Crustaceans- Subgroup of Mandibulata

Question 1

Crustaceans are mostly aquatic or terrestrial ?

Answer 1

Aquatic

Question 2

Give the defining feature of crustaceans

Answer 2

2 pairs of antennae

Question 3

Give the larvae of crustaceans

Answer 3

Nauplius (swimming) larvae

Many swimming appendages on front of body

Question 4

What are PLEOPODS ?

Answer 4

Appendages that carry eggs or are used for swimming

Smaller than Peropods

Question 5

What are PEROPODS ?

Answer 5

Appendages used for movement and feeding

Can have claws

Question 6

Describe the life cycle of a crustacean.

Answer 6

Egg is laid, hatches into N larvae, add segments posteriorly to give Zoea Larva before continuing to modify to adult form

Question 7

Why are N larvae important ?

Answer 7

Next generation

Relied upon as a food source

Question 8

Most crustaceans are dioecious or Monoecious ?

Answer 8

Dioecious, males and females

Question 9

Give the major groups of crustaceans

Answer 9

Malacostraca
Maxillopoda
Branchiopoda
Xenocarida

Question 10

How do you identify male and female in the malacostraca group ?

Answer 10

Location of Gonopore
Female= 6th thoracic segment
Male=8th throracic Segement

Question 11

Give species within the malacostraca group.

Answer 11

Phyllocarids, stomatopods, Anomurans, Pericardia, Euphausiacea

Question 12

What is a decapod ?

Answer 12

An organism with 5 large thoracic limbs, with smaller limbs for feeding
E.g. Stomatopods

Question 13

Give the characteristics of a Maxillopoda

Answer 13

Fewer than 10 body segments

Question 14

Give the 2 sub-groups of Maxillopoda

Answer 14

Copepods

Thecostraca- barnacle, Rhiz

Question 15

What group does Rhizocephala belong and what does it do ?

Answer 15

Maxillopoda, Thecostraca

Parasite, stimulate decapods to eat rather than reproduce

Question 16

Describe fertilisation in a barnacle

Answer 16

They are a sessile species
Hermaphrodite (M/F)
Males use groping penis to fertilise

Question 17

Describe an adaption of barnacles to their habitats.

Answer 17

The further up the tidal zone, (more shallow) the shorter and stouter the penis to avoid predation by seagulls.

Question 18

Give a species in the Branchiopoda group

Answer 18

Anostraca, Sea monkeys

Fully freshwater. dried eggs can be regenerated by being placed back into water

Question 19

To what group do Remipedia belong ?

Answer 19

Xenocaridia,

They are found in caves in the transition between salt and fresh water.