Phylum Arthropoda THE BIG ONE 99 100 Number

Phylum Arthropoda THE BIG ONE 99

100

Number of species Mollusca Arthropoda Chordata Platyhelminthes Nematoda Porifera Annelida Echinodermata Sarcomastigophora Apicomplex Ciliophora 101

Arthropod Importance • Can not stress how important this group is to: – Biodiversity, evolution, economically • Numbers of species = large impact • Occupy every conceivable niche • Impact on humans – negative & positive – Pests that destroy structures and crops – Spread disease – Provide us with natural products, inc. food 102

Why so successful? 103

Why so successful? 104

Why so successful? 105

Why so successful? 106

General Characteristics of Arthropods White structures in pic above are malpighian tubes 107

Classification of the Arthropods 108

Subphylum Chelicerata: Class Arachnida 109

Subphylum Chelicerata: Class Arachnida Order Scorpiones: Scorpions • • Ancient group Mainly warm climates Live birth Long lived 110

https: //www. youtube. com/watc h? v=ZM 96828 jm. Qk 111

Subphylum Chelicerata: Class Arachnida Order Opiliones: daddy longlegs 112

Subphylum Chelicerata: Class Arachnida Order Araneae: spiders • 40, 000 species • All (but 1) active predators • Chelicerae (first pair appendages) evolved into fangs and inject poison • After prey paralyzed, inject digestive enzymes to liquify, then suck up fluid • Many have silk glands leading to spinnerets on abdomen 113

https: //www. youtube. com/watch? v=EJln-s. Cp. U 98 114

The “Veggie” spider 115

Subphylum Chelicerata: Class Arachnida Order Acari: mites and ticks • Parasitic • No segmentation • Major disease vectors 116

Subphylum Chelicerata: Class Merostomata • Ancient Group (possible trilobite relatives? ) dating to Cambrian explosion • Predators on worms and mollusks • Come to shore in the spring to mate • Females burrow and lay eggs • Long-lived (15+ yrs) https: //www. youtube. com/watch? v=Bm 81 EQ 2 hg. VE https: //www. youtube. com/watch? v=90 LTt. KIFY 8 U 117

Subphylum Crustacea “What insects are to land, crustaceans are to sea” Nauplius 118

Crustacean taxa Subphylum Crustacea Class Remipedia Class Cephalocarida Class Branchiopoda Class Ostracoda Class Maxillopoda Class Malacostraca 119

Subphylum Crustacea: Class Ostracoda • Seed shrimp • Small and laterally flattened • Superficially resemble bivalves • Antennae used to swim • Feed on detritus and suspended particles • Should be prominent in stagnant water samples https: //www. youtube. com/watch? v=Z 1 fsd KOhv. D 4 120

Subphylum Crustacea: Class Malacostraca Order Decopoda • Name means “Ten footed” • 5 pairs of walking legs • Front pair modified into cheliped and used in feeding • Exoskeleton reinforced with calcium carbonate • Segments fused into cephalothorax and covered with carapace • Ancestral biramous appendage highly modified – Locomotion, feeding, respiration, sensory Antenna Uropod Swimmerets Mandible Maxilla Maxillipeds Cheliped Walking legs 121

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Yeti Crab 123

I can’t make this up… hyperlink 124

Mantis Shrimp https: //www. youtube. com/wa tch? v=F 5 FEj 9 U-CJM https: //www. youtube. com/watch? v =U 11 Dgbefm. QQ 125

Crabs • • • Infraorder Brachyura Abdomen short and hidden Thick exoskeleton Terrestrial, freshwater, marine Single pair of claws 900 sp. Lobster & Crayfish • • • Paraphyletic Infraorder Astacidea Long body, thick muscular tail 5 pairs of walking legs, 3 with claws Commercially important as food Long life-span Rocky ocean floors – to continental shelf Freshwater/terrestrial Omnivorous Shrimp/Prawns • • • Infraorders Caridea & Dendrobranchiata Elongate bodies Elongate and muscular tail Legs weak, swim with swimmerets Terrestrial, freshwater, marine Several thousand sp. Krill • • • Infraorder Euphausiacea Resemble small shrimp Feed on phytoplankton Critical link in food web Vertical migrations to feed where their prey are and stay out of site during day 126

Subphylum Crustacea: Class Malacostraca Order Isopoda • Only major order of crustaceans in which some species are truly terrestrial • Dorso-ventrally flattened • Hard but segmented exoskeleton • Most are detritivores • Approx. 11, 000 sp. • Some species can roll into ball for defense Sowbugs & Pillbugs 127

