Alexey Polilov

Alexey Polilov
Lomonosov Moscow State University | MSU · Department of Entomology

PhD, Dr. Sc., Prof. and Corr. Member RAS
Microinsects researcher

About

133
Publications
24,478
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,048
Citations
Introduction
The main direction of my work is сomprehensive study of the smallest insects and other arthropods
Additional affiliations
May 2011 - November 2014
Lomonosov Moscow State University
Position
  • Professor (Associate)
April 2011 - November 2014
Lomonosov Moscow State University
Position
  • Professor (Associate)
January 2006 - April 2011
Lomonosov Moscow State University
Position
  • Reseacher
Education
October 2003 - December 2006
Lomonosov Moscow State University
Field of study
  • Entomology
September 1998 - May 2003
Lomonosov Moscow State University
Field of study
  • Zoology, Entomology

Publications

Publications (133)
Article
Miniaturization leads to considerable reorganization of structures in insects, affecting almost all organs and tissues. In the smallest insects, comparable in size to unicellular organisms, modifications arise not only at the level of organs, but also at the cellular level. Miniaturization is accompanied by allometric changes in many organ systems....
Book
This book addresses microinsects, their structure and their differences from larger relatives. Moreover, it discusses structural changes that accompany extreme diminution in living organisms, evolutionary inventions that help insects to live in the microworld, and factors that limit the size of animals. It also takes a careful look at the potential...
Article
Full-text available
Size is a key to locomotion. In insects, miniaturization leads to fundamental changes in wing structure and kinematics, making the study of flight in the smallest species important for basic biology and physics, and, potentially, for applied disciplines. However, the flight efficiency of miniature insects has never been studied, and their speed and...
Article
Full-text available
Flight speed is positively correlated with body size in animals ¹ . However, miniature featherwing beetles can fly at speeds and accelerations of insects three times their size ² . Here we show that this performance results from a reduced wing mass and a previously unknown type of wing-motion cycle. Our experiment combines three-dimensional reconst...
Article
Megaphragma species are important models for basic organismal research, and many are potential biological control agents. We present the first extensive revision of species of the genus Megaphragma based on morphological and molecular data. Our revision includes all previously described species, 6 of which are synonymized, and 22 of which are descr...
Article
Full-text available
Revision of the world species of Megaphragma Timberlake (Hymenoptera: Trchogrammatidae). 22 new species are described and a key for 32 valid species is provided.
Cover Page
Full-text available
Built for speed. The cover shows the feather-like wings of the tiny beetle Paratuposa placentis. How fast an animal can fly is usually dictated by its size: the larger the animal, the faster it flies. But at just 395 micrometres big, P. placentis bucks this trend by flying as fast as insects three times its size.
Article
Full-text available
As the study of the human brain is complicated by its sheer scale, complexity, and impracticality of invasive experiments, neuroscience research has long relied on model organisms. The brains of macaque, mouse, zebrafish, fruit fly, nematode, and others have yielded many secrets that advanced our understanding of the human brain. Here, we propose t...
Article
Full-text available
Extreme miniaturization implies a high degree of optimization, rendering the retention of non-functional organs almost impossible. Two unique non-porous placoid sensilla on the antennae of females of Megaphragma were described in the literature. Placoid sensilla in Hymenoptera have an olfactory function and always bear pores; the apparent absence o...
Preprint
Full-text available
Flight speed generally correlates positively with animal body size [1]. Surprisingly, miniature featherwing beetles can fly at speeds and accelerations of insects three times as large [2]. We show here that this performance results from a previously unknown type of wing motion. Our experiment combines three-dimensional reconstructions of morphology...
Article
Full-text available
Modern morphological and structural studies are coming to a new level by incorporating the latest methods of three-dimensional electron microscopy (3D-EM). One of the key problems for the wide usage of these methods is posed by difficulties with sample preparation, since the methods work poorly with heterogeneous (consisting of tissues different in...
Article
During metamorphosis, the insect CNS undergoes both structural and allometric changes. Due to their extreme de-embryonization and parasitism, the formation of the CNS in egg parasitoids occurs at the late larval stage. Our study provides the first data on the morphological and volumetric changes of the CNS occurring during the pupal development of...
