Crustaceans and Arachnids

Arachnid Respiration What are their structure called that allow for atmospheric gas exchange? Where does the gas exchange occur?

· arachnids have structures called book lungs that are used for atmospheric gas exchange; Openings on the anterior abdomen allow oxygen to diffuse in and carbon dioxide to diffuse out

Opiliones (daddy long legs) What are they known for? What shape is there body, and why does it appear to be that way? What are three things that makes this spider different from other spiders?

· known for having extremely long legs compared to their body size. The connection between the cephalothorax and abdomen is wider, so that the body appears to be single Oval structure · no venom glands, no silk glands, and can swallow solid foods not only liquid

Arachnid Morphology do they have an exoskeleton? what is there prosoma called? and what is it?

· like all arthropods arachnids have an exoskeleton · cephalothorax (aka prosoma): a combination of the head and thorax

Eyes of Arachnids How many eyes? Compound or simple? What can they see? What type of spider has good eyesight?

· most spiders have eight to six eyes all of which are considered simple. Most spiders can only see the difference between light and dark but some jumping spiders have excellent eyesight

What are the four arachnid subgroups? Hint: spiders, daddy long legs, scorpions, and ticks/mites.

· order Araneae (spiders) · order Opiliones (Harvest men or daddy long legs) · order scorpions · order acari (ticks and mites)

Mites What's its subclass? Large or small? __,____ plan of the typical __ segments on arachnids. Can it occupy multiple niches? Are they parasitic?

· part of subclass acari · most are tiny (less than one millimeter) and have a simple, body plan of the typical two segments on arachnids · occupy a wide variety of niches, but are known for being parasites

Ticks What's it subclass? What does it feed on? Can it transmit disease? What habitat can it live in? What's an ecotome?

· part of the subclass arcari · external parasites, living by feeding on the blood of mammals, birds, reptiles, and amphibians. Can act as vectors of many diseases · range and habit: text need warm, humid climates because they require a certain amount of moisture to undergo metamorphosis. They prefer the area where a lawn meets the woods called ecotome

Negative and positive human interaction with spiders What are the names of two harmful North American Spiders? ___% of spiders suffer from arachnophobia? What are the benefits of spiders?

· species are dangerous to humans: loxosceles and Latrodectus · arachnophobia estimated that 40% suffers from this · benefits: natural pest control, food, possible medical applications

Crustacean: digestion They have a ____ tube as a digestive track. Some have a chitinized structure called the ___ ___, which serves as a grinding apparatus

- crustaceans have a simple tube as a digestive track. Some have a chitinized structure called the gastric mill, which serves as a grinding apparatus

Ecology of Crustaceans What niche does it belong to? What do they feed on? Are they primary or secondary consumer? Who feeds of crustaceans? What are benthic crustaceans important?

- crustaceans playing many important roles in aquatic ecosystem. Some or zoo plankton, tiny drifting animals that feed on tiny plants-primary consumer (phytoplankton). They are consumed by fish, Wales, seabirds, and other crustaceans - benthic crustaceans are important as decomposers

crustacean: eggs Where/ when are the eggs released? K or r selection? Most decapods carry the eggs attached to the _______.

- fertilized eggs are either simply released into the water, or carried the parent until they are ready to hatch (r selected). most decapods carry the eggs attached to the pleopods.

Anatomy of Ticks How's it different from arachnids? What is the anterior capitulum? What does the posterior idisoma contain? What is a hypostome?

- no segmentation like other arachnids. Have an anterior capitulum (mouthparts) and the posterior idisoma which contains the legs, digestive tract, and reproductive organs - the capitulum has a structure called the hypostome is a hollow tube like structure used for blood extraction

Crustacean: abdomen 1) What are pleopods? 2) What do crustaceans use in their cardioid escape reaction?

- pleopods aka swimmerts- small paddles on the underside of the admin that are used for movements and holding eggs - tail fan- composed of uropods and the telson; used for steering while swimming and in the caridoid escape reaction

Crustacean: respiration What is the purpose of gills and where are they located?

- since crustacean are mostly aquatic, they need gills, which take oxygen out of the water. Gills are located on the thorax or on the appendages.

Arachnid movement What is the purpose of hydraulic pressure? How does it help spiders?

