Crustaceans - PowerPoint Presentation

Slide1

Crustaceans

Video:

https://www.youtube.com/watch?v=3vENk9QPp4MSlide2

Crustaceans

All Arthropods have:

Exoskeleton

Jointed legs

Source: https://www.thoughtco.com/subphylum-crustacea-crustaceans-1968439Slide3

Crustaceans BasicsCrustaceans are ArthropodsAnimal KingdomPhylum Arthropoda

Subphylum CrustaceaThe name Crustacean comes from crusta meaning “crust” or “hard shelled ones”, due to the hard body armor typical of these animals

Most crustaceans live in the ocean and filter feed, scavenge, are predatory, or parasitic

However, some live in freshwater and others are terrestrial Slide4

Known Crustaceans

The most well-known crustaceans include:

Lobsters

Crabs

Shrimp

Crayfish/CrawfishSlide5

Crustaceans Physical CharacteristicsCrustaceans have four body parts:EyesAntennae

MouthpartsSwimmeretsAlthough it is typically classified as three (head, thorax, abdomen) or two (cephalothorax and abdomen)Slide6

Crustaceans Physical Characteristics (continued)All crustaceans have four antennae (only arthropod to have four antennae)Large

SmallCrustaceans do not have a heart but rather have an open circulatory systemThey have compound eyesSlide7

Crustacean ReproductionTypically reproduce sexually and fertilize externally but they are some species which regularly reproduce asexuallyEggs are held in brood chambers attached to the abdomen, or attached to abdominal appendages

Most crustaceans have a larvae which is unlike the adult and so must undergo metamorphosisHowever, crayfish develop directly without a larvae form Slide8

Crustacean PopulationThere are more than 800 families and over 40,000 speciesSome species live on land but 99% live in some type of water, either fresh or saltwater

Found in all different sizes, from a few inches to 10 feetSlide9

HistoryCrustaceans first appeared around 600 million years agoFossils of over 2,000 species have been foundSlide10

Main Crustacean ClassesBranchiopods – mostly small, freshwater animals that feed on plankton and detritus

Remipedia – blind crustacean found in coastal saline aquifersCephalocarida – horseshoe shrimp

Maxillopoda

– include barnacles and copepods (most abundant type of crustacean)

Copepoda

– fish lice

Pentastomida

– tongue worms

Ostracoda

– sometimes known as seed shrimp

Malacostraca – includes the most well-known crustaceansIncludes lobsters, crabs, crayfish, shrimp, krill, and woodlice Slide11

Malacostraca

Largest and most diverse class of Crustacea with over 20,000 species

Typically have a head with 5 fused segments, a thorax, with 8 segments, and an abdomen with six segmentsSlide12

Order IsopodaThis order includes pill bugsThese are the only truly terrestrial crustaceansSlide13

Order AmphipodaMarine, freshwater, and terrestrial formsAmphipods resemble isopodsSlide14

Order Euphausiacea

Contains 90 species

Includes planktonic kelp, baleen whales main food source Slide15

Order DecapodaAll Decapods have 5 pairs of walking legs and typically a pair of front pinchers

LobstersLobsters are cold blooded, meaning their body temperature depends on the temperature of the water

Most lobsters are nocturnal

Largest lobster ever caught was 44 pounds

They may live to be 100 years old

Come in a variety of colors and textures

Due to its abdominal flexors and shape of its tail, lobsters can dart backward in the water if needed to escape possible predators

Image: 22 pound lobsterSlide16

Order Decapoda (continued)Crabs

There are about 4,500 different kinds of crabsCrabs have well developed senses that help them find food and stay away from predatorsCrabs have three sets of jaws which help them crush food into tiny pieces for easy digestionSlide17

Crayfish BasicsAlso called crawfish or crawdad, interchangeablyConsidered close cousins of lobster, crabs, and shrimp

Lobster, crab, and shrimp live in salt waterCrayfish live in freshwater, in lakes and streamsThey are found in every continent except Africa and Antarctica

More than 230 species live in the US

New species are discovered every year Slide18

Crayfish Facts

They are NOT fish

Although they breathe with gills, they can stay out of water as long as their gills stay wet

Have five pair of legs

4 pair are used for walking

One pair is a set of pinchers used to grab things, especially food and for diggingSlide19

Crayfish GrowthTheir exoskeleton does not growWhen they get too big for their shell, they molt and break out of their old shell

At this time, they are very vulnerable to predators until their new shell hardensThey will molt many times throughout their lifeThey can also regenerate lost body parts Slide20

