Preface   I feel great pleasure to bring out this Illustrated Dictionary of Entomology for the benefit of primarily amateur entomologists, naturalists and agricultural scientists with an interest in insects and for all those who have special interest to understand the world of insects. The technical words related to the various disciplines of entomology have been included in this Dictionary and where ever possible the technical meaning of these words have been tried to make it more clear with the help of labeled illustrations. Efforts have been made by the author to define the entomological terms in a simple manner in order to make them understandable by the students of entomology and all those who are not the experts of entomology rather they encounter such technical words while dealing with the related literature and fails to understand its real meaning as the meaning provided in general English dictionaries may not give the clear picture of these technical terms. The university students of biology and agriculture sciences in the beginning face lot of problems in understanding the subject because of poor knowledge of such technical words which are also not included in the general English dictionaries. About 4016 technical terms related to the morphology, anatomy, physiology, systematics, ecology, pest management and general entomology have been defined. An individual technical word having different applications have been incorporated in a convincible manner with the help of illustrated diagram. Therefore this dictionary will serve as a ready reckoner to the students of such discipline. This dictionary will also be useful for all those who are to appear in some competitive examinations to understand and solve the objective type questions. It is believed that this dictionary will find equal favour with the teachers, students and all those who deal insects in one way or the other. Any suggestion received from any quarter would be given due consideration and may be incorporated while reprinting / revising the dictionary. The author is grateful to Dr. S. R. Singh, Director, Institute of Agricultural Sciences, Banaras Hindu University for moral support and to Professor D. S. Mishra, Head, Department of Entomology & Agril. Zoology, B. H. U. for constant encouragement, support and blessing throughout the preparation of this manuscript. In my academic pursuits I have faced tough times and it was strenuous to pass over such periods. Dr. Prabhakar Jha, Professor of French in Banaras Hindu University and Formerly Ambassador of India to Madagascar because of whose blessings I could not bother for such arduous situations. Really I am very lucky to have his blessings. Preparation of this dictionary has been a time consuming task that demanded long hours. I thank Mrs Usha Nath, my life partner for her everlasting support of my career, and especially during the years when I was surrounded by ill wills. I cannot forget her life giving moral support which gave me the strength to think and do positive. Certainly I consumed the time of my children Divya and Sanskar which they deserved to understand this complex world. I thank both of them as they bothered me not and shaped their destiny as they wished. I thank Mr. S. G. Sunderarajan, my colleague who always helped me to come out of the web of ill will designes and encouraged me to remain bussy. I cannot forget his contributions and express my heartful gratitude. I thank Mr. Virendra Nath Vishwakarma for typing the manuscript and Mr. Anand Kumar Pandey, my Ph. D. student, for help in the preparation of manuscript, his help have added greatly to the value and reliability of this work.

“Age and Area”: The hypothesis (by Willis) that the older a species is, the wider will be its geographical distribution. A-Without; lacking. A.I.: See active ingredient. A.O.U. Code: A code of nomenclature published in 1885 (revised 1908) by the American Ornithologists’ Union for the standardization of bird nomenclature. Ab-Away from; off.

Bacillus thuringiensis (Bt): Soil-inhabiting bacterium that produces an insecticide effective against larval stages of many species of Lepidoptera, although some strains are effective against various beetle, mosquito, and blackfly larvae. Backcross: A cross between a hybrid and one of its parents; a cross between a heterozygote and a homozygote (cf. Hybridization, Heterozygous, Homozygous). Bacterial insecticide: Bacteria pathogenic to insects (e.g., Bt or B. popilliae). Applied using application techniques also used for chemical pesticides. Bacterium (pl. bacteria): Microscopic, prokaryotic, single-celled organisms having cell walls but lacking membrane-bound organelles. Important in decomposition, nitrogen fixation and other symbiosis, and as pathogens. A significant component of soil food webs. Bait (B): A pesticide formulation that combines an edible or attractive substance with a small amount of toxic active ingredient (usually about 5%). Baits containing poisonous chemical and food stuffs are primarily offered to pests as food for control of animal pests like mollusks, cutworms, and rodents.

