UNIVERSITY OF ILLINOIS LIBRARY AT URBANA-CHAMPAIGN NATURAL HIST. SURVEY Digitized by the Internet Archive in 2011 with funding from University of Illinois Urbana-Champaign http://www.archive.org/details/howtocollectpres39ross ■ i' :'"-•■ mow TfrcimECT and.- Insects. STATE OF ILLINOIS DEPARTMENT OF REGISTRATION AND EDUCATION HOW TO COLLECT AND PRESERVE INSECTS H. H. ROSS Printed by Authority of the State of Illinois NATURAL HISTORY SURVEY DIVISION Harlow B. Mills, Chief Circular 39 Urbana July, 1962 (Sixth Printing, With Alterations) N/-..U „L HISTOkY oU.WtY I 4 1962 LIBRARY STATE OF ILLINOIS DEPARTMENT OF REGISTRATION AND EDUCATIC BOARD OF NATURAL RESOURCES AND CONSERVATION William Sylvester White, Chairman; A. E. Emerson, Ph.D., Biology; Walter H. Newhouse, Ph.D., Geolog Roger Adams, Ph.D., D.Sc, Chemistry ; Robert H. Anderson, B.S.C.E., Engineering; Charles E. Olmsted, Ph. I Forestry; W. L. Everitt, E.E., Ph.D., Representing the President of the University of Illinois; Delyte W. Morrk Ph.D., President of Southern Illinois University NATURAL HISTORY SURVEY DIVISION, Urbona, Illinois SCIENTIFIC AND TECHNICAL STAFF Harlow B. Mills, Ph.D., Chief Bessie B. East, M.S., Assistant to the Chief Section of Economic Entomology George C. Decker, Ph.D., Principal Scientist and Head J. H. Bigger, M.S., Entomologist L. L. English, Ph.D., Entomologist W. H. Luckmann, Ph.D., Entomologist Willis N. Bruce, Ph.D., Entomologist John P. Kramer, Ph.D., Associate Entomologist Richard J. Dysart, Ph.D., Associate Entomologist Ronaid H. Meyer, M.S., Assistant Entomologist William C. Moye, M.S., Assistant Entomologist James W. Sanford, B.S., Technical Assistant Earl Stadelbacher, B.S., Technical Assistant Sue E. Watkins, Technical Assistant H. B. Petty, Ph.D., Extension Specialist in Entomology* Stevenson Moore, III, Ph.D., Extension Specialist in Entomology* Clarence E. White, B.S., Instructor in Entomology Extension* Costas Kouskolekas, M.S., Research Assistant* Victor T. Williams, B.S., Research Assistant* Section of Faunistic Surveys and Insect Identification H. H. Ross, Ph.D., Principal Scientist and Head Milton W. Sanderson, Ph.D., Taxonomist Lewis J. Stannard, Jr., Ph.D., Taxonomist Philip W. Smith, Ph.D., Associate Taxonomist Leonora K. Gloyd, M.S., Assistant Taxonomist H. B. Cunningham, Ph.D., Assistant Taxonomist Ruth P. Cash, Technical Assistant John M. Kingsolver, Ph.D., Research Associate* John D. Unzicker, B.S., Research Assistant* Talaat K. Mitri, M.S., Research Assistant* Section of Aquatic Biology George W. Bennett, Ph.D., Aquatic Biologist and Head William C. Starrett, Ph.D., Aquatic Biologist R. W. Larimore, Ph.D., Aquatic Biologist David H. Buck, Ph.D., Associate Aquatic Biologist Robert C. Hiltibran, Ph.D., Associate Biochemist Donald F. Hansen, Ph.D., Associate Aquatic Biologist William F. Childers, M.S., Assistant Aquatic Biologist Michael G. Johnson, Biochemical Assistant Maryfran Martin, Technical Assistant Robert D. Crompton, Field Assistant Michael J. Duever, Field Assistant Charles F. Thoits, III. A.B., Research Associate* Rollin D. Andrews, III, B.S., Field Assistant* Leslie L. Layton, Field Assistant* Section of Applied Botany and Plant Pathology J. Cedric Carter, Ph.D., Plant Pathologist and Head J. L. Forsberg, Ph.D., Plant Pathologist G. H. Boewe, M.S., Associate Plant Pathologist Robert A. Evers, Ph.D., Associate Botanist Robert Dan Neely, Ph.D., Associate Plant Pathologis E. B. Himelick, Ph.D., Associate Plant Pathologist Walter Hartstirn, Ph.D., Assistant Plant Pathologist D. F. Schoeneweiss, Ph.D., Assistant Plant Pathologis, Anne Robinson, M.A., Technical Assistant Section of Wildlife Research Thomas G. Scott, Ph.D., Wildlife Specialist and Head I Ralph E. Yeatter, Ph.D., Wildlife Specialist F. C. Bellrose, B.S., Wildlife Specialist H. C. Hanson, Ph.D., Associate Wildlife Specialist Richard R. Graber, Ph.D., Associate Wildlife Specialii Glen C. Sanderson, Ph.D., Associate Wildlife Speciali Ronald F. Labisky, M.S., Associate Wildlife Specialist Marjorie J. Schlatter, Technical Assistant Richard Bartholomew, B.S., Technical Assistant Howard Crum, Jr., Field Assistant Jack A. Ellis, M.S., Project Leader* Bobbie Joe Verts, M.S., Project Leader* Ralph J. Ellis, M.S., Project Leader* William L. Anderson, B.S., Assistant Project Leader* James A. Harper, M.S., Assistant Project Leader* David A. Casteel, B.S., Assistant Project Leader* Gerald G. Montgomery, M.S., Research Associate* John