Caddisfly Caste

Total Page:16

File Type:pdf, Size:1020Kb

Caddisfly Caste Encyclopedia-C.qxd 11/9/02 5:25 PM Page 151 C in which the concept has been used and the array of important Caddisfly phenomena caste encompasses in different insect societies. see Trichoptera REPRODUCTIVE CASTES Differences in Reproductive Function A fully social or eusocial group is generally understood to exhibit reproductive division of labor. This means that eusocial groups must include some individuals that forgo direct Caste reproduction and instead aid the rearing of the offspring of others in their group. In eusocial insects, the helpers comprise Sean O’Donnell the worker caste and reproductive females are referred to as University of Washington queens. Termite colonies possess long-lived royal couples (a queen and a king), whereas in eusocial Hymenoptera, males he term “caste” refers to long-term, stable differences among are sometimes referred to as drones. Males in the order Tinsect colony members that affect the roles played by Hymenoptera (bees, ants, and wasps) rarely work for their individuals in their social group. It was the existence of distinct colonies and typically die soon after mating. In contrast, male morphological castes in insect colonies that led Charles Darwin eusocial thrips (Thysanoptera) and termites (Isoptera) comprise to identify social insects as a major challengePROOF to his theory of part of the worker force and participate fully in colony labor. evolution by natural selection. Few topics are more central to Social insect species vary according to whether the group’s the study of social insect biology than caste. It is ironic, then, members are permanently relegated to reproductive versus that few topics have generated more controversy and debate worker roles and in the degree of fecundity differences between among social insect biologists. Beyond the deceptively simple reproducers and workers. There is a general evolutionary definition just offered, there is little agreement on how the trend toward increased reproductive caste specialization as term should be defined, or on what characteristics should be more complex, larger societies evolve from smaller, simpler used to identify the castes of individual insects. In part, the ones. In some ants, workers lack reproductive organs and are controversy exists because published definitions of caste are permanently sterile. In most species, however, workers can often not operational. For example, some definitions do not achieve limited direct reproduction under some conditions. specify whether caste differences must be developmentally fixed and permanent or, alternatively, whether individuals can Morphological Differences exhibit caste flexibility. As a result, “caste” has been applied to a wide array of physiological and behavioral phenomena. Some species are reproductively monomorphic, and repro- The diversity of caste systems between and within evolu- ductives do not differ significantly in body structure from tionary lineages of social insects may preclude a simple, uni- workers. Many sweat bees and bumble bees, some paper wasps, versal definition of caste. Rather than advocate a single defi- and even some primitive ants are examples of reproductively nitional point of view, this article explores the diversity of ways monomorphic species. Workers in monomorphic species are 151 Encyclopedia-C.qxd 11/9/02 5:25 PM Page 152 152 Caste often smaller than reproductives, but there can be considerable as the sole reproductive. Subordinate Polistes females function overlap in body size distributions among the reproductive castes. as workers. In some cases, clear physiological differences distinguish workers from reproductives when morphology does not. For example, temperate Polistes paper wasp colonies produce gynes (potential CASTES IN THE WORKER FORCE female reproductives) at the end of the summer. Gynes possess Morphological Castes enlarged, nutrient-laden fat bodies, not present in female workers, that permit them to overwinter in a quiescent state. Discrete Worker Morphology In all termites and in In contrast, consistent reproductive caste differences in approximately 10% of ant species, workers exhibit body size and shape have evolved in several lineages of social developmental allometry resulting in body shape variation insects. Most eusocial insects with wingless workers, such