Day 15 Arthropoda
Phyla Arthropoda
(Jointed Foot)
Arthropods are the largest animal phylum on the planet with more than a million species
-3 out of 4 animals on the planet are arthropods
-The largest group of arthropods are the insects yet there are not many insects in the sea
-The largest group of arthropods in the oceans are the crustaceans
Arthropod Characteristics
-Segmented body
-Bilaterally symmetrical
-Jointed appendages
-Exoskeleton- made of chitin
-Molt their exoskeleton to grow
Sub Phyla Crustaceans
-68,000 known species but maybe as many as 150,000 undescribed species
-Most are marine
-Crustaceans have two pairs of antennae, most have gills, their chitinous exoskeleton is usually hardened with calcium carbonate, and they have many legs.
Crustaceans have many different types of appendages
-It is best to familiarize yourself with these terms now because they will be present throughout the arthropod phylum
-Cephalon - Head (has the maxillae)
-Maxillipeds - Feeding legs
-Thorax - Holds arms and legs also known as Pereon
-Pereiopods - Walking legs
-Abdomen - Back end of body also known as Pleon
-Pleopods - Swimming legs
-Uropods - Tail Legs
-Telson - Paddle like tail
Watch this video on the phyla Arthropoda. Create a box in your sketchbook, title it "The Phylum Arthropoda" and take notes, write down interesting things that you learn from the video and include an image in your sketchbook. Make sure you understand the characteristics of Arthropods and the differences between the different orders of crustaceans.
Crustacean Classes
Class Maxillopoda (Feed with their Maxillae)
-Maxillopods have
-5 Cephalic segments
-6 Thoracic segments
-4 Abdominal segments followed by a telson
Subclass: Copepoda (Oar Feet)
-Copepods are extremely abundant. One of the most abundant animals on earth
-Considered Plankton
-Use their mouth parts to filter food from water
-Can use their first pair of antennae to swim so they do not sink
-Some species are parasitic
Infraclass: Cirripedia (Curly Foot)
Common Name: Barnacles
-Are sessile
-Filter Feeders
-Live on rocks, whales, and crabs
-Many are very specific about the type of surface they live on
-Inclosed by heavy calcateous plates and can be easily confused for mussels
-Have Cirri- feathery filtering appendages
Class Malacostraca
Malacostracans have 20 body segments...there are a couple that have 21...but most of them, 20 BODY SEGMENTS!
Order: Amphipoda (Two Legs)
-Sometimes known as water fleas
-Can jump
-Beach hoppers
-Live on the sand eating dead seaweed
-There are freshwater and saltwater species
-Most of them are very tiny
-very hard to see
-Have sideways flattened bodies
-Some are parasitic
-Whale lice burrow into the skin of whales
-Over 5,000 species
Order: Isopoda (Same Legs)
-Are usually dorsoventrally flattened
-Pill bugs are common land isopods
-Most isopods are very small but there are some giant isopods in the ocean
-Legs that are similar to each other
-The sea louse or sea roach (not a roach) lives on shore and eats decaying seaweed
-There are also parasitic isopods
-Fish lice- Will eat the tongue of fish and replace it with themselves sharing the food that the fish eats
Order: Krill
(Order Euphausiids)
-Plankton
-Head is fused to some of the body segments forming a distinctive carapace
-Filter feeders
-Arctic
-Primary food for many whales, penguins, and some fish
Order: Stomatopoda (Mouth Foot)
-Common Name: Mantis Shrimp
(Not a true shrimp)
The mantis shrimp is a fascinating animal. Do some research on the mantis shrimp. Create a little section of your sketchbook to include information that you learn about the mantis shrimp.
Watch and enjoy this Deep Look video about the mantis shrimp. Create a box in your sketchbook, title it "Mantis Shrimp" and write down interesting things that you learn from the video and include an image in your sketchbook.
Watch and enjoy this Animalogic video about the mantis shrimp. Add any new information to your box titled "Mantis Shrimp" that you might have learned compared to the deeplook video.
Order: Decapoda
Shrimp, Lobsters, and Crabs
-More than 10,000 species
-Largest group of crustaceans
-5 pairs of legs (Pereiopods)
-First pair are usually claws or used for feeding
-3 pairs of maxillipeds for feeding
-Cephalothorax and abdomen
Common Name: Shrimp
This is an optional video about the pistol shrimp. The pistol shrimp can create a bubble hotter than the lava from a volcano. If you are interested in learning about the pistol shrimp, enjoy this video.
Common Name: Lobsters (Has two very large claws)
Common Name: Spiny Lobster (Does not have front two claws)
Common Name: Crabs (Tail is sealed or tucked under thorax)
Watch and enjoy this Johnathan Bird video.