E. Warnock, M.S., Research Associate* Duane E. Newman, M.S., Research Associate* William R. Edwards. M.S., Research Associate* P. J. Rao, B.V.Sc, M.A., Research Assistant* Richard W. Lutz, M.W.M., Research Assistant* George B. Joselyn, M.S., Research Assistant* Richard D. Andrews, M.S., Field Mammalogist* Gerald L. Storm, M.S., Field Ecologist* Keith P. Dauphin, Assistant Laboratory Attendant* Section of Publications and Public Relations James S. Ayars, B.S., Technical Editor and Head Blanche P. Young, B.A., Assistant Technical Editor Anne Ruth Dreyfuss, M.A., Assistant Technical Editi Wilmer D. Zehr, Assistant Technical Photographer Technical Library Ruth R. Warrick, B.S., B.S.L.S. Doris F. Dodds, B.A., M.S.L.S., Technical Librarian Technical Librarian CONSULTANTS: Herpetology, Hobart M. Smith, Ph.D., Professor of Zoology, University of Illinois; Paras itologi Norman D. Levine, Ph.D., Professor of Veterinary Parasitology and of Veterinary Research, University of Illinois Wildlife Research, Willard D. Klimstra, Ph.D., Professor of 'Zoology and Director of Co-operative Wildli) Research, Southern Illinois University; Statistics, Horace W. Norton, Ph.D., Professor of Agricultural Statistic! Design and Analysis, University of Illinois. ♦Employed on co-operative projects with one of several agencies: University of Illinois, Illinois Agricultur: Extension Service, Illinois Department of Conservation, National Science Foundation, United States Department c Agriculture, United States Fish and Wildlife Service, United States Public Health Service, and others. This paper is a contribution from the Section of Faunistic Surveys and Insect Identification. (55352— 10M— 5-62) CONTENTS Where to Collect 1 What to Use 2 Nets 3 Killing Bottles 6 Aspirators or Suckers 9 Sifter 12 Berlese Funnel 12 Equipment for Collecting Aquatic Insects 16 How to Handle Unmounted Specimens 17 Temporary Cases 17 Relaxing Boxes and Jars 19 How to Mount and Preserve Specimens 29 Preservation by Pinning 20 Spreading Board for Moths and Butterflies 24 Preservation in Fluid 26 How to Label the Specimens 26 Housing the Collection Permanently 27 Insect Boxes 27 Precaution Against Pests 27 The Insect World 28 How to Identify Specimens 34 Synopsis of Illinois Insect Orders 35 Primitive Wingless Insects 35 Diplura, 36 Collembola, 36 Microcoryphia, 36 Protura, 36 Thysanura, 38 Primitive Winged Insscts 38 Ephemeroptera, 38 Odonata, 38 Folding-Wing Insects 40 Cursoria, 42 Phthiraptera, 45 Coleoptera, 53 Isoptera, 43 Mallophaga, 47 Hymenoptera 54 Orthoptera, 43 Anoplura, 47 Mecoptera, 55 Dermaptera, 44 Thysanoptera, 47 Trichoptera, 57 Plecoptera, 45 Hemiptera, 48 Lepidoptera, 58 Zoraptera, 45 Megaloptera, 52 Diptera, 60 Corrodentia, 45 Neuroptera, 52 Siphonaptera, 61 Relatives of Insects 62 Isopoda, 62 Pseudoscorpionida, 64 Acarina, 65 Amphipoda, 62 Phalangida, 64 Diplopoda, 66 Scorpionida, 64 Araneida, 65 Chilopoda, 67 The State Insect Collection 67 Reports on Illinois Insects 69 Useful Books 70 How to Ship Specimens 70 Where to Buy Supplies 71 Printed by Authority of the State of Illinois, Ch. 127, IRS, Par. 58.22. Illinois streams are a source of many insects of interest to the amateur collector. Shown here is the Salt Fork River, south of Oakwood. HOW TO COLLECT AND PRESERVE INSECTS' H. H. ROSS WITH rather simple equipment, the amateur as well as the trained entomologist can make a worthwhile collection of insects. The making of such a collection may have educational and recrea- tional as well as scientific values. Developing this hobby is one of the finest ways for students, especially those in agricultural districts, to become acquainted with the large number of injurious and beneficial insects that they encounter about the home and in the fields. High school classes in biology find excellent laboratory material in the many insects available for rearing and study. Both old and young collectors find a great deal of pleasure in working with the showy and beautiful insects, such as beetles, moths, and butterflies ; the satisfaction derived comes both from having relaxation from the day's work and from making real contributions to scientific knowledge. Many entomological museums welcome the opportunity to examine carefully prepared and labeled collections. These collections supply distribution records for insect species, in addition to other information of value to tech- nical entomologists. Also, the amateur collector profits from