as within the worker caste. Interestingly, this type of ants and termites, retain a morphologically distinct morphological caste has not been documented in social reproductive caste with wings. In species with flying workers, insects with flying workers, such as bees and wasps. There is developmental allometry can still result in the production of typically some association between a worker’s body form and distinct, nonoverlapping body forms for reproductives and the tasks that she performs. One of the most common types workers. Morphologically discrete reproductive castes are of morphological specialization is the assignment of large found among honey bees, stingless bees, and some paper workers, called soldiers, to the special role of colony defense. wasps. Reproductives are often larger than workers, but also When the colony is threatened by an animal, the soldiers differ in body proportions (hence shape) in ways that suggest advance and attack, while other workers flee. Often the specialization in egg laying, such as relatively enlarged soldiers uniquely possess heavily armored exoskeletons and abdomens. The degree of morphological differentiation some type of weaponry, including enlarged muscular heads, between reproductive castes probably evolves in response to a long, piercing mouthparts, or glands that produce defensive complex array of natural selection pressures. For example, the chemicals. In other cases, worker body shape variation affects degree to which the colony occupies a defensible, long- the performance of more mundane tasks such as food lasting nest site may in part determine the whether queens collection. In army ants (Eciton spp.), longer-legged workers can afford to adopt relatively immobile body forms. select larger food items to carry back to their colonies. In leafcutter ants (Atta spp.), the largest workers are soldiers, the medium-sized workers cut and transport leaves, and the Caste Determination: Immature Development and smaller workers usually remain in the nest to tend the Adult Interactions colony’s fungus garden. An ant worker’s body size and shape Other than an interesting exception in the ant Harpagoxenus are fixed upon adult emergence; further growth is not sublaevis, there are no well-documented cases of genetic possible. In contrast, some termite workers (Zootermopsis differences that affect reproductive caste differentiation. spp.) exhibit considerable caste plasticity, potentially molting Often caste differentiation must depend in part on among different body forms, and even switching from soldier differential patterns of gene expression during development, to nonwinged reproductive castes under certain conditions. particularly in species with distinct caste morphology. Differences in environmental conditions during immature BODY SIZE EFFECTS Even in monomorphic species, development can have strong effects on an individual’sPROOF caste. body size differences can influence the tasks that workers Nutritional effects on reproductive caste have been docu- perform. In some species, larger-bodied workers dominate mented in numerous taxa and appear to be widespread, if not their smaller nestmates (Polistes metricus, P. fuscatus, and P. universal, among eusocial insects. Differences in the amount dominulus), and dominance status in turn affects the tasks a of food provided to larvae may underlie many of the dif- worker performs. In some bumble bees (Bombus spp.), ferences between reproductives and workers, especially in however, larger workers are more likely to perform certain species exhibiting the common pattern of larger body size for tasks such as foraging to collect food for the colony, reproductives. However, differences in food quality, possibly independently of obvious worker aggression. including the addition of glandular secretions and pheromones, cannot be ruled out. Especially interesting in Behavioral Castes this regard are eusocial wasps, whose reproductives are smaller than workers (genus Apoica) or identical in size but Workers can be assigned to behavioral castes when they different in shape (genus Pseudopolybia). specialize on a subset of the tasks that the colony needs. In Social interactions among adults may also influence some eusocial insect species such as Bombus and Polistes, reproductive caste, particularly in species without apparent workers exhibit a great deal of