Article
Full-text available
Revealing scaling rules is necessary for understanding the morphology, physiology and evolution of living systems. Studies of animal brains have revealed both general patterns, such as Haller's rule, and patterns specific for certain animal taxa. However, large-scale studies aimed at studying the ratio of the entire neuropil and the cell body rind...
Article
Full-text available
Miniaturization is a major evolutionary trend prominent in insects, which has resulted in the existence of insects comparable in size to some unicellular protists. The adaptation of the complex antennal multisensory systems to extreme miniaturization is a fascinating problem, which remains almost unexplored. We studied the antennal sensilla of Scyd...
Article
Miniaturization strongly affects functional morphology. Whereas some anatomical structures are barely affected by scaling, others can fundamentally change as the body becomes ever smaller. No prior study has focused on the effect of miniaturization on grooming and attachment structures in Hymenoptera, which can be highly diverse and complex. Throug...
Article
Full-text available
Most microinsects have feather-like bristled wings, a state known as ptiloptery, but featherwing beetles (family ptiliidae) are unique among winged microinsects in their ability to fold such wings. An asymmetrical wing folding pattern, found also in the phylogenetically related rove beetles (Staphylinidae), was ancestral for ptiliidae. Using scanni...
Article
Full-text available
Aerodynamic force generation capacity of the wing of a miniature beetle Paratuposa placentis is evaluated using a combined experimental and numerical approach. The wing has a peculiar shape reminiscent of a bird feather, often found in the smallest insects. Aerodynamic force coefficients are determined from a dynamically scaled force measurement ex...
Article
Acoustic communication plays an important role in the life of insects and especially in representatives of the order Orthoptera. Their vibrational signalling, unlike signalling by sound, is poorly studied. The pygmy grasshoppers Tetrix tenuicornis (Sahlberg, 1891) belonging to the ancestral family Tetrigidae (Orthoptera) can produce several types o...
Article
Full-text available
Body size reduction, also known as miniaturization, is an important evolutionary process that affects a number of physiological and phenotypic traits and helps animals conquer new ecological niches. However, this process is poorly understood at the molecular level. Here, we report genomic and transcriptomic features of arguably the smallest known i...
Article
Full-text available
Smaller animals display pecular characteristics related to their small body size, and miniaturization has recently been intensely studied in insects, but not in other arthropods. Collembola, or springtails, are abundant soil microarthropods and form one of the four basal groups of hexapods. Many of them are notably smaller than 1 mm long, which mak...
Data
A view of the outer chiasm and first optic neuropil of the Megaphragma amalphitanum visual system. Skeletal reconstructions of photoreceptor axons and lamina monopolar neurons corresponding to 18 optical facets (ommatidia). This tiny wasp only has 29 ommatidia in each of its compound eyes compared to the ~750 found in that of Drosophila. Neuron r...
Preprint
Full-text available
Body size reduction, also known as miniaturization, is an important evolutionary process that affects a number of physiological and phenotypic traits and helps animals to conquer new ecological niches. However, this process is poorly understood at the molecular level. Here, we report genomic and transcriptomic features of arguably the smallest know...
Article
Pterothoracic structures of the minute ptiliid Nephanes titan were examined and described in detail. Effects of miniaturization and the phylogenetic and functional background are discussed. Apomorphies shared with Hydraenidae are the large metascutal shield, the fringe of setae along the posterior edge of the wings, and the fusion of the mesoventri...
Article
The coleopteran family Ptiliidae (featherwing beetles) includes some of the smallest insects known with most of the representatives of this family measuring less than 1 mm in body length. A small body size largely determines the morphology, physiology, and biology of an organism and affects the organization of complex sense organs. Information on t...
Article
The wings of Ptiliidae, the coleopteran family containing the smallest free-living insects, are analyzed in detail for the first time. A reconstruction of the evolutionary sequence of changes associated with miniaturization is proposed. The wings of several species are described using light microscopy and scanning electron microscopy. The morpholog...
Article
The smallest beetles and the smallest non-parasitic insects belong to the staphylinoid family Ptiliidae. Their adult body length can be as small as 0.325 mm and is generally smaller than 1 mm. Here we address the phylogenetic relationships within the family using formal analyses of adult morphological characters and molecular data, and also a combi...