his contact with specialists who can help him identify his specimens and advise him at any stage of his work. It is hoped that this circular will show how easy it is to make a start in insect collecting and will give the student helpful ideas on how and where to begin. WHERE TO COLLECT In late spring, in summer, and in early fall, insects are very abundant in fields and woods, and large numbers of them may be caught by sweeping through the grass and branches with a strong insect net. Flowers of all descriptions are favorite visiting places of many bees, flies, beetles, and other insects, and will afford good col- lecting. Woods along the banks of streams, open glades in deep woods, and brush along forest edges offer some of the best opportunities for collecting by the sweeping method. In early spring, when insects can be taken only sparingly in the open, the collector frequently finds sheltered hollows where they may [l] 2 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 39 be caught in large numbers. A certain kind of insect may live only on a certain kind of plant, and to obtain the insect the collector must search or sweep the plant, called the host plant. Many obscure places harbor insects seldom found elsewhere. Among these are leaf mold and debris on the surface of the soil, particularly in woods ; rotten logs and stumps, which should be turned over to reveal insects that hide under or around them, and then care- fully searched or torn apart for others that live inside ; in, under, and around dead animals; under boards and stones. Trees sometimes yield valuable specimens. If part of a tree, under which has been spread a large white sheet, is struck with a heavy, padded stick, many insects, such as weevils, will fall to the sheet and "play possum." They can be picked off quite easily. Lights attract large numbers of certain nocturnal insects, such as June beetles and many kinds of moths ; at night these insects may be collected at street or porch lights, on windows and screens of lighted rooms, or at light traps put up especially to attract them. Swarms of aquatic insects come to street lights of towns along rivers, sometimes in such numbers as to pile up in a crawling mass under each light. Collecting at this source is best on warm, cloudy nights; wind or cold keeps most nocturnal insects fairly inactive. Different species of moths and beetles visit the lights in different seasons so that collecting by this method alone yields many kinds of insects. Insects that live in the water may be collected with heavy dip nets swept through the water at various levels and through the mud and debris at the bottom. In shallow water, many insects will be found if stones and logs are turned over and leaf tufts pulled apart. In winter, insect galls or cocoons may be gathered. If these are placed in jars with cheesecloth covers tied over them, kept in a warm room, but away from radiators and all intense heat, many insects will emerge from them before spring. WHAT TO USE For making even a fairly large insect collection, only a small amount of equipment is required. A net and killing bottle are essential, and good work may be done with these alone. A greater variety of in- sects may be collected and with better results if a few more items are added to the list. Here is an outfit that will be found very satisfactory in the field. 1. A strong beating net for general sweeping and an additional light net to be used for moths and butterflies. ROSS: HOW TO COLLECT AND PRESERVE INSECTS 3 2. Killing bottles, several small and one or two large ones. 3. A pair of flexible forceps, 10 to 12 centimeters (about 4 to 5 inches) long, with slender prongs. 4. One or two camel's-hair brushes for picking up minute insects. 5. A few vials or small bottles containing fluid preservative. 6. Folded papers for butterflies. 7. A few small tins or boxes lined with cellucotton. These items may be purchased from commercial supply houses such as those listed on page 71. Many items, however, may be made by the collector at nominal cost. Nets Nets are the most important items in the collecting kit of the entomologist. For this reason nets should be rigidly constructed and handled with care. Construction. — Nets may easily be made at home. The necessary parts are a handle, a loop or ring to be attached to it, and a cloth bag to be hung from the loop, figs. 1 and 2. The handle should be strong and fairly light. At the net end, fig. la, a groove is cut down each side to receive the arms of the loop. The grooves are as deep as the thickness of the wire used in the loop ; one groove is 3 inches long and the other 2!