flexibility, switching among morphological caste differences. For example, dominance tasks often, and behavioral castes are weakly defined. In honey interactions among paper wasp (Polistes) females, which often bees (Apis mellifera) and swarm-founding paper wasps (Polybia cooperate to start new colonies, determine which female acts spp.), on the other hand, workers specialize more consistently. Encyclopedia-C.qxd 11/9/02 5:25 PM Page 153 Caste 153 AGE OR TEMPORAL POLYETHISM Changes in task through the sequence. Changes in hormone titers, such as specialization as workers age are among the best-studied juvenile hormone, have been implicated in determining the factors that influence workers’ behavioral caste. “Age” or rate of temporal polyethism in Apis and Polybia. “temporal polyethism” refers to an ordered, predictable Workers’ relative age influences
Recommended publications
  • A Remarkable Caddisfly with Bipectinate Antennae in Cretaceous
    Cretaceous Research 69 (2017) 198e203 Contents lists available at ScienceDirect Cretaceous Research journal homepage: www.elsevier.com/locate/CretRes Short communication A remarkable caddisfly with bipectinate antennae in Cretaceous Burmese amber (Insecta, Trichoptera) * Wilfried Wichard a, Bo Wang b, c, a Institute of Biology, University of Koeln, Gronewaldstr. 2, D 50931 Koeln, Germany b State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China c Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Science, Beijing 100101, China article info abstract Article history: A new caddisfly (Trichoptera), Palaeopsilotreta xiai gen. et sp. nov. is described based on three well- Received 8 August 2016 preserved male specimens from mid-Cretaceous Burmese amber. It is assigned to the extant family Received in revised form Odontoceridae. Palaeopsilotreta is similar to the extant genus Psilotreta but differs from the latter by 19 September 2016 partially bipectinate antennae which are unknown among living Trichoptera. Our fossils are not only the Accepted in revised form 28 September only Mesozoic Odontoceridae, but also hitherto the earliest record of this family. 2016 © Available online 29 September 2016 2016 Elsevier Ltd. All rights reserved. Keywords: Taxonomy Fossil caddisfly Palaeopsilotreta xiai Psilotreta Odontoceridae 1. Introduction insights into the evolution of this lineage. In this paper, we describe a new extinct genus and species placed in the family Odontocer- Burmese amber (from northern Myanmar) contains the most idae: Palaeopsilotreta xiai gen. et sp. nov., based on three well- diverse biota in amber from the mid-Cretaceous and more than 250 preserved male specimens.
    [Show full text]
  • Minutes of the January 25, 2010, Meeting of the Board of Regents
    MINUTES OF THE JANUARY 25, 2010, MEETING OF THE BOARD OF REGENTS ATTENDANCE This scheduled meeting of the Board of Regents was held on Monday, January 25, 2010, in the Regents’ Room of the Smithsonian Institution Castle. The meeting included morning, afternoon, and executive sessions. Board Chair Patricia Q. Stonesifer called the meeting to order at 8:31 a.m. Also present were: The Chief Justice 1 Sam Johnson 4 John W. McCarter Jr. Christopher J. Dodd Shirley Ann Jackson David M. Rubenstein France Córdova 2 Robert P. Kogod Roger W. Sant Phillip Frost 3 Doris Matsui Alan G. Spoon 1 Paul Neely, Smithsonian National Board Chair David Silfen, Regents’ Investment Committee Chair 2 Vice President Joseph R. Biden, Senators Thad Cochran and Patrick J. Leahy, and Representative Xavier Becerra were unable to attend the meeting. Also present were: G. Wayne Clough, Secretary John Yahner, Speechwriter to the Secretary Patricia L. Bartlett, Chief of Staff to the Jeffrey P. Minear, Counselor to the Chief Justice Secretary T.A. Hawks, Assistant to Senator Cochran Amy Chen, Chief Investment Officer Colin McGinnis, Assistant to Senator Dodd Virginia B. Clark, Director of External Affairs Kevin McDonald, Assistant to Senator Leahy Barbara Feininger, Senior Writer‐Editor for the Melody Gonzales, Assistant to Congressman Office of the Regents Becerra Grace L. Jaeger, Program Officer for the Office David Heil, Assistant to Congressman Johnson of the Regents Julie Eddy, Assistant to Congresswoman Matsui Richard Kurin, Under Secretary for History, Francisco Dallmeier, Head of the National Art, and Culture Zoological Park’s Center for Conservation John K.
