Ametabolous & Hemimetabolous orders Collembola • Springtails • Minute, most common in soil & leaf litter samples. • Lack wings or obvious mouthparts. • Interesting ‘springtail’ mechanism: tenaculum + furcula. • Often blue/purplish color. Archaeognatha • Bristletails • Large eyes, wingless, external mouthparts. • Arched back, long middle terminal filament. • Covered with scales. Zygentoma/Thysanura • Silverfish & firebrats. • Very small eyes, dorsoventrally flattened, lack wings. • Lateral filaments same length or longer than middle. • Also covered with scales. Hemimetabolous orders Ephemeroptera Odonata Dragonflies (Anisoptera) & Damselflies (Zygoptera) • Sister taxon to Neoptera. • No winged molts. • 6000 species worldwide • Aquatic naiads • Predaceous adults Hemimetabolous orders ORTHOPTERA: Grasshoppers, locusts, katydids, crickets • Largest clade of Polyneoptera: 20,000 species worldwide. • Distinctive saltatory (jumping) hindlegs. • Prothorax large and shield-like. • Two monophyletic suborders: Caelifera and Ensifera. Caelifera • Grasshoppers and locusts • Day-active, fast- moving, visually acute, terrestrial herbivores Ensifera • Katydids • Crickets • Mormon crickets, • Jerusalem crickets • wetas • Cooloola monsters. • Often night-active, camouflaged or mimetic, predators, omnivores, or phytophages. The other Polyneoptera The Dictuoptera/Dictyoptera Mantodea Blattodea Blattodea Blattodea Termitoidae Isoptera Dermaptera Phasmatodea The Paraneoptera Psocoptera • Booklice & Barklice Phthiraptera • Chewing & Sucking lice The Hemiptera • The True Bugs, Cicadas, Leafhoppers, Planthoppers, Spittlebugs, Aphids, Jumping Plant Lice, Scale Insects, Whiteflies, and Mossbugs. • Very diverse morphological assemblage. • What do they all have in common? Hemiptera • All have piercing- sucking beak derived from mandibles and maxillae. • These lie in a beak- like, grooved labium. Classification • Traditionally had been two orders: – Hemiptera (currently considered the Heteroptera + Coleorrhyncha) – Homoptera (currently recognized as a paraphyletic grade) Classification • Currently five suborders 1. Sternorrhyncha 2. Fulgoromorpha 3. Cicadomorpha 4. Coleorrhyncha 5. Heteroptera Sternorrhyncha • Refers to the rearward position of the mouthparts relative to the head. • Numerous plant pests. • Crazy life histories: – Flightless – Parthenogenetic – Sexual dimorphism – Sociality – Cyclical sexual/parthenogenetic Sternorrhyncha: Psylloidea • Jumping plant lice • Resemble miniature cicadas • BUT with long antennae. • Two pairs of clear wings, jumping hindlegs. Sternorrhyncha: Aleyrodoidea • Whiteflies • Distinctive wings with whitish powder. • Similar to aphids but lack cornicles (later). • Giant whitefly a common pest in San Diego. Giant whitefly nymphs Sternorrhyncha: Coccoidea • Scale Insects • Not very insect like: most often encountered stage (adult female) lacks wings, legs, antennae, eyes, etc. • Males have one pair of wings. • Often tended by ants. Sternorrhyncha: Aphidoidea • Aphids • Cornicles conspicuous • Eusociality-ish (soldier, worker, queen castes) known • Alternation of life cycle common Winged Aphids Fulgoromorpha: Fulgoroidea • Planthoppers • Antennae on side beneath eyes • 2 anal veins form a Y-vein Cicadomorpha • Antennae on front between eyes, no Y- vein Cicadomorpha: Cicadoidea • Cicadas • Large, membranous wings • 3 ocelli present Cicadomorpha: Cercopoidea • Spittlebugs & froghoppers • 2 ocelli • Hind tibia with stout spines Cicadomorpha: Membracoidea • Leafhoppers & Treehoppers • Diverse group • Treehoppers (Membracidae): large pronotum that covers the head, extends over the abdomen, and often has peculiar shapes. • Leafhoppers (Cicadellidae): various in size, shape, and colors, but all have one or more rows of small spines extending the length of the hind tibiae. Heteroptera: True Bugs • Beak from the front of the head. • Many plant-feeders, but also predators and hemophages. • Wings cross over body. • Antennae distinctive. Gerridae • Water striders • Distinctive habits & body. Belostomatidae • Giant water bugs & toe-biters. • Very large • Raptorial forelegs • Antennae short, often not visible. Corixidae • Water boatmen • Forelegs modified for swimming • Lots of transverse lines on dorsal surface. Cimicidae • Bed bugs • Dorsoventrally compressed • Wingless Reduviidae • Assassin bugs • Common • Raptorial forelegs • Beak is held in groove in prosternum Miridae • Leaf bugs • Most diverse and common of the Heteroptera • Well-developed cuneus, two cells in membrane of wing. Coreidae • Leaf-footed bugs. • Common. • Very fine striated longitudinal vennation • Often expanded hindlegs. Lygaeidae • Seed bugs • Includes common milkweed bug • Only 1-5 veins in membrane of hemelytron. Rhopalidae • Scentless plant bugs • Similar to Lygaeidae and Coreidae, except that hemelytra has many veins and there is a scent gland present. Pentatomidae • Stink bugs • VERY common, showy, often quite large. • Large, triangular scutellum. .