Caecae: Saclike or tubular structures open at only one end (blind), often opening from the mid-intestine (Fig. 41). Caecum (pl. caeca): A blind-ending tube or sac or pouch sac of the alimentary canal (L. caecus= blind) e.g., haepatic caecae in the alimentary canal of insects (Fig. 41). Calamistrum: One or two rows of curved spines on the metatarsus of the hind legs (spiders; fig. 608, clm). Calibration: The adujustment of application equipment so that a defined quantity of chemical or other material is applied per unit time or area. Calling: A vergin female moth releasing sex pheromones to attract males for the purpose of mating. Calliphorin: A protein produced in the fat body and stored in the haemolymph of larval Calliphoridae (Diptera).

Dall code: A code of nomenclature prepared by W.H. Dall at the direction of the American Association for the Advancement of Science (1877). Damage boundary: The level of injury where damage can be measured. Damage threshold: Pest population above which crop loss occurs. Damage: Measurable reduction in crop growth or yield; or a measurable loss of host utility, most often including yield quantity, quality, or aesthetic appeal. Damping off: Infection of newly formed roots and stems of young seedlings by fungi or bacteria, typically at soil level, resulting in decay or seedling death. Danger: A signal word used on pesticide labels to inform the user that the pesticide is highly toxic, as defined by FIFRA. The word poison and the skull and crossbones symbol always accompany the signal word danger.

Early postemergence: The application of herbicide after plant emergence and during the initial growth phases of crop or weed seedlings. EC: See emulsifiable concertrate. Ecdysial cleavage lines: Preformed lines of weakness along which the shed cuticle of the cranium splits during ecdysis; cuticle in the region of these lines lacks the exocuticle (Fig. 100).

F1 generation: The first-generation offspring of a particular mating. F2 generation: Derived from a mating within the F1 generation. Face: The front of the head, below the frontal suture (Fig. 108). Facet: The hexagonal external surface of an individual compound eye unit of ommatidium. Facies: In taxonomy, the general aspect, appearance, or habits of a species or group.

Gain threshold: The beginning point of economic damage, expressed in amount of harvestable produce; when cost of suppressing insect injury equals money to be gained from avoiding the damage. Galea: The lateral lobe of the maxillary stipes; tonguelike, distal lobe attached to the stipes of the maxilla; an apical lobe of the maxilla of an insect; the outer two-jointed lobe of the “pincers” present on the maxilla of insect mouthparts; in adult Lepidoptera the two are joined and enlarged to form the proboscis. (Fig. 63) Gall: Swellings, deformities, or growths of plant tissue that result from the activities various types of pests, including bacteria, nematodes, mites and insects; an abnormal growth of plant tissues, caused by the stimulus of an animal or another plant (Fig. 128). Gallicolous: Living in a plant gall either as the producer or inquiline.

Hard pesticide: One which persists for a long time in the environment; particularly applies to organochlorine insecticides. Habit, Habitus: The general appearance of an organism; facies. Habitat modification: Alteration of the environment where an organism occurs, e.g., cultivating land for agriculture. Habitat: The environmental conditions and associated organisms that occur in a particular site; the place where plants and animals live, usually with a distinctive boundary (e.g. field, pond, sand-dune, rocky crevice); the natural or usual dwelling place of an individual or group of organisms. (L. habitus = condition). Habituation: A form of associative learning in which a given stimulus no longer elicits a response; learning not to respond to a stimulus that provides no reward or punishment. Habituation: Reduction in the response to a stimulus with repeated exposure, through modification of the central nervous system. Haematophagous: Blood-sucking; blood –feeding. Haemocoel (also hemocoel): The main body cavity of many invertebrates, including insects, formed from an expanded ‘blood’ system that is filled with blood (haemolymph) within which the internal organs lie.