    [Show full text]
  • Amphiesmeno- Ptera: the Caddisflies and Lepidoptera
    CY501-C13[548-606].qxd 2/16/05 12:17 AM Page 548 quark11 27B:CY501:Chapters:Chapter-13: 13Amphiesmeno-Amphiesmenoptera: The ptera:Caddisflies The and Lepidoptera With very few exceptions the life histories of the orders Tri- from Old English traveling cadice men, who pinned bits of choptera (caddisflies)Caddisflies and Lepidoptera (moths and butter- cloth to their and coats to advertise their fabrics. A few species flies) are extremely different; the former have aquatic larvae, actually have terrestrial larvae, but even these are relegated to and the latter nearly always have terrestrial, plant-feeding wet leaf litter, so many defining features of the order concern caterpillars. Nonetheless, the close relationship of these two larval adaptations for an almost wholly aquatic lifestyle (Wig- orders hasLepidoptera essentially never been disputed and is supported gins, 1977, 1996). For example, larvae are apneustic (without by strong morphological (Kristensen, 1975, 1991), molecular spiracles) and respire through a thin, permeable cuticle, (Wheeler et al., 2001; Whiting, 2002), and paleontological evi- some of which have filamentous abdominal gills that are sim- dence. Synapomorphies linking these two orders include het- ple or intricately branched (Figure 13.3). Antennae and the erogametic females; a pair of glands on sternite V (found in tentorium of larvae are reduced, though functional signifi- Trichoptera and in basal moths); dense, long setae on the cance of these features is unknown. Larvae do not have pro- wing membrane (which are modified into scales in Lepi- legs on most abdominal segments, save for a pair of anal pro- doptera); forewing with the anal veins looping up to form a legs that have sclerotized hooks for anchoring the larva in its double “Y” configuration; larva with a fused hypopharynx case.
    [Show full text]
  • Explore the Caddisfly Go.Wisc.Edu/89Z9gt Answer These Before You Watch the Video
    WISCONSIN SEA GRANT ANSWER KEY Explore the Caddisfly go.wisc.edu/89z9gt Answer these before you watch the video... Answer this after you watch... Something I already KNOW about the Something I am CURIOUS about and The most interesting fact Caddisfly want to know I LEARNED FIELD NOTES As you watch the video, jot down observations (what you notice) and new facts in the spaces below. 1 June 2020 Helpful Vocabulary adaptation: modification of an organism or its parts that makes it more fit for living under the conditions of its environment; a heritable physical or behavioral trait that serves a specific function and improves an organism's fitness or survival community: all the living things existing in the same place at the same time dichotomous key: a resource used to identify a species using characteristics and differences between similar species ecosystem: the communities of living and nonliving things interacting in the same space habitat: where an individual organism exists hatch: group of young born at the same time in the same place macroinvertebrate: any animal lacking a backbone and large enough to see without the aid of a microscope. Macroinvertebrates are exothermic (or cold- blooded) and may be aquatic or terrestrial. substrate: the base on which an organism lives 2 June 2020 Field Notes: A Protective Case An unusual thing about the caddisfly is its ability to create a protective case for shelter and protection, using items found in its habitat. Draw a caddisfly in its case. 3 June 2020 Personalize It: A Protective Case Draw or describe (in scientific narrative or in poetry) your own ideal protective case for shelter, using whatever you find or see in your habitat.
    [Show full text]
  • Diversity and Ecosystem Services of Trichoptera
    Review Diversity and Ecosystem Services of Trichoptera John C. Morse 1,*, Paul B. Frandsen 2,3, Wolfram Graf 4 and Jessica A. Thomas 5 1 Department of Plant & Environmental Sciences, Clemson University, E-143 Poole Agricultural Center, Clemson, SC 29634-0310, USA; [email protected] 2 Department of Plant & Wildlife Sciences, Brigham Young University, 701 E University Parkway Drive, Provo, UT 84602, USA; [email protected] 3 Data Science Lab, Smithsonian Institution, 600 Maryland Ave SW, Washington, D.C. 20024, USA 4 BOKU, Institute of Hydrobiology and Aquatic Ecology Management, University of Natural Resources and Life Sciences, Gregor Mendelstr. 33, A-1180 Vienna, Austria; [email protected] 5 Department of Biology, University of York, Wentworth Way, York Y010 5DD, UK; [email protected] * Correspondence: [email protected]; Tel.: +1-864-656-5049 Received: 2 February 2019; Accepted: 12 April 2019; Published: 1 May 2019 Abstract: The holometabolous insect order Trichoptera (caddisflies) includes more known species than all of the other primarily aquatic orders of insects combined. They are distributed unevenly; with the greatest number and density occurring in the Oriental Biogeographic Region and the smallest in the East Palearctic. Ecosystem services provided by Trichoptera are also very diverse and include their essential roles in food webs, in biological monitoring of water quality, as food for fish and other predators (many of which are of human concern), and as engineers that stabilize gravel bed sediment. They are especially important in capturing and using a wide variety of nutrients in many forms, transforming them for use by other organisms in freshwaters and surrounding riparian areas.
