BIOL 3454 1nd Edition Lecture 20Lecture 10/29I. Phylum Nematomorphaa. Roots: Greet menatos (thread) and morpha (form)b. Horsehair worms c. About 320 species d. Worldwidee. Free living as adults and parasitic in arthropods as juvenilesf. 1m or smaller in lengthg. Anterior end rounded h. Posterior end rounded with 2-3 caudal lobesi. No circulatory, respiratory and excretory systemsj. Nerve ring around pharynx and midventral nerve cordk. Dioecious l. Gonads empty into cloaca through gonoduct eggs discharged into water in long stringsII. Phylum Kinorhyncha a. Roots: greek kinein (to move) and rhynchos (break)b. About 180 species c. Worldwide d. Intertidal to 8000m e. Live in sediment f. Head, neck and trunk regions g. Trunk has 11 segments h. Head has spines called scalids that function as locomotion, chemoreception and mechanoreceptioni. Body has chitinous cuticle, cellular epidermis and longitudinal epidermal cordsj. Cant swim, burrow in mud and anchor with spinesk. Digestive system complete l. Probosicis m. Pseudocoel filled amebocytes and organs with little fluid spacen. Pair of multinucleated soleonocyte protonephridium serves as excretory system o. NS in contact with epidermis and multilobed brainp. Separate sexes q. Paried gonads and gonoductsr. 6 juveniles stages s. Nonmolting adultIII. Phylum Priapulidaa. Roots: Greek priapos (phallus)b. Marine cold waterc. Live in sediment These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.d. Cylindrical bodies e. Burrowing and predaceous feeding on soft bodied invertebratesf. Body has an introvert, trunk and 1 or 2 caudal appendages g. Introvert has papillae and curved spines called scalids around mouthh. Trunk has 30 to 100 rings covered in tubercules and spines probably sensory i. Muscular pharynx straight intestine, rectum j. Nerve ring around pharynx and midventral nerve cordk. Amebocytes occur in body cavity l. Respiratory pigment called hemerythrin m. Separate sexes n. External fertilization o. Females brood embryos IV. Phylum Loriciferaa. Root: Latin lorica (corset) and Greek phora (bearing)b. Described in 1983 c. Tiny all have a protective case called a loricad. Live in marine gravel e. Body has 5 regions: mouth cone, head or introvert, neck, thorax, abdomen f. 9 circlets of scalids on introvert (locomotion and sensory)g. Body can retract into loricah. Pseudocoelomate or acoelomatei. Dioecious j. Larval phase called Higgins k. Life cycle benthic and pelagic V. Clade - Panarthropodaa. Arthropods and 2 allied taxab. Onychophora and tardigradac. Coelom reduced d. New cavity called a hemocoel e. Coelom mixed with blastocoel f. Lined by extra cellular matric not mesoderm VI. Phylum Onycophoraa. Roots: Greek onyx (claw) and pherein (to bear)b. Velvet or walking wormsc. About 70 species most in rainforest d. Most predaceous on insects, gastropods and annelidse. 500 million year fossil history with little changef. Cylindrical with no external segmentation except for paired appendagesg. Body studded with tubercules some with sensory bristlesh. Head with one pair of large antennaei. Clawlike mandibles j. Oral papillae that secrete slime for defensek. 14-34 pair of unjointed legs that are short and stubby and clawedl. Muscular body wallm. Each segment with legs has a pair of nephridia with a veicle, ciliated funnel, duct and nephridiopohore that opens at the base of each legn. Tracheal system for respiration o. Openings are spiracles, cannot close so are restricted to moist habitatsp. NS organized like a ladder – pair of ventral nerve cords with smaller nerves acting as steps q. Well developed eye r. Group hunting s. Dioecious t. Paired reproductive organs u. Some matrotrophic and some lecithotrophic VII. Phylum Tardigradaa. Roots: latin tardus (slow) and gradus (step)b. Water bears c. 900 species terrestrial and live in water film surrounding mossd. Share many characteristics with arthropodse. Cylindrical unsegemented body f. 4 pairs of stubby unjointed legs each with 4 to 8 clawsg. Nonchitinous cuticle molted atleast 4 timesh. Moth opens to buccal tune leads into muscular pharynx adapted for sucking i. Needlelike stylets pierce cells and suck out contents j. At junction of intestine meets rectum, 3 excretory glands and empty into digestive tube k. Most of body cavity a hemocoel l. No circulatory or respiratory system m. No swimming no circular muscles n. Crawl awkwardly o. Large brain with eyesp. Separate sexes q. Females are parthenogeneticr. Fertilize by cuticle piercing s. Some cement eggs into an object others leave them in the molted cuticle t. Indirect fertilization – male inserts sperm in eggs in molted cuticle u. Suspended animation i. Cryptobiosis metabolism barely perceptible ii. Can withstand harsh conditionsiii. Extreme temps, dehydration, radiation, strong chemicals, and can survive for