Ichthyology: Science dealing with the study of fishes – a class of aquatic vertebrates most of whom depend for respiration exclusively on oxygen dissolved in water (Gr. ichtys = fish + logos = study). Idiobiont: A parasitoid that prevents its host from developing any further, by paralysis or death; see also Konobiont. IGR: See insect growth regulator Ileum: The second section of the hindgut, preceding the colon differentiated region of the anterior intestine of the hindgut preceding the rectum in some insects (Fig. 120). Imaginal buds: See imaginal disc.

Jet: Liquid emitted from a nozzle orifice (in USA = nozzle). JH: An abbreviation of juvenile hormone. Johnston’s organ: A sense organ similar to a chordotonal organ, located in the second antennal segment of most insects; functions in sound reception in some Diptera (Fig. 153); an organ in the pedicel of the antenna, consisting of a cluster of chordotonal sensilla.

Kairomone: A chemical produced by an individual of one species that has a beneficial effect on the recipient individual of another species; a chemical that is adaptively favourable to the receiving organism; an interspecific messenger substance that benefits the receiver but not the releaser (e.g., attractants, excitants); an interspecific chemical messenger that benefits the receiver but not the emitter; a communication chemical that benefits the receiver and is disadvantageous to the producer; see also Allomone; Synomone. Karyological character: A character involving chromosome structure or number (cf. Taxonomic character). Keeled: With an elevated ridge or carnia. Keratin: The inert exoskeleton protein of vertebrate animals forming skin, hair, feathers, claws, nails, scales, etc.; similar in structure and function to the arthropod chitin. Keratolytic: Pertaining to or promoting loosening or separation of the outer layer of the skin.

Label: Technical information about a registered pesticide in the form of printed material attached to, or printed on, the pesticide container. It is illegal to use the pesticide in ways inconsistent with the label. Labella (sing. labellum): In certain flies, paired lobes at the apex of the proboscis, derived from labial palps; apical spongelike structure on the proboscis of nonbiting muscoid flies (Fig. 156).

Macro: Large. Macro-and microconsumers: In an ecosystem the primary consumers, feed on plants while other consumers, e.g., secondary and tertiary consumers are called macroconsumers. The decomposers, like bacteria and fungi, are called microconsumers. Macro-and micronutrients: Some salts or elements needed in relatively large amount are termed macronutrients while some others though essential for maintaining the life-system are required in minute amounts and are the micronutrients. Macroclimate: General climate prevailing over a large area, considered as a unit. The opposite is microclimate. Macroevolution: Major phylogenetic patterns that develop over wide spans of geological time. Macrofauna: The larger members of a particular fauna. Open to different levels of interpretation for they may be larger vertebrates or alternatively the larger insects of a habitat. The opposite is microfauna. Macrogamete: The female gametocyte of a malaria parasite, Plasmodium spp; see also Microgamete. Macrophage: An eater of large particles; see also Microphage.

Naiad: The immature stage in insects with incomplete metamorphosis that feed and develop in water; an aquatic, gill-breathing, immature instar of hemimetabolous insect. Narcotic: A chemical that causes reversible depression of the nervous system. Narrow spectrum (as applied to insecticides): Having an effect on only a narrow range of insects. Nasus: A nose, the snout of certain termite soldiers (nasutes). Nasute (pl. nasuti): A type of soldier caste in certain termites; this form bears a median frontal rostrum or snout through which it ejects a defensive fluid; the jaws are small or vestigial. Nasutus (pl., nasuti): An individual of a termite caste in which the head narrows anteriorly into a snoutlike projection. Natality: Population ‘increase’ factor; birth rate; often measured as total number of eggs or eggs per female per unit of time.