    [Show full text]
  • First Record of a Fungus Weevil (Coleoptera; Anthribidae) from the Upper Cretaceous Arzamazovskaya Formation, Primorsky Krai, Russian Far East
    Cretaceous Research 106 (2020) 104246 Contents lists available at ScienceDirect Cretaceous Research journal homepage: www.elsevier.com/locate/CretRes Short communication First record of a fungus weevil (Coleoptera; Anthribidae) from the Upper Cretaceous Arzamazovskaya Formation, Primorsky Krai, Russian Far East Andrei A. Legalov a, b a Institute of Systematics and Ecology of Animals of the Siberian Branch of Russian Academy of Sciences, Frunze Street, 11, Novosibirsk, 630091, Russia b Altai State University, Lenina Street, 61, Barnaul, 656049, Russia article info abstract Article history: A new fungus weevil, Arzamazorhinus neli gen. et sp. nov. belonging to the subfamily Anthribinae is Received 13 May 2019 described from Primorsky Krai, Upper Cretaceous, Turonian e Coniacian. The new genus differs from Received in revised form other genera of the tribe Ecelonerini in the ventral antennal scrobes and rather long rostrum. It is 8 August 2019 distinguished from the genus Cretanthribus Legalov, 2009 (tribe Cretanthribini) fungus weevil described Accepted in revised form 9 September 2019 from Cretaceous deposits of Khetana in the Russian Far East, by the pronotum possessing transverse Available online 16 September 2019 carina, a rather long subparallel rostrum not sagittate at apex, and lacking transverse eyes. This is the first record of Anthribidae from the late Cretaceous and the first coleopteran described from the Arzama- Keywords: Curculionoidea zovskaya Formation in the Russian Far East. © Anthribinae 2019 Elsevier Ltd. All rights reserved. New taxa Primorsky Krai Late Cretaceous Turonian e Coniacian 1. Introduction Cretaceous and the first Coleoptera described from the Turonian e Coniacian of the Arzamazovskaya Formation (Russian Far East). Fungus weevils (family Anthribidae Billberg, 1820) are a very diverse group of primitive weevils adapted for development in 2.
    [Show full text]
  • The Fluctuating Asymmetry of the Butterfly Wing Pattern Does Not Change Along an Industrial Pollution Gradient
    S S symmetry Article The Fluctuating Asymmetry of the Butterfly Wing Pattern Does Not Change along an Industrial Pollution Gradient Vitali Zverev and Mikhail V. Kozlov * Department of Biology, University of Turku, 20014 Turku, Finland; vitzve@utu.fi * Correspondence: mikoz@utu.fi Abstract: The rapid and selective responses to changes in habitat structure and climate have made butterflies valuable environmental indicators. In this study, we asked whether the decline in butterfly populations near the copper-nickel smelter in Monchegorsk in northwestern Russia is accompanied by phenotypic stress responses to toxic pollutants, expressed as a decrease in body size and an increase in fluctuating asymmetry. We measured the concentrations of nickel and copper, forewing length, and fluctuating asymmetry in two elements of wing patterns in Boloria euphrosyne, Plebejus idas, and Agriades optilete collected 1–65 km from Monchegorsk. Body metal concentrations increased toward the smelter, confirming the local origin of the collected butterflies. The wings of butterflies from the most polluted sites were 5–8% shorter than those in unpolluted localities, suggesting adverse effects of pollution on butterfly fitness due to larval feeding on contaminated plants. However, fluctuating asymmetry averaged across two hindwing spots did not change systematically with pollution, thereby questioning the use of fluctuating asymmetry as an indicator of habitat quality in butterfly conservation projects. Keywords: copper-nickel smelter; fluctuating asymmetry; Kola Peninsula; Lepidoptera; phenotypic Citation: Zverev, V.; Kozlov, M.V. stress responses; wing length The Fluctuating Asymmetry of the Butterfly Wing Pattern Does Not Change along an Industrial Pollution Gradient. Symmetry 2021, 13, 626. https://doi.org/10.3390/sym13040626 1.
