab, BARC-West, 10300 Baltimore Ave, Beltsville, MD, 20705, USA. 2. Queensland Museum, PO Box 3300, South Brisbane, Queensland, 4101, Australia. 3. Division of Plant Industry, Florida Dept. Agriculture & Consumer Services, Gainesville, FL, 32614, USA. 4. USDA, ARS, NA, Florist and Nursery Plants Research Unit, 10300 Baltimore Ave, Beltsville, MD, 20705, US A. 5. Colegio de Postgraduado, Montecillo, Km 36.5 Carretera Mexico-Texcoco. Montecillo, Texcoco, 56230, México . 6. USDA, ARS, Electron & Confocal Microscopy Unit, 10300 Baltimore Ave, Beltsville, MD, 20705, USA

Nearly 60,000 mite species have been described thus far but the entire life cycles of only a few have been studied. Their feeding habits are just as varied, including species that are parasitic, predatory, mycophagous, saprofagous, and phytophagous. Some mites are associated with viruses and fungi and cause diseases of animals and plants. Plant-feeding mites are known to infest nearly all species of plants, including economically significant crops, timber, and ornamental plants, and cause losses to national and/or international food and fiber markets. Many animals (including insects) have mites that are phoretic, parasitic or associated with their nesting. All species of domesticated animals, and all humans, are hosts of parasitic mites.

Electron microscopy is a tool to observe external and internal structures of plants, animals and materials at resolutions and magnifications that far exceed light microscopy. In addition, structures can be photographed with greater depth of field and in stereo, revealing their true three-dimensional structures. The observation of minute specimens, such as mites, often requires the development of new procedures for specific sample preparation. Furthermore, it is usually necessary to prepare digital images of specimens for purposes of publication, and these often require the use of complex imaging and colorization technologies and techniques that are not available to most research units.

Studying the structure and the interaction of pathogens/pests, with their hosts using low temperature scanning electron microscopy (LT-SEM) provides valuable information key to understanding mite behavior and for developing management or control strategies for these pests. The ability to identify and understand animal and plant mite pest associations is critical to making decisions aimed at preventing the introduction and/or controlling the spread of newly introduced mites. Instantaneous immobilization of mites and insects using super-cooled brass bars submerged in liquid nitrogen (-196 o C) allows specimens to be studied in-situ on host materials in their natural state. Thus, such intimate observation of the interactions between insect pests, mites, animal and human parasites, fungi, bacteria and virus particles, and their hosts, provides a unique insight into the biology of these interactions.

This presentation addresses the use of LT-SEM to better understand the variation in external structures in animal and plant mites, and to collect biological and ecological data. New morphological characters have been discovered using LT-SEM that have enabled us to better characterize important economic species, distinguish cryptic species, and correlate taxonomic and molecular data on these species. This technique is helping researchers discover and understand morphological variation from a mite's point-of-view, and has ultimately provided us with a view into their microscopic world.


Dr. Marie-Stéphane Tixier is full professor in Montpellier SupAgro (Agriculture University: https://www.supagro.fr/ ), France at the UMR CBGP ( http://www6.montpellier.inra.fr/cbgp ) since 2000. She performs her research on Systematics of Phytoseiidae mites with applied focus on biological control strategies. She is involved in various national and international projects. She is author of 76 publications and a web site on E-taxonomy of Phytoseiidae mites, containing various polytomic identification tools ( http://www1.montpellier.inra.fr/CBGP/phytoseiidae/index.html ). She is teaching Plant Protection and systematics at L3, master and PhD levels. Since 2014, she is the head of the department of Biology & Ecology of Montpellier SupAgro, proposing formations in Plant Protection, Plant Breeding and Ecology.

Mite Systematics: research and education challenges for the future

M.-S. Tixier

Systematics is the basal Science that secures all the other biological Sciences and applications in Agriculture, Health and Environment. New approaches and methods combined with traditional ones have lead to important advances in phylogeny and evolution, biodiversity discovery, diagnostic implementation, big data management and in associated applied fields as biological control, biodiversity management, risk previsions under global changes. The presentation will draw a state of such advances, dress some future research challenges and will question the future of Acari Systematics considering education of students, systematics attractiveness, student grants and perennial positions in our European institutions.



Dr. Lee Goff, Professor Emeritus in Entomology and Forensic Sciences at Chaminade University of Hawaii, is one of the most highly regarded forensic entomologists, well known by his studies on insects and mites on the remains of victims, on suspects, and at crime scenes. He has also been a member of the instructional staff for the FBI Academy course in Detection and Recovery of Human Remains and served as a consultant for the television crime dramas CSI and Bones. He has been involved as curator of a traveling museum exhibition called CSI: Crime Scene Insects. He has published over 200 papers in scientific journals, authored the popular book “A Fly for the Prosecution”, co-edited “Advances in Forensic Entomology” and participated in over 350 homicide investigations, consulting on cases worldwide.

Acarine C.S.I.: The Show, The legal System and The Mites

Lee Goff

The television series “CSI Las Vegas” premiered in October 2000 and was an unexpected hit series, running for 15 complete seasons with a shortened 16th season. Unlike most crime series in the United States, it was set primarily in a crime laboratory in Las Vegas, featured a forensic entomologist/acarologist as a lead character and focused on forensic examinations of evidence rather than frantic police pursuits and gunfire. Basically, most executives were not planning much past the pilot. Instead the series continued and spawned 3 additional shows: “CSI New York, CSI Miami and CSI Cyber.” For the first 2 seasons, many of the plots were based on actual cases from Hawaii as detailed in the book “A Fly for the Prosecution.” Suddenly the general population was exposed to the forensic sciences and became interested to the extent that juries began to anticipate that forensic evidence and tests would be present in all cases, much to the dismay of the legal community on both sides. This resulted in what became known as the “CSI Effect” and has not been limited to the United States. In this presentation, the process of adapting cases originally from Hawaii to the deserts surrounding Las Vegas will be discussed, comparing actual case materials and resolutions with final TV plots. Cases to be presented involved insects and an assortment of mites ranging from soil dwelling taxa, to ticks and chiggers. The implications of the “CSI Effect” to the United States legal system will be presented along with examples of problems and concerns.