Objective synonym: An absolute or nomenclatural synonym resulting from the proposal either of a replacement name for a supposedly preoccupied name or of names based on the same specimen, illustration, or taxonomic entity (cf. Synonym, Subjective synonym). Obligate parasite: A parasite that requires a living host to survive and reproduce and which cannot exist in any other way. Obligatory: Compulsory, or exclusive; e.g. obligatory diapause is a resting stage that occurs in every individual of each individual of each generation of a univoltine insect. Oblique sternals: Lateral abdominal muscles in other than longitudinal or dorsal-ventral orientation

Pacemaker: A region from which waves of contraction in the heartbeat cycle are propagated. Paedogenesis: Reproduction by the juvenile form; the production of eggs or young by an immature or larval stage of an animal; reproduction by larviform individuals. Paeudotrachea: A ridged groove on the ventral surface of the labellum of some higher Diptera, used to take up liquid food. Page precedence: The principle that when two or more conflicting homonyms or synonyms are published in the same work (or portion of a work) and, as a consequence, are of the same date, the names shall have priority according to the sequence in which they first appear in the work (or portion) concerned. Paint gun: Type of small, hand-carried, air-blast machine. Pair-wise coevolution: see Specific coevolution.

Quadrangle: A cell immediately beyond the arculus (Odonata, Zygoptera). Quadrat: A four-sided defined area from which a sample is collected, used in population determination. Quadrivoltine: Four life cycles per year. Qualitative defenses of plants: Toxins and small-molecular-weight compounds (such as alkaloids) that are active against the physiological systems of phytophagous insects; complex, digestibility-reducing substances (such as tannins) that reduce the ability of insects to feed on plants. Quantitative specificity: In serology, the principle that a given kind of antibody will react more strongly, under comparable conditions, with the particular kind of antigen used in its formation than with any other substance (cf. Antibody, Antigen, and Precipitin reaction).

Race: A subspecific category that is based on particular attributes, such as behavioral or physiological (other than morphological) differences; similar to a subspecies; often used in describing plant pathogens. Race: Subspecies (q.v.). Race: A naturally occurring group within a species usually visually indistinguishable but with some physiological difference from other members of the species, e.g., with a different plant host range. cf. strain. Radial cell: A cell bordered anteriorly by a branch of the radius; the marginal cell (Hymenoptera). Radial cross vein: A cross vein connecting R1 and the branch of the radius immediately behind it. Radial sector: The posterior of the two main branches of the radius. Radiation: See Adaptive radiation.

Sabadilla: A botanical insecticide extracted from seeds of Schoenocaulon officinale Safener: A chemical additive that reduces the phytotoxic properties of a pesticide. Salivarium or salivary reservoir: The cavity into which the salivary gland opens, between the hypopharynx and the labium. Salivary gland: The exocrine gland that produces saliva and typically associated with the labial segment; highly variable in size, structure, and function. Saltation: Discontinuous variation produced at a single step by mutation (cf. Mutation).

Tactile: Referring to the sense of touch. Taenidium (pl. taenidia): The spiral thickening of the tracheal wall that prevents collapse; helical fold in the cuticular lining of tracheae and tracheoles (Fig. 230); cuticular ridges that support the walls of tracheae; a spiral or circular thickening of the inner surface of the tracheae.

Ultra low volume spraying (ULV): The application of pesticides in extremely concentrated or undiluted form using 10 liters or less per hectare (1 gal per acre); highly concentrated pesticide applied without dilution at a rate of 0.5 gallons per acre or less. Umbilical cord: The cord containing blood vessels supported by connective tissue that unites the embryo or fetus of a mammal with the mother during development in the uterus. (L. umbilicus = navel). Ungulate: Having hoofs, as a deer or (L. ungula = hoof). Unguligrade: Walking or adopted for walking on hoofs. (L. ungula = hoof + gradior = to step). Ungue: Pretarsal claw. Unguiculate: Having claws, as a cat. (L. unguis = claw).