    [Show full text]
  • Some Ecological Relationships of Mayflies, Caddisflies, and Fish in the Mississippi River Near Keokuk, Iowa " (1965)
    Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1965 Some ecological relationships of mayflies, caddisflies, nda fish in the Mississippi River near Keokuk, Iowa Thomas Lee Wenke Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Zoology Commons Recommended Citation Wenke, Thomas Lee, "Some ecological relationships of mayflies, caddisflies, and fish in the Mississippi River near Keokuk, Iowa " (1965). Retrospective Theses and Dissertations. 2845. https://lib.dr.iastate.edu/rtd/2845 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. This dissertation has been micioiihned exactly as received 66-3909 WENKEi Thomas Lee, 1935- SOME ECOLOGICAL RELATIONSHIPS OF MAYFLIES, CADDISFLIES, AND FISH IN THE MISSISSIPPI RIVER NEAR KEOKUK, IOWA. Iowa State University of Science and Technology Ph.D., 1965 Zoology University Microfilms, Inc., Ann Arbor, Michigan SOME ECOLOGICAL RELATIONSHIPS OF MAYFLIES, CADDISFLIES, AND FISH IN THE MISSISSIPPI RIVER NEAR KEOKUK, IOWA by Thomas Lee Wenke A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of The Requirements for the Degree of DOCTOR OF PHILOSOPHY Major Subject: Zoology Approved: Signature was redacted for privacy. Signature was redacted for privacy. Head of Major Department Signature was redacted for privacy. ramlate College Iowa State University Of Science and Technology Ames, Iowa 1965 PLEASE NOTE: Figure pages are not original copy.
    [Show full text]
  • Ichnoentomology Insect Traces in Soils and Paleosols Topics in Geobiology
    Topics in Geobiology 37 Jorge Fernando Genise Ichnoentomology Insect Traces in Soils and Paleosols Topics in Geobiology Series Editors Neil Landman Peter J. Harries More information about this series at http://www.springer.com/series/6623 Jorge Fernando Genise Ichnoentomology Insect Traces in Soils and Paleosols Jorge Fernando Genise Principal Researcher National Research Council of Argentina Founder, National Ichnological Collection and Division Icnología of the Museo Argentino de Ciencias Naturales President of the First International Congress on Ichnology (Ichnia 2004) ISSN 0275-0120 Topics in Geobiology ISBN 978-3-319-28208-4 ISBN 978-3-319-28210-7 (eBook) DOI 10.1007/978-3-319-28210-7 Library of Congress Control Number: 2016946484 © Springer International Publishing Switzerland 2017 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifi cally the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfi lms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specifi c statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication.
