Arthropod CrustaceanPaula Martinez-Feduchi9B

Arthropod Crustaceanh) Arthropod

iii)Crustacean• Scientific name: Arthropoda Crustacea • Arthropoda: jointed feet• Crustacea: mandibulate aquatic

• 40,000 named species • Likely +100,000

• Life Expectancy:• Lobster: up to 50 yrs, max. 100 yrs• Shrimp: to 6 ½ yrs• Crabs: 1-3 yrs

Characteristics• Chitin exoskeleton • Strengthened w/ calcium salts

• Stalked eyes• Wax layer on exoskeleton• survive on land w/o loosing too much water

• Biramous appendages• 2 pairs of antennae

a. First pair--similar structure to insects’b. Second pair– pincer-like claws

Characteristics Continued• Molt--shed old exoskeleton• Segmented bodies--somites (segment)

• rigid or flexible • Pair of appendages near mouth--functions as jaw• Can be sessile (not moving) ex: barnacle• Live in:

• freshwater • Seawater• inland• brines- water w/ high salt concentration

• Carapace #9 enfolds trunk can:• split into valves • projects to form rostrum #8

Fossil Record• Cambrian period : 544 to 505 mya

a. Canadapsis b. Perspicaris

• Carboniferous period: 360 to 286 mya– all major groups except Eucarida• Examples:

a. Ostracoddab. Branchiopodac. Cirripediad. Eumalacostracae. Maxillopoda

Life Cycle1. Egg 2. Naupilus– head, unsegmented body, antennas,

mandible, 1 eye3. Zoea– segmented body, appendages, molts several

times4. Mysis/Megalopa–structures continue to form5. Post-Larval– legs for swimming & walking. Full

size & adult appearance6. Adult– after 1 yr, capable of mating

& reproducing

Reproductiona. Sexes separated• Change of sex during life • Sexual Reproduction

b. Hermaphrodites (male & female reproduction organs)• Males attach to interior of mantle cavity • fertilize eggs (barnacles)

• Ovaries contain sperm-producing parts beside eggs• Sexual Reproduction

c. Parthenogenesis– produce eggs that develop w/o being fertilized by sperm• Asexual Reproduction• Mechanically or chemically stimulated

Reproduction Continued• Sexual Dimorphism (diff. appearance male & female)• Males—smaller & parasitic--enter female genital tract• Males--clasping organs hold females

i. Females release eggs into water

ii. Carry eggs:• Sac on abdomen • pouch behind limbs• Between limbs• Eggs in strings– may be coiled

Diet and Digestive System

• Large--bottom-dwelling predators• Suspension feeders-- create water currents • feed on small organisms

• Carnivores, herbivores, scavengers and cannibals• Digestive tract--through length of body, can be coiled

Diet and Digestive System Continued

• Foregut a. simple tubeb. gastric mill-- ossicles (calcified plates)

a. move against each otherb. grind food

• Midguta. Before--setae (hair) filter

a. prevent particles to pass until certain sizeb. Differs in species

a. 1 or +1 diverticula (pouches)-- different processes• Hindgut

a. Shortb. Waste excreted through anus

Respiratory Systema. Gas exchange--through carapace (outer shell)

many blood vesselsb. Gills

a. Circulate water past gills--move themb. Blood flow in opposite direction than water:

a. extract more oxygen than in same directionc. Tracheal– tubules network brings oxygen, discharge

carbon dioxide

Circulatory System• Open circulatory system • Blood flows in sinuses (channels)• Many no heart

a. Blood in movement by blood pump or body movements• With heart

a. In blood sinus (cavity) or pericardium (membrane enclosing heart)

b. Connected by valvular openings--ostia• Primitive

a. Long tube w/ spiral musclesb. Spreads almost all of trunkc. 2 Ostias in each somite except last

Sensory System• Brain • Subesophageal ganglion--connected to nerve centers• Chain of ganglia through trunk • Nerve cord- pair of ganglia per somite

• Control appendages• Nerve connections w/ eyes & antennae

• Nerve ring around esophagus• Direct to brain

Sensory System

• Stalked eyes- better eyesight• Compound eyes- w/ pigment cells• expand or contract-- see in light intensities

• Statocyst• Balance & orientation• Change in orientation• statoliths (small granules) impact w/ setae at angles

• Setae--tactile hairs on body• movement in water & touch

• Chemicals on antennae & mouth• taste & smell

Bibliography• http://www.lessonsnips.com/docs/pdf/arthropods.pdf• http://www.globio.org/glossopedia/article.aspx?art_id=15• http://

www.enotes.com/arthropods-insects-arachnids-crustaceans-reference/arthropods-insects-arachnids-crustaceans

• http://www.woodbridge.tased.edu.au/mdc/Species%20Register/phylum_arthropoda_crustacea.htm

• http://www.blurtit.com/q106454.html• http://www.audioenglish.net/dictionary/class_crustacea.htm• http://www.wetwebmedia.com/marine/inverts/arthropoda/crustace.htm• http://bugs.osu.edu/bugdoc/Shetlar/462/462arthropods/Arthropods17.htm• http://zoology.muohio.edu/crist/zoo312/crustaceans.html• http://www.tafi.org.au/zooplankton/about/glossary.html• http://www.waterencyclopedia.com/Ce-Cr/Crustaceans.html#b• http://www.oceaninn.com/the-nature-preserve/crustaceans/• http://www.biology-questions-and-answers.com/phylum-arthropoda.html• http://www.britannica.com/EBchecked/topic/144848/crustacean/33810/The-respirator

y-system• http://www.uwlax.edu/biology/Zoo-Lab/Lab-08/Crayfish-External-Anatomy-2.htm• http://www.eoearth.org/article/Crustacea• http://

faculty.clintoncc.suny.edu/faculty/michael.gregory/files/bio%20102/bio%20102%20lectures/Respiratory%20System/respirat.htm

• http://archimer.ifremer.fr/doc/1989/acte-1486.pdf• http://www.ucmp.berkeley.edu/paleozoic/paleozoic.php• http://faculty.clintoncc.suny.edu/faculty/michael.gregory/files/bio%20102/bio%20102

%20lectures/circulatory%20system/circulat.htm