/2 inches ; and each ends in a hole through the handle at right angles to the length. The loop, fig. lb, is made of steel wire, preferably three-eighths- inch piano wire, which if bent by rough usage springs back into shape and will stand a great deal of hard wear. The wire is shaped, as the figure shows, to form a loop with two straight arms, the tips of which are bent at right angles toward each other. The arms and hooks thus formed must be exactly long enough to fit along the grooves and into the holes in the handle. After the bag or net has been attached to the loop, and the wire has been fitted to the handle, the joint may either be wrapped tightly with wire, fig. lc, or bound by a metal cylinder or ferrule slipped over the arms of the loop, fig. Id. The bag, about twice as long as the diameter of the loop, should be tapered at the bottom. It is made from four pieces of cloth, each cut in the shape of fig. 2a, and a narrow strip or band of stout muslin or light canvas, 26, which is to bind the bag to the wire loop. The four pieces are sewed together to form a cone-shaped bag, and one edge of the band is sewed to the top edge of the bag. The bag may be attached to the wire loop in either of two ways. The band may be folded over the loop and sewed so that the attach- ment is permanent ; or it may be folded over, sewed, and then slipped on the loop before the latter is fastened to the handle. In the latter 4 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 39 case the bag must be open along one seam just below the handle a sufficient distance to allow the band to slip on and around the loop ; this vent may be closed with a string lacing after the net is on the loop, and the whole fastened to the handle. A combination of this arrangement with a ferrule binding the loop to the handle is most lo CLOTH COVER ETHYL ALCOHOL Fig. 7. — Diagrammatic cross section of a Berlese funnel. The central figure shows an arrangement for a steam coil, the lower left for an electric light. funnel, suspended wide end up, with a screen placed about a third of the way down the funnel ; heat is applied either around the upper portion or over the top of the funnel, and a container of preservative, preferably 80 per cent ethyl alcohol, is placed at the small bottom opening. Leaf mold or other material is placed on the screen, the heat source is turned on, and soon the animals begin to leave the drying sample and migrate downward, dropping into the preservative. Fig. 7 illustrates a funnel that has proved very satisfactory ; it is 15 inches from top to bottom, and the top has a diameter of 12 inches. The bottom opening, seven-eighths inch in diameter, fits into the mouth of the bottle containing the preservative. Three angled brackets or hangers are soldered inside the funnel to provide a rest for the screen, which is made of quarter-inch or eighth-inch mesh hardware cloth; the mesh used depends upon the type of sample. A battery of several funnels in a rack, fig. 8, will allow the collector to sample several kinds of material at the same time. If steam is used as a source of heat, the small copper lines that conduct it act as a partial support for the funnel by encircling it about 14 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 39 halfway between the screen and the top ; a piece of cloth is tied tightly- over the top of the funnel to prevent the upward escape of animals. If an electric light is used for heating, it should be hung directly over the center of the funnel, no cloth should be tied over the top, and the light should have a reflector nearly as wide as the top of the funnel. Care must be taken not to heat the sample too rapidly. Otherwise, either moisture will condense in the lower part of the funnel and trap many of the animals working their way toward the bottom, or the heat will kill many of the organisms before they have an opportunity Fig. 8. — Berlese funnel in position on rack. Each funnel rests inside a double ring of copper tubing (visible at extreme lower left), through which live steam flows. The steam produces heat that dries out the sample of leaf mold in the funnel and drives animals into a bottle of preservative below. Cotton or a small rag is tamped between the end of the funnel and the