- while arachnid possess muscles for flexing their legs, they lack extensors for straightening them out - spiders use hydraulic pressure to extend their limbs. This pressure allows spiders to display a wide range of movement, including running, swimming, and jumping

Crustacean Classification: 1) Branchiopods 2) Maxilliopods 3) Ostracods 4) Malacostraca

1) Branchiopds: fairy shrimp (sea monkeys), clam shrimp, water fleas, and tadpole shrimp. Mostly freshwater and feed on plankton or detritus 2) Maxilliopods: barnacles, copepods and branchiura (fish lice). Named because they feed on their maillae 3) Ostracods: seed shrimp 4) Mala costraca: includes decapos, stomatopods, euphausiids, and isopods

Crustacean: cephalothorax 1) Mandible 2) Maxillae 3) Compound eyes 4) Antenna 5) Antennal glands 6) Statocyst 7) Maxillipeds 8) Pereiopods

1) Mandible is a hard, short, happy projections on each side of the mouth. Used providing and chewing food. 2) Maxillae projections that hold food cold usually at least two pairs 3) Compound eyes-usually stopped: important for detecting movement 4) Antenna- two pairs, project out of the head for sense and taste 5) Antennal glands- two large inside had to take out metabolic waste from body fluids it's create your base of antenna 6) Statocyst- organ that senses gravity 7) Maxillipeds- feeding legs, appendages modified to function as mouthparts 8) Pereiopods- walking legs, chelipeds (pincers)

Feeding Practices for Crustaceans 1) Name the four appendages used for feeding 2) What are filter feeders, scavengers, predators, and parasites?

1) Many appendages for feeding: mandible,maxilla, chelipeds, amxillipeds (feeding particles vary) 2) a)filter feeders- strain suspended matter in food particles from water b)scavenger- scraps of dead Organism c) predator- mullusks are a favorite food of crustaceans d) parasites- small crustaceans on or inside fish

Besides the egg stage, the crustacean life cycle has three different stages: 1) Nauplis stage 2) Zoea larval stage 3) Post larval stage

1) Nauplis stage- defining link between all creations; organism only has a head and telson (no thorax or abdomen); has a single eye atop the head and three pairs of cephalic appendages that allow it to swim 2) Zoea larval stage- characterized by the use of thoratic appendages for swimming and a large dorsal spine 3) Post larval stage- characterized by the use of abdominal appendages for propulsion. Begins to look like the adult form

Crustaceans exhibit many symbiotic relationships: 1) Parasitism: 2) Mutualism: 3) Commensalism:

1) Parasitism: a) anchor worms and fish: anchor worms suck the flood out of fish b) cymothia exigua and fish: cymothia eats the food of the fish and eats the fish's tongue 2) Mutualism: a) Pistol shrimp and goby fish: p.s. maintains habitat and g.f. protects shrimp b) Decorator crab and sponges: d.c. use sponge as camouflage an sponge gets to move around and collect for food 3) Commensalism a) Emperor shrimp and sea cucumber: jumps on back of s.e. and gets a free ride b) Whales and barnacles: b gets food particles from the whale that it doesn't pick up

Characteristics of crustaceans 1) Where are they jointed? Do they have segmented bodies and an exoskeleton? 2) What are biramous appendages? 3) Terrestrial or aquatic? 4) What are the sizes? Are they parasitic? Most are ____ (live at the bottom of the ocean) but can swim.

1) arthropods so jointed appendages, segmented bodies, and an exoskeleton 2) biramous appendages: legs are split into two 3) nearly all aquatic, both freshwater and marine. Few can live on land, such as hermit crabs call isopods 4) ranges in size from microscopic to very large. All are mainly free living, some can be parasitic. Most are benthic (live at the bottom of the ocean) but they can swim. Some are sessile such as barnacles. Microscopic ones simply move by current such as krill

Arachnid: defense What are three different techniques spiders use to defend themselves?

1) spider coloration typically is camouflage that helps them blend with their most common background or provide disruptive coloration 2) they also have venom 3 some mimic other insects. Some spiders like tarantulas have uticating hairs

Diet and Feeding of Ticks 1) What does this phrase mean" ticks are obligates hematophages? 2) Some ticks take longer to find a host, but when they do they excrete ____ (an _____) to prevent clotting. 3) How do ticks find hosts? What is questing?