Vagina: A pouch-like or tubular genital chamber of the female genitalia; external opening of the female reproductive system; or the terminus of the female reproductive tract that opens to the outside; or the terminal portion of the female reproductive tract which receives the copulatory organ of a male in mating (L. sheath). Valid name: The name of a taxonomic category which is available nomenclaturally and also is recognized as valid on Zoological grounds (cf. Available name). Valvar lamina: The posterior margin (usually prolonged posteriorly) of the eighth abdominal sternite (female Odonata). Valve: In animals, any structure that limits or closes an opening; the thin folds in veins, lymph vessels, or hearts or the circular muscles about a tubular exit; also, either external shell of bivalve mollusk, brachiopod, or some crustaceans. Valvifer (s): A basal sclerite of a valve of the ovipositor, articulating with the tergum; or proximal structures of the ovipositor that bear the valvulae; in female insect genitalia, derivations of gonocoxites 8 and 9, supporting the valves of the ovipositor. Valvulae: Distal structures of the ovipositor borne on the valvifers; the three pairs of processes forming the sheath and piercing structures of the ovipositor.

Wettable powder (WP): An insecticide formulation consisting of finely ground solid particles of active ingredient plus inert carrier; forms a suspension when added to water. Waggle dance: A communication dance of honey bees. A form of recruitment in the honey bee in which direction and distance to a food source are indicated. Waiting period: See time interval. Waiting period: The prescribed period between last application of a pesticide to crop and harvest. Warble: The swelling on the host body caused by the larva of a warble fly. Warm-blooded (Homoiothermous): Animals in which body temperature normally does not change with changes in atmospheric temperature e.g.birds and mammals. Warning: Signal word used to designate a moderately toxic pesticide; oral LD50 = 50 to 500 mg/kg body formulated.

Xerophyte: Plant adapted for survival in desert or physiologically dry soil. Xylem: The water-conducting woody tissue in vascular plants. Xylomycetophagy: Cultivation and feeding upon symbiotic fungi growing in woody tree tissues; for example, some Scolytidae. Xylophage (adj. xylophagous): An eater of wood. Xylophagy: Feeding on xylem tissues. Yellow fever: An infectious, mosquito-transmitted viral disease.

References Abrahamson, W. G. 1989. Plant-animal interaction. McGraw-Hill: New York. Berridge, M. J. 1970. A structural analysis of intestinal absorption. In: Neville, A. C., ed. Insect ultrastructure. London: Royal Entomological Society, Symposium 5: p. 135-151. Binnington, K. C. 1993. Ultrastructure of the attachment of the bacteria Serratia entomophila to foregut cuticle of Costelytra zealandica (Coleoptera: Scarabaedae) abd a review of nomenclature for insect epicuticular layers. International Journal of Insect Morphology and Embryology,22 (2-4), 145-55. Birch, M. C. and Haynes, K. F. 1982. Insect Pheromones, Studies in Biology no. 147. Edward Arnold, London. Borror, D. J., Triplehorn, C. A. and Johnson, N. F. 1989. An Introduction to the Study of Insects, 6th edn, Saunders College Publishing, Philadelphia, etc. Chapman, R. F. 1971. The insects – structure and function. 2nd ed. American Elsevier: New York. Chu, H. F. 1949. How to know the Immature Insects, Wm. C. Brown Company Publishers, Dubuque, Iowa. Claassen, P. W. 1931. Plecoptera nymphs of North America (north of Mexico). Thomas Say Foundation Publication No. 3. College Park, MD: Entomological Society of America. Common, I. F. B. and Waterhouse, D. F. 1972. Butterflies of Australia, Angus and Robertson, Sydney. Comstock, J. H. 1918. The wings of insects. Ithaca, NY: Cornell University Press. Cook, B. J.; Holman, G. M. 1985. Peptides and Kinins. In: Kerkut, G. A.; Gilbert, L. I., eds. Comprehensive insect physiology, biochemistry, and pharmacology. Pergamon Press: New York: p. 531-593, vol. 11.