Crayfish Diet

They hunt for food at night

Eat almost anything small

- They clean up stream and lake beds

- Eat decaying plants and animals Slide21

Crayfish Sensing

Eyes are located on stalks that can move around

In front of the two eyes are two sets of feelers or antennae

One set is long

The other set is short

The antennae are covered in tiny hairs which help them touch, taste, and smellSlide22

Crayfish Reproduction

Crayfish lay eggs

Females lay the eggs and crawls into a hiding place to protect them

When the eggs hatch, they stay stuck to the mother’s tail until ready to swim of their ownSlide23

Crayfish Predators

Predators of crayfish include racoons, otters, mink, fish, turtles, some birds, and people

Crayfish hide under rocks or burrow into mud

They can defend themselves with their claws

Can swim backwardSlide24

Shrimp

There are over 2,000 different species of shrimp worldwide

Range in size from a fraction of an inch to 9 inches long

Shrimp are eaten by many animals including many fish, birds, octopi, squid, cuttlefish, and people

Mutualism: some shrimp live on anemones and keep them clean in return for protection Slide25

Maxillopoda

Include barnacles in the subclass

Thecostrae

.

These are mostly sessile crustaceans

Feed by extending legs through calcareous plates to filter feed

Barnacles are hermaphroditic

Some lack gills (

Branchiura

Subclass)

Ectoparasites

of marine and freshwater fishRange from 5-10 mm long Video: https://www.youtube.com/watch?v=kAzMhI7SEN8Slide26

Endoparasites such as tongue wormsVideo: https://www.youtube.com/watch?v=ppEoQ9U8kQ8

Infect respiratory systems of vertebrates, mostly reptiles but occasionally mammals, and airsacs

of birds

Range from 1 to 13 cm in length Slide27

Remipedia

Genetic studies show they are the crustacean most closely related to insects and are most primitive form of crustacean

Many even resemble many species of aquatic insect larvae

Only 10 described species

All known species are found in caves to the sea

Have between 25 and 38 segmentsSlide28

OstracodaOften have short bodies and lack appendagesMany species are parasitic

Enclosed in a two-part carapace and look somewhat like a clamTypically around 1 mm but can be up to 30 mm in length

Can be found on the sea floor or in freshwater habitats

Also found in humid forest soils

Video:

https://www.youtube.com/watch?v=8xEMhwvNO5sSlide29

Cephalocarida

Only 12 described benthic species

Live in coastal bottoms from intertidal zones to 300 m deep

Lack eyes, a carapace, and abdominal appendages

Hermaphrodites: Discharge eggs and sperm from same duct

Referred to as horseshoe shrimp

2-4 mm long

No fossil records found

Video:

https://www.youtube.com/watch?v=jwaUCwg3zx8Slide30

Branchiopoda

Class characteristic is that they have legs, called

phyllopodia

, that serve as respiratory organs. These legs may be used for filter feeding and locomotion.

Branchiopoda

species are mostly freshwater species Slide31

Branchiopoda (continued)Includes Order Anostraca

(Fairy and brine shrimp), Order Notostraca (Tadpole shrimp (triops

)), and

Diplostraca

(water fleas)

About 800 species of brine shrimp alive today

Video:

https://www.youtube.com/watch?v=VmfN4l-MolI

Video:

https://www.youtube.com/watch?v=g-Uq2fl3duQ

Anostraca

– Do not have a carapaceNotostraca – Carapace forms a large dorsal shield. Tadpole Shrimp are a living fossil, similar to horseshoe crabs, at close to 400 million years old, mostly unchanged for the past 250 million yearsDiplostraca – Carapace encloses entire body but not head. This includes the water flea and is the most diverse order of all the brachiopodsSlide32

Diplostraca - Water FleasWater fleas have are over 600 different recognized species Present in almost all inland aquatic habitats but are rare in the oceans

Most are only 0.2 to 6.0 mm longHave a single median compound eye

Video: Daphnia Heart Beat:

https://www.youtube.com/watch?v=M4wCq-yMj_wSlide33

Water Fleas (continued)Mostly asexual but can reproduce sexually. During sexual reproduction, resting (dormant) eggs are produced which allow the species to survive harsh conditions such as cold and desiccation

Males are only produced when unfavorable conditions ariseSince they are planktonic and therefore the base of the food chain, they are frequently used as an indicator of toxic conditions, observed by whether or not they reproduce and/or survive a given aquatic environment.

Video: Daphnia Heart Beat Explanation:

https://www.youtube.com/watch?v=ibDwYghgb2k

Video: Daphnia Babies:

https://www.youtube.com/watch?v=b7UFjsAYr3Y

Video of Lab Procedures:

https://www.youtube.com/watch?v=HhOUwlOdxkA