1) tick are obligate hematophages (hemato- bood and phages- to feed) needing blood to move from one life stage to the next 2) some ticks attach quickly, while others wonder looking for thinner skin. Once it finds a suitable location, it attaches and cut a hole in the host epidermis. Then insert it hypostome excrete (an anticoagulant) to prevent clotting 3) ticks find host by detecting animals breath or CO2 and body odors or by sensing body heat. DEET hides lactic acid; questing-specific position a tick takes to hold on in order to find a place to feed (uses front legs)

Anatomy of a crustacean 1) What are the two segments called? 2) What does the exoskeleton cover? Does it molt? 3) What is molting? What are somites?

1)two segments: cephalothorax (carapace: shield protects neck) and abdomen(pleon) 2) exoskeleton has hard outer covering that protects the organism, molts for growth (chitin) 3) molting is shedding previous exercising so new and larger exoskeleton is formed. Each segment is divided into somites which can bear appendages

Characteristics of arachnids: How many legs? How may appendages and what are they called? Do they have wings and antennae? What are the two segments called? Are they aquatic or terrestrial? Are they omnivores, carnivorous, or herbivores?

4 pairs of legs two additional pairs of appendages: chelicerae and pedipalps. no wings or antenna. 2 by segments called tagmata: cephalothorax and abdomen. Mainly terrestrial. Mostly carnivorous

Abdomen (aka opithosoma) What's in the abdomen? Where is the spinnerets located? What is the spinnerets purpose? What do scorpions have, and what is it called?

Contains many important internal organs, such as the digestive track, reproductive organs, and lungs. Located at the end of the abdomen or the spinnerets, the silk producing organs used to make webs. Scorpions possess in additional appendage attached to the abdomen called a telson

Crustaceans Taxonomy: kingdom, phylum, and subphylum

Kingdom: Animalia, phylum: anthropoda subphylum: crustacea

Arachnid Circulation How is the circulatory system similar to crustaceans? What is a spider's blood called? Where is the blood pumped?

Like most arthropods, spiders have an open circulatory system and a blood cavity. Spider blood is called hemolymph, and pumped through space is called sinus is by the heart, which is located in the abdomen

Pedipalps What is it similar to? Where is located? What are its three main purposes?

Like the CHELICERAE, pedipalps are part of the spider's mouth. Located between the chelicerae in the first pair of legs. 1) It acts like the antenna, following the spider to sense objects that it encounters. 2) For some spiders, pedipalps aid in capturing prey and feeding. 3)Used by male spiders to transfer sperm to female spiders

Arachnid: capturing prey What are three different type of webs built?

Most but not all spiders build webs. Many spiders are named after the webs they spent. 1) spiral orb webs 2) tangle webs AKA cobwebs 3) funnel webs. Many spiders use innovative ambush technique to capture their prey. Examples: Portia, bolas

Crustacean: mating system How do they reproduce?

Most crustaceans have separate sexes, though some are hermaphrodites. Parthenogenesis (no sperm from males)is also common in crustaceans

Give 3 spiders that have unique ambush techniques. Describe these techniques.

Net-casting spider: puts a small amount of webbing between its front two legs and grabs onto prey as it walks by. Bolas spider: has a singular thread of webbing with a stick substance at the end. It swings this string around and throws it at moths as they fly around the spider. Portia spider: is a jumping spider that can launch at its prey. It is also highly intelligent and can problem solve.

Pistol Shrimp: 1) order and family 2) description 3) distribution 4) diet 5) anatomical distinctions 6) behavior 7) life cycle 8) ecological role

Order and Family Name(s): Decapoda and Alpheidae Description: two claws (small and large). Doesn't have symmetrical pincers. Distribution: Distributed world wide, but can be found in tropical waters of Indo-West Pacific area. Diet : eat small invertebrates Anatomical Distinctions : Has one extremely large claw and one small claw. Behavior: Their claw when it closes makes a rapid closing sound, and this behavior is primarily a defense mechanism against predatory fish. They are known for burrowing into sand, mud, and gravel with their front claws. Life cycle: Eggs: sink to the bottom at the time of spawning. Egg is 1/64th inch. Nauplius: The first stage is the size of the egg and succeeding stages are slightly larger. Nail have limited swimming ability and usually are a part of the oceanic plankton Protozoa: 1/25 inch- 1/12 inch. Protozoa have undergone development of their mouth parts and abdomen has begun to develop Mysis: legs and antennae develop Postlarva: swimming lags have developed and they appear to be mini shrimp. Juvenile: growth is rapid similar to adults except they have a longer rostrum. Sub-adults: mini-adults Adults: shell on upper body Ecological Role (what niche does the specimen occupy in its ecosystem?): they play an important role in reef ecology