Cover Page
Full-text available
ScienceDirect Illustration on front cover: One of the smallest insects, the featherwing beetle Nephanes titan (Coleoptera: Ptiliidae) is shown in an eye of a needle in an SEM micrograph taken by A.A. Polilov.
Article
Full-text available
One of the major trends in the evolution of parasitoid wasps is miniaturization, which has produced the smallest known insects. Megaphragma spp. (Hymenoptera: Trichogrammatidae) are smaller than some unicellular organisms, with an adult body length of the smallest only 170 µm. Their parasitoid lifestyle depends on retention of a high level of senso...
Article
Revealing the effect of brain size on the cognitive abilities of animals is a major challenge in the study of brain evolution. Analysis of the effects of miniaturization on brain function in the smallest insects is especially important, as they are comparable in body size to some unicellular organisms and next to nothing is known about their cognit...
Article
Full-text available
Myxophaga are a small group of beetles, but phylogenetically crucial as one of the four coleopteran suborders. The monogeneric Sphaeriusidae, one of four myxophagan families, comprise about 20 species, most of them living in moist substrate at river edges. The morphology of the minute hemispherical adult is very insufficiently known. Consequently,...
Article
Full-text available
Here is the first description of the visual organ of Acrotrichis grandicollis, a member of Ptiliidae family that includes the smallest free-living insects. The apposition eyes of A. grandicollis have the acone-type crystalline cone; a fused rhabdom is formed by eight retinula cells and surrounded by primary pigment cells. Secondary pigment cells ar...
Article
Ptiliidae include the smallest known beetles. External and internal head structures of species with different body sizes and feeding preferences were examined and described in detail. Saprophagous and sporophagous species are compared. The observed features are evaluated with respect to their phylogenetic and functional significance, and their corr...
Article
Full-text available
Megaphragma is recorded for the first time in Columbia where it is represented by M. caribea that emerged from leaves of Terminalia catappa infested by the thrips (Heliothrips haemorrhoidalis and Selenothrips rubrocinctus). M. caribea has anucleate neurons, the third species of Megaphragma shown to have this feature.
Article
Full-text available
Miniaturization is an evolutionary process that is widely represented in both invertebrates and vertebrates. Miniaturization frequently affects not only the size of the organism and its constituent cells, but also changes the genome structure and functioning. The structure of the main heat shock genes (hsp70 and hsp83) was studied in one of the sma...
Article
Miniaturization is an evolutionary process that is widely represented in both invertebrates and vertebrates. Miniaturization frequently affects not only the size of the organism and its constituent cells, but also changes the genome structure and functioning. The structure of the main heat shock genes (hsp70 and hsp83) was studied in one of the sma...
Article
The third communication in this series describes the structure of the brain in one of the smallest psocopterans, Liposcelis bostrychophila (Liposcelididae), studied in a series of histological sections with the use of 3D reconstructions and TEM. Like all microinsects, L. bostrychophila shows both oligomerization and concentration of ganglia, an inc...
Article
This article describes the morphology and ultrastructure of the brain of the greenhouse thrips, Heliothrips haemorrhoidalis (Thripidae), studied in a series of histological sections with the use of 3D reconstructions and TEM. The structural peculiarities of the brain organization and its features associated with body miniaturization as well as its...
Article
The body size, especially in cases of extreme reduction, is an important characteristic that strongly determines the morphology, physiology, and biology of animals. Miniaturization is a widespread trend in animal evolution and one of the principal directions of evolution in insects. Miniaturization-related features of insect morphology have been su...