    [Show full text]
  • Caddisfly by Ian Cox Caddis Belong to the Order Trichoptera Which Translates from the Original Greek As Hair Wing. So When We Ta
    Caddisfly By Ian Cox Caddis belong to the order Trichoptera which translates from the original Greek as hair wing. So when we talk of an elk hair caddis we are committing the sin of tautology. Sedge is another name for caddis. They are found throughout South Africa and in all waters, from still to very fast flowing. For more on the caddis and its lifecycle see Caddis Fly. Most of the Caddis’ life is spent underwater as a larvae. Caddis larvae are either cased (which is when the larvae build a protective casing of debris around them) or the free living soft and squidgy larvae which don’t. Cased Caddis larvae are confined largely to the acidic streams of the Western and Southern Cape. In fact only one family of cased Caddis larvae is found outside these streams. They are the Pisuliidae and they construct a case out of twigs. They are also by far the largest member of the caddis having a case of some 2 to 2.5cm in length. Pisuliidae are found throughout South Africa in shady conditions generally where water is slow moving. It is unlikely that you are going to spend much time imitating cased Caddis larvae. For the most part when we imitate Caddis larvae we go for the soft squidgy ones. These do not get very big. They average around the 1 to 1.5 cm mark. South African’s are no strangers to fishing larvae imitations. Put simply the Czech Nymph much loved by those who pursue yellows on the Vaal, while originally a shrimp imitation, has morphed into a case-less caddis larvae.
    [Show full text]
  • Dichotomous Key to Orders
    FRST 307 Introduction to Entomology KEY TO COMMON INSECT ORDERS What is a Key? In biological sciences a “key” is a written tool used to determine the taxonomic identification of plants, animals, soils, etc. For this lab, a key will be used to identify insects to Order. More detailed identifications to family, genus and species are beyond the scope of this course, but can be accomplished using appropriate guides available from the library. Taking a Closer Look Because insects are so small, differentiating among species, families and even orders is often difficult. However, examination beneath a hand lens or microscope will allow you to see many of the characters mentioned in the key. Why Use a Key? Sometimes, you can identify an insect quickly by comparing it to pictures in field guides or on the internet. Pictures are a great tool, but the use of a key is essential to guarantee that your identification is accurate. Why? Because some insects, even ones from separate orders, can look almost exactly alike. For example, many flies (order Diptera) look almost exactly like wasps (order Hymenoptera). Using your key, you will find that a fly has 1 pair of wings, whereas wasps have 2 pairs of wings. Key to Adult Insects Only Remember - immature insects and adult insects are often very different. This is especially true for holometabolous (complete metamorphosis) insects where the immature stages are larvae and pupae. The key included in this guide is only useful for keying adult insects to order. Also, this key does not cover other creatures related to insects, like spiders, sowbugs, and centipedes.
    [Show full text]
  • CADDISFLIES: Six Legs, Often in a Hardened Case of Mineral Or Organic Matter, 11
    CADDISFLIES: Six legs, often in a hardened case of mineral or organic matter, 11. 12. may be ‘free living’ and not in a case. Head distinctly hardened and often patterned, hooks at the end of body, may or may not have gills along abdomen. FREE LIVERS 11. Net Spinning Caddisflies: ‘C’ shaped in the pan, bushy gills underneath body and at tail, builds a retreat to hide in (commonly silken nets with wood or gravel anchors). Net spinners have a head as wide as the thorax of the body. 12. Small Head Caddisflies: These insects resemble net spinners, but have no gills under the body 13. 14. and a much narrower head. They may be white, green or brown, with a fat body and rapid ‘inch-worm’ movement. ORGANIC CASE 13. Stick Bait Caddisflies: 1” – 3” including case, dark brown spots on their yellowish heads. These caddis may be distinguished from other wood and stick cased caddis by the prominent ‘ballast’ pieces of sticks that are attached to the sides of the case. 15. 16. 14. Square Log Cabin Caddisflies: Cases are stouter than other square cases, constructed from wound strips of wood fibers, as opposed to fragments of leaves. Insects greenish or cream colored, prominent brushes of seta on the first pair of legs. 15. Sand and Stick Case Caddisflies: Cases constructed from both mineral and organic materials 17. 18. belong in this category and may be a variety of shapes and sizes. 16. Vegetated Case Caddisflies: This category is for all caddisflies with organic cases that do not fit the other categories above.
    [Show full text]