Phyla Onychophora and Arthropoda Click on picture to go to phylum Onychophora Arthropoda

Phylum Onychophora

Phylum Arthropoda Jointed exoskeleton of chitin Trachea Malpighian tubules Specialization of segments Systems

Arthropod Systems Integumentary Integumentary- one cell layer epidermis, secretes exoskeleton of chitin. Skeletal- jointed exoskeleton of chitin; must be molted for growth, very protective, but not supportative. Muscle Muscle- striated muscle and very complex for moving skeleton; hydrostatic. Digestive Digestive- complex and complete, mouthparts and gut modified for food source. Systems continue

Arthropod Systems continues Excretory Excretory - coxal glands; green glands; Malpighian tubules Respiratory Respiratory - book gills, book lungs, tracheae. Circulatory Circulatory- open with dorsal heart; circulatory not used to transport oxygen in many species. Nervous Nervous- Dorsal brain; ventral double nerve cord with ganglia each segment; most behavior innate. Systems continue

Arthropod Systems continues Endocrine Endocrine- most hormones neural in origin; molting controlled by hormones, ecdysone and juvenile hormone. Reproductive Reproductive Varied, mostly dioecious, usually sexual dimorphism; complex life cycles; usually adult and larva do not compete for food. Fertilization mostly internal Development Direct development Hemimetabolous (incomplete)metamorphosis Holometabolous (complete) metamorphosis. Systems continue

Phylum Arthropoda Subphylum- TrilobitaTrilobita Subphylum- ChelicerataChelicerata Subphylum- CrustaceaCrustacea Subphylum- Uniramia (not on this power point presentation) Return to systems

Subphylum Trilobita Extinct Return to Subphyla

Subphylum Chelicerata (key-lis-er-a-ta) Merostomata Merostomata Class: Merostomata (mer-o-sto-ma-ta)Merostomata (mer-o-sto-ma-ta) Limulus (horseshoe crab)Limulus (horseshoe crab) Pycnogonida Pycnogonida Class: Pycnogonida (pick-no-gon-I-da)Pycnogonida (pick-no-gon-I-da) Sea spiders Arachnida Arachnida Class: Arachnida (a-rack-ni-da)Arachnida (a-rack-ni-da) Spiders, tick,mites, scorpions etc. Phylum Arthropoda

Class: Merostomata Limulus Return to Chelicerata

Class: Pycnogonida Sea spiders Return to Chelicerata

Class: Arachnida Araneae Araneae Order: Araneae (a-ran-e-e)Araneae Latrodectus (black widow spider)Latrodectus Loxosceles reclusa (fiddle-back spider or brown recluse)Loxosceles Scorpionida Scorpionida Order: Scorpionida (scorn-p-on-Ida) Scorpionida Scorpions Opiliones Opiliones Order: Opiliones (o-pil-e-on-i-da)Opiliones Harvestmen or daddy longlegs Acari Acari Order: Acari (ac-kar-i)Acari Ticks and mites Pseudoscorpionida Pseudoscorpionida Order: PseudoscorpionidaPseudoscorpionida pseudoscorpions Return to Chelicerata

Order Araneae Spiders Loxosceles reclusa Latrodectus Return to Arachnida

Order: Scorpionida Scorpions Ventral Return to Arachnida

Order: Opiliones Harvestmen (daddy longlegs) Return to Arachnida

Order: Acari Ticks and mites female male Return to Arachnida

Order: Pseudoscorpionida About 2,000 species of false scorpions The largest species reaches a length of only 7 mm Return to Arachnida

Subphylum Crustacea MaxillopodaCirripedia MaxillopodaCirripedia Class: Maxillopoda (subclass Cirripedia)Maxillopoda (subclass Cirripedia) barnacles Malacostraca Class: Malacostraca Isopoda Isopoda Order: IsopodaIsopoda pill bugs Amphipoda Amphipoda Order AmphipodaAmphipoda Decapoda Decapoda Order: DecapodaDecapoda Cambarus (Procambarus) - CrayfishCambarus (Procambarus) BranchiopodaCrayfish dissection BranchiopodaCrayfish dissection Class: Branchiopoda Crayfish dissectionBranchiopoda Crayfish dissection Tadpole shrimp Return to Arthropoda

Class: Maxillopoda Subclass: Cirripedia Barnacles Gooseneck barnacles Acorn barnacles Return to Crustacea

Class: Malacostraca Order Isopoda pill bugs Return to Crustacea Order Amphipoda

Class Malacostraca Order: Decapoda Return to Crustacea

Crayfish Dissection Sex determination Crayfish appendages Mouth parts All appendages Crayfish Internal Return to Decapoda

Sex determination Female Male Crayfish dissection

Cambarus dissection internal Crayfish dissection

Cambarus dissection mouth appendages Crayfish dissection

Cambarus dissection All appendages Crayfish dissection

Branchiopoda Tadpole shrimp Return to Crustacea