Data
Internal morphology of Megaphragma mymaripenne, 3D. (A, B) Intestine and Malpighian tubules; (C, D) Central nervous system; (A, C) Dorsal view; (B, D) Lateral view; ag–abdominal ganglion, cer–cerebrum, gg1.2.3 –pro-, meso-, and metathoracic ganglia, mg–midgut, mt–Malpighian tubules, oes–oesophagus, rc–rectum, soeg–suboesophageal ganglion. (PDF)
Data
Reproductive system of Megaphragma mymaripenne, 3D. (A, B) Female; (C, D) Male; (A, C) Lateral view; (B, D) Dorsal view; acg–acid gland, aed–aedeagus, agl–accessory glands, alg–alkaline gland, ova–ovary, spt–spermatheca, stl–stylet of ovipositor, te–testis, val–valves of ovipositor. (PDF)
Data
Supplementary references. (PDF)
Data
Interactive animated 3D reconstruction of the Megaphragma mymaripenne for Fig 5. Click on the figure to start interactive 3D view. Colors: blue–cuticle, green–digestive system, yellow–central nervous system, brown–musculature, purple–reproductive system. (PDF)
Data
Internal structure of Megaphragma mymaripenne. (A) Scheme of sections, lateral view; (B–E) Longitudinal sections, toluidine blue, pyronine; acg–acid gland, ag–abdominal ganglion, cer–cerebrum, fr2 –mesophragma, gg1,2,3 –pro-, meso-, and metathoracic ganglion, mg–midgut, mt–Malpighian tubules, oc–eye, ova–ovary, rc–rectum. Musculature see text. (PDF...
Data
Homology of head musculature in Hymenoptera. (PDF)
Data
Musculature of adult Chalcidoidea and Ichneumonoidea. (PDF)
Data
Homology of musculature of mesosoma in Hymenoptera. (PDF)
Article
Full-text available
Over millions of years of evolution, the genomes of modern insects have accumulated a significant num­ ber of mutations, which often can lead up a blind alley when carrying out phylogenetic research. Genomic differences between some representatives belonging to the same family or group are often so great that they demand using nonconventional metho...
Article
Full-text available
The vast majority of multicellular organisms coexist with bacterial symbionts that may play various roles during their life cycle. Parasitoid wasp Megaphragma amalphitanum (Hymenoptera: Trichogrammatidae) belongs to the smallest known insects whose size is comparable with some bacteria. Using 16S rRNA gene sequencing and Whole Genome Sequencing (WG...
Article
The study of the influence of body size on structure in animals, as well as scaling of organs, is one of the key areas of functional and evolutionary morphology of organisms. Most studies in this area treated mammals or birds; comparatively few studies are available on other groups of animals. Insects, because of the huge range of their body sizes...
Article
Miniaturization of organisms is one of the most interesting evolutionary phenomena. This is a very common process and is widely represented in multicellular organisms: invertebrates (nemertean, nematodes, brachiopods, mollusks, arachnids, and insects), and vertebrates (fishes, amphibians, birds, and even mammals). Miniaturization leads to a signifi...
Article
Описано строение мозга одного из мельчайших сеноедов Liposcelis bostrychophila (Liposcelididae), изученное по сериям гистологических срезов с применением трехмерного компьютерного моделирования, а также трансмиссионной электронной микроскопии. Как и у всех микронасекомых, у L. bostrychophila отмечены олигомеризация и концентрация ганглиев, увеличен...
Article
В четвертой статье цикла описаны строение и ультраструктура мозга тепличного трипса Heliothrips haemorrhoidalis из семейства Thripidae, изученные по сериям гистологических срезов с применением трехмерного компьютерного моделирования и трансмиссионной электронной микроскопии. Впервые рассмотрены строение и ультраструктурная организация мозга имаго и...
Chapter
Studies on the structure of Liposcelididae (Psocoptera) are briefly reviewed. The internal structures of adults and first instar nymphs are described in detail for Liposcelis bostrychophila (Psocoptera: Liposcelididae). It is shown that Liposcelis, in spite of its minute size, shows no strong simplification of the structure. The principal miniaturi...
Chapter
Miniaturization leads to considerable changes in the structure of insects, affecting almost all organs and tissues. The nature of such changes in different organ systems can be quite different. The smallest insects, comparable in size to unicellular organisms, display modifications not only at the level of organs, but also at the level of cells. Di...
Chapter
Insects are very convenient for studying the scaling of organs and tissues which is associated with extreme miniaturization: first, they have a huge range of body sizes (the largest is more than 2000 times as long as the smallest); second, the smallest insects are comparable in size to unicellular organisms but retain high morphological complexity....