Subphylum Crustacea: Class Malacostraca Order Cirripedia: barnacles • Adults sessile – attached to substrate • Mantle-like tissue surrounds body and secretes shell • Long legs with setae extended out of shell to filter particulates for food • Hermaphrodites, but use longest penis of any animal (relative to size) to probe nearby barnacles and find someone willing to mate http: //www. youtube. com/watch? v=v 1 SW-pl 2 g. Ys 128

Subphylum Crustacea: Class Malacostraca Order Diplostraca: water fleas 129

Other Terrestrial Arthropods Subphylum Myriapoda Class Chilopoda Class Diplopoda Subphylum Hexapoda Class Insecta 130

Subphylum Myriapoda: Classes Chilopoda and Diplopoda 131

Centipede Feeding 132

Subphylum Hexapoda: Class Insecta • • • Largest group of organisms on earth 1. 1 million named species Estimates suggest as many as 30 million sp. exist 1 ha of tropical rainforest has 41, 000 species Reasons for success? Copyright © Mc. Graw-Hill Companies Permission required for reproduction or display 133

Reason for Insect Success 134

Subphylum Hexapoda: Class Insecta External Features 135

Insect Life Histories 136

The Compound Eye • Type of eye found in insects is highly variable • Many have compound eye – this is ancestral • Made up of many repeating units – called Ommatidia • Forms a composite image 137

Major Insect Orders Coleoptera - beetles Diptera - true flies Lepidoptera - butterflies & moths Hymenoptera - ants, bees, wasps Dermaptera - earwigs Embioptera - web spinners Thysanura - silverfish Psocoptera - bark and book Lice Mallophaga - chewing Lice Anoplura - sucking lice Thysanoptera - thrips Strepsiptera - twisted wing parasites Siphonaptera - fleas Collembola - springtails Hemiptera - true bugs Ephemeroptera - mayflies Odonata - dragonflies & damselflies Plecoptera - stoneflies Orthoptera - grasshoppers and crickets Isoptera - termites Homoptera - cicadas, aphids, leafhoppers Neuropter - lacewings Approximately Trichoptera - caddisflies 25 different orders! 138

Subphylum Hexapoda: Class Insecta Coleoptera Order Coleoptera: Beetles • 500, 000 described species • Front wings thick and hard – cover and protect the flight wings, called elytra • Mouthparts biting or chewing 139

The Bombadier Beetle! https: //www. youtube. com/watc h? v=Tgq. F-ND 2 Xc. Y 140

Subphylum Hexapoda: Class Insecta Order Diptera: true flies • Second largest order (120, 000 sp. ) • Single pair of flight wings • Second set reduced, called balancers • Sucking mouthparts Crane fly Diptera 141

Subphylum Hexapoda: Class Insecta Order Lepidoptera: butterflies & moths • 100, 000+ sp. • Wings may be coupled or separate and overlapping • Wings covered with fine scales • Mouthparts a sucking tube • Larvae: − − http: //www. yout ube. com/watch? v =K 5 qij. I--v 9 E Lepidoptera Silk glands Chewing mandibles 142

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Subphylum Hexapoda: Class Insecta Order Hymenoptera: bees, ants, wasps • 100, 000+ described species • Ovipositor may be modified into a singer (only females can sting) • Social and solitary species • Many with haplo-diploid sex determination mechanism (complicated – take Animal Behavior to learn more) 144

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https: //www. youtube. com/watc h? v=BRGr. I 4 AQG 70 146

https: //ww w. youtube. com/watch? v=f. BZt. Te. R YCqk https: //ww w. youtube. com/watc h? v=38 Wj 4 by. HML 0 147

Subphylum Hexapoda: Class Insecta Order Hemiptera: true bugs • Only insects you can actually call “bugs” • Piercing and sucking mouth • Wings may be present or absent 148

Subphylum Hexapoda: Class Insecta Order Trichoptera: caddisflies • • • Adults look like a moth Larvae are aquatic Sister group to lepidoptera Use silk for numerous functions – larvae build cases out of sand or vegetation and live inside Breed in summer/fall https: //www. youtub e. com/watch? v=j. ID 1_Gwxi. E 0 149

Subphylum Hexapoda: Class Entognatha Order Collembola: springtails https: //www. youtube. com/watch? v=Ow. OL-MHc. Q 1 w • Closely related to insects but in a different class! • Very small (couple mm) • Extremely abundant in damp soil • Direct development (no larval stage) • Springing organ folded under the abdomen – called furcula https: //www. youtube. com/watch? v=j. Wcmy 84 P__0 Recently discovered cave sp. 150