mouth of the bottle to prevent escape of specimens. ROSS: HOW TO COLLECT AND PRESERVE INSECTS 15 to move out of the sample. An application of heat sufficient to dry the sample in 4 or 5 days is usually satisfactory. The Berlese funnel is extremely useful for collecting many groups of beetles (particularly Staphylinidae), thrips, springtails, many groups of parasitic Hymenoptera, ants, mites, pseudoscorpions, mil- lipedes, centipedes, and a wide range of other minute animals that live in soil, surface cover, logs, or bark. Collecting Berlese Samples. — Many different habitats and micro- habitats provide good samples for the Berlese funnel. You will find that, for general collecting, various types of ground cover are excel- lent; for leaf mold samples, scrape off and discard the dry surface leaves and scoop up the lower, rotted layers of leaves together with an inch or two of the adjacent soil. You may encounter especially good samples where leaves have blown in along the edge of a log. In such a situation, take some of the log bark with the sample. Collect rotten log samples in large hunks and break them up just before putting them in the funnel. From either standing stumps or fallen logs in which the wood is still too hard to break up, collect the loose bark, as it is often quite productive. Frequently, if you roll a log over, you may find animal runs under it; the debris and earth under and around these runs, together with animal nests, frequently give unusual catches, such as larvae and adults of fleas and rare ticks. Especially productive are samples taken from the interior of a standing hollow tree ; from the bottom of the hollow you can scoop out a foot or more of fine, rotten, woody material rich in rare insects. Certain items placed in the funnel may produce distinctive and unusual catches. Recently deserted birds' nests will give mites and, frequently, rare beetles, flies, and their larvae ; mature or overmature mushrooms and bracket fungi are often rich in beetles, thrips, and maggots ; bark of living trees may produce unusual thrips, springtails, and psocids; debris from aquatic habitats and from the wet edges of ponds and tiny streams may be productive of rare aquatic and semiaquatic forms. Moss is a good source of peculiar species of springtails, thrips, and beetles ; the moss should be rolled up carefully while being transported. Handling Berlese Collections. — In the field, put samples of leaf mold or other material in tightly woven cloth bags or strong paper bags for transportation. It is convenient to have small paper bags for mushrooms, nests, and other small items, and larger bags for ground cover, moss, and the like. When collecting ground cover and similar material, put in each bag enough of a sample so that it will not shake around loosely, but do not pack it tightly. Be sure that samples do not overheat while being transported. 16 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 39 Samples may be collected at any season. If collected during warm weather, they should be taken to a laboratory and placed in the funnels within a day or two ; otherwise, considerable loss of population occurs within the samples. If collected during cold weather, they may be kept in cold storage for a week or two with little loss of fauna. In putting material in the funnel, lay it carefully on the screen to a depth of a few inches. Moss and sod should be placed upside down in a single layer on the screen. In the case of dense material, pile the sample chiefly around the sides of the funnel and leave an opening in the middle, as shown in fig. 7. After the funnel is loaded, place it in the rack, put the bottle of preservative under it, and apply the heat. By substituting a different kind of collecting bottle at the bottom of the funnel, you may obtain live material for rearing. The exact changes necessary to obtain live material will depend upon your in- genuity and the type of material you desire. Equipment for Collecting Aquatic Insects Hundreds of different kinds of insects are aquatic and offer rich collecting possibilities. In all instances, the immature stage lives in water, but in most of them the adult stage emerges on land or flies in the air. For this reason several types of collecting are needed to obtain a good sampling of aquatic insects. Night Collecting of Adult Insects. — Collecting at lights on warm, cloudy nights, or warm nights without moonlight, gives best results. Two