Chapter
The history of studies on the morphology of featherwing beetles is briefly reviewed. The internal morphology of adults and larvae of Ptiliidae is described in detail. Miniaturization-related structural features are revealed; the main ones are the following: absence of muscles of midgut, absence of heart, reduction of circulatory system and its repl...
Chapter
Several methods that are widely used in insect studies are also used for microinsects, but most of them have to be adjusted and optimized for successful usage in microinsect studies. In this chapter, the collecting methods for the principal groups of microinsects are briefly reviewed, different methods of fixation and storage of material are descri...
Chapter
The history of studies of the structure of Corylophidae (Coleoptera) is briefly reviewed. The external and internal morphology of adults and larvae of corylophids are described in detail. It is shown that in spite of their minute size the structure of corylophids is not strongly simplified. The main peculiar morphological features of corylophids ar...
Chapter
Studies on the morphology of Thripidae (Thysanoptera) are briefly reviewed. The internal morphology of adults and first instar nymphs is described in detail for Heliothrips haemorrhoidalis (Thripidae). It is shown that in spite of the minute size Heliothrips is not strongly simplified in structure. The main miniaturization-related anatomical featur...
Chapter
Studies on the structure of Mymaridae (Hymenoptera) are briefly reviewed, and the external and internal morphology of mymarids are described in detail. It is shown that in spite of minute size most mymarids do not display strong simplification of structure, except for the fusion of some elements of the skeleton, minor simplification of the endoskel...
Chapter
The first introductory chapter provides a brief history of the study of miniaturization in insects and other animals and a review of available data on the size of the smallest insects and the range of sizes in various groups of animals.
Chapter
Adults and larvae or nymphs of microinsects display both similar and different miniaturization-related features. The nature of differences in such features depends above all on the type of metamorphosis and mode of life. In hemimetabolous microinsects, as in larger holometabolous insects, the body plans of adults and nymphs are almost identical, an...
Chapter
Limiting factors of decrease in body size is of considerable theoretical interest to general biology. Two hypotheses have been put forward on the structural factors that limit miniaturization in insects. The first hypothesis refers to all insects: minimum body size is limited by increasing the relative volume of the central nervous system, which, i...
Chapter
Miniaturization is a widespread evolutionary trend; miniature forms occur in many groups of animals. Morphological features related to the diminution of body size can be very different in different groups of animals and include both features shared by all animals and unique features of particular animal species. In this chapter, the consequences of...
Chapter
Studies on the morphology of Trichogrammatidae are briefly reviewed. The external and internal morphology of Trichogramma and Megaphragma are described in detail. It is shown that in spite of minute size, external structures of adult Trichogrammatidae remain complex. Such internal structures of these wasps as the intestine and tracheal and circulat...
Article
Anatomy of the adult and the first-instar nymph of Liposcelis bostrychophila (Psocoptera, Liposcelididae) is described in detail for the first time based on series of sections and 3D computer reconstruction. Despite its tiny size, no strong structural simplification is observed in Liposcelis. The main features of the anatomy of this species associa...
Article
A new set of data on the internal and external structure of the adult and larva of the thrips Heliothrips haemorrhoidalis (Bouché, 1833) is presented. The structure of the internal systems of this thrips was revealed using modern methods of 3D computer modelling. The changes in shape and relative size are discussed as an outcome of miniaturization...
Article
Anatomy of the adult fairyfly Anaphes flavipes (Hymenoptera, Mymaridae) is described in detail for the first time, based on series of sections and 3D computer reconstruction. Despite its tiny size, A. flavipes does not demonstrate strong morphological simplification, except for the merging of certain skeletal elements, a slight simplification of en...
Article
Anatomy of adults of Trichogramma evanescens (Hymenoptera: Trichogrammatidae) is described in detail for the first time based on series of sections and 3D computer reconstruction. The complex structure of the exoskeleton and musculature (except for reductions of individual muscles) is preserved in T. evanescens despite its tiny size. Considerable s...
Article
The mouthparts and musculature of the head of Sericoderus lateralis are described. It is shown that the mouthparts of minute beetles preserve their complex structure and are not significantly affected by miniaturization. Such stability allows these features to be used in macrosystematics of groups with variable body size.