Japanese Spider Crab: 1) order and family 2) description 3) distribution 4) diet 5) anatomical distinctions 6) behavior 7) life cycle 8) ecological role

Order and Family Name(s): decapoda ad inachidae Description : looks similar to a spider, rounded body with stubby projections and long slim legs. Distribution : North Pacific Ocean border of Japanese islands of Konshu and Kyushu Diet: dead animal or plant matter sometimes live fish or invertebrates such as other crustaceans Anatomical Distinctions: extremely long legs Behavior: gentle and calm; unable to swim; scavenge for food Life cycle : Eggs-->Zoea→ Megalopa→ Juvenile→ Adult Crab Ecological Role: benefits a marine ecosystem by eating dead animal and plant material, and their strong claws open dead starfish and shellfish

Hermit Crab: 1) order and family 2) description 3) distribution 4) diet 5) anatomical distinctions 6) behavior 7) life cycle 8) ecological role

Order and Family Name(s): order is decapoda and families are paguridae and coenobitidae Description: invertebrates, have exoskeleton, ten jointed legs, left claw is for defense, small right claw for food and water, and two different size claws Distribution :occur in sandy- or muddy- bottomed marine waters and occasionally on land and in trees. They are distributed world-wide Diet: they eat pellet food, supplemented with vegetables and fruit Anatomical Distinctions: have different size claws, hard shell that protects the abdomen, eyes that move on stalks Behavior: the crabs crawl over each other by pushing contests. Both feeler fights and pushing contests are crab behavior, and feeler fights are for smelling each other. Life cycle: the female carries eggs for one month, eggs burst when in contact with water (zoeare stage). Zoea pass through 4-6 stages (40-60 days). Metamorphosis into a megalopa (hermit crab like). Juvenile crabs. Adult crabs then lay eggs. Ecological Role: they are scavengers helping to recycle energy back into the ecosystem (important to benthic community).

Chelicerae What are these for spiders? Where is it located? What is it used for? Does it has muscles?

These are essentially the spiders jaws. Located on the very front of the CEPHALOTHORAX. Tipped with fangs and filled with muscles. Main use is to hold prey while the spider inject venom

Why are ticks negative to humans? What three diseases can they transmit?

Ticks are implicated in the transmission of a number of infections caused by pathogens such as bacteria, viruses, and protozoa. infections include Lyme disease, Rocky Mountain spotted fever, and typhus which can be fatal. Tick bites don't usually lead to infection if the ticks are removed within 36 hours

examples of crustaceans

crabs, shrimp, lobster, barnacles, crayfish, krill

Crustacean: circulation What is a open circulatory system? How is the blood drawn into the heart?

crustaceans have an open circulatory system meaning that all their why is not contained within vessels. instead, blood is drawn into the heart through holes called ostia , then pumped out again to circulate through the tissues

Arachnid: cannibalism When do some spiders eat there own kind?

· Arachnids have been known to consume their own kind in special circumstances. They used the males after sex as prey.

Arachnid reproduction Do males have a penis? What do they do if they don't? What is the epigyne and pedipalps?

· Male spiders do not have a penis. Instead, they collect sperm on the pedipalps (help sense objects) and introduce this to the females epigyne (external genital sturcture)

Arachnid maternity: How many eggs can they lay? What is a group of eggs called? How do spiders show maternal care?

· Most spiders lay up to 3000 eggs and especially woven eggs SAC. Many spiders protect this fact by attaching them to their webs, hiding them in nest, or carrying them, either in there chelicerae or spinnerets · some spiders exhibit maternal care by caring the spiderlings on their backs

Taxonomy: Phylum, subphylum, and class?

· Phylum: arthropoda · subphylum: Chelicerata · class: Arachnida

Arachnid digestion What type of food do spiders eat? How does a spider liquidate its food?

· Spiders consume only liquid foods. Most spiders release digestive fluids into their prey. This food dissolves surprised internal tissues. Then the spider feeds by sucking the partially digested foods out