simple methods are as follows: Drive your car to a spot overlooking a stream or lake and turn on the bright lights. Into a shallow pan, such as a pie pan, pour enough alcohol to cover the bottom with one-eighth to one-fourth inch of fluid. Hold the pan directly under a headlight. If aquatic insects are on the wing, they will come to the light and eventually drop in the fluid, which traps them. With a small piece of wet cardboard, you can scrape the entire insect contents of the pan into a small bottle of alcohol, which you should then label, giving date, name of collector, and location. Lights in signs and store windows (especially blue neon signs) near fresh water attract large numbers of aquatic insects. You may capture an insect easily by dipping an index finger in a bottle of alcohol, "scooping up" the insect rapidly on the wet surface, and then dipping it in the bottle. An aspirator also can be used with success. Day Collecting of Adult Insects. — During the day, aquatic insects frequently rest on or under bridges, window ledges, and similar places, and show a preference for dense trees in shaded situations. ROSS: HOW TO COLLECT AND PRESERVE INSECTS 17 They are especially numerous in those spots where the heavily leaved branches hang low over the water and form humid, protected areas in the heat of the day. Here sweeping with a stout and fairly wide- mouthed net is very effective. Aquatic insects may often be picked off stones in such places, especially early in the season. Collecting Larvae. — Practically every stream or lake has some aquatic insect larvae which may be collected by various methods, some simple and others requiring specialized and complicated ap- paratus. For general collecting, the following suggestions may be of value : 1. Look under logs and stones. Search out crevices in them; some insects hide away and demand of the collector a keen and careful search. 2. Tear apart bunches of leaves, roots, and other debris that may have piled up in front of a rock or log, or that may have accumulated at the end of a root or branch dangling in the water. 3. Pick out bunches of aquatic plants and search through them carefully. 4. Sift mud, sand, or gravel taken from the bottom of a lake or stream. Remember that some insects build cases in which they hide when disturbed. It takes a practiced eye to see a motionless case. After an insect has dried out a little, it partially emerges from the case and drags it along in search of water ; moving in this way, it is easy to see. HOW TO HANDLE UNMOUNTED SPECIMENS Soon after insects are killed they dry out, become very brittle, and are damaged easily. Small, fragile insects especially are suscep- tible to breakage and, when dry, break up readily into fragments. Hard-shelled insects, such as beetles, may appear to be sufficiently durable to withstand handling when dry, but even these insects have fragile legs, antennae, and other parts which snap off readily when handled dry. Newly killed material should be either mounted or put in temporary storage before it has dried out. If collected material dries out before it can be mounted or stored, it should be relaxed by special techniques so that the specimens can again be handled without danger of breakage. Temporary Cases If it is not convenient to mount the specimens when they are taken from the killing bottle, the moths and butterflies should be put in papers and other insects in cellucotton. 18 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 39 Papers are simply rectangular strips of paper of convenient size folded as in fig. 9. A moth or butterfly, with its wings folded, is placed in a paper, the edges of which are then crimped over to lock it shut. For insects other than moths or butterflies, cardboard pillboxes containing cellucotton make good temporary housing, fig. 10. A layer of cellucotton is laid in the bottom, a layer of insects placed on it, and another layer of cellucotton placed over the insects. The lid should fit fairly snugly over all. Cigar boxes and other boxes of like size also may be used in the same way. Great care must be taken that sufficient cellucotton is put in the box to take up all moisture in the insect bodies. If the specimens are large, they should be allowed to dry moderately uncovered before being placed in cellucotton in storage containers. If insects become damp in the containers they quickly mold or rot. The containers f / / r \ jb / b \ i i i -^ /