Crustaceans- Subgroup of Mandibulata Flashcards
Crustaceans are mostly aquatic or terrestrial ?
Aquatic
Give the defining feature of crustaceans
2 pairs of antennae
Give the larvae of crustaceans
Nauplius (swimming) larvae
Many swimming appendages on front of body
What are PLEOPODS ?
Appendages that carry eggs or are used for swimming
Smaller than Peropods
What are PEROPODS ?
Appendages used for movement and feeding
Can have claws
Describe the life cycle of a crustacean.
Egg is laid, hatches into N larvae, add segments posteriorly to give Zoea Larva before continuing to modify to adult form
Why are N larvae important ?
Next generation
Relied upon as a food source
Most crustaceans are dioecious or Monoecious ?
Dioecious, males and females
Give the major groups of crustaceans
Malacostraca
Maxillopoda
Branchiopoda
Xenocarida
How do you identify male and female in the malacostraca group ?
Location of Gonopore
Female= 6th thoracic segment
Male=8th throracic Segement
Give species within the malacostraca group.
Phyllocarids, stomatopods, Anomurans, Pericardia, Euphausiacea
What is a decapod ?
An organism with 5 large thoracic limbs, with smaller limbs for feeding
E.g. Stomatopods
Give the characteristics of a Maxillopoda
Fewer than 10 body segments
Give the 2 sub-groups of Maxillopoda
Copepods
Thecostraca- barnacle, Rhiz
What group does Rhizocephala belong and what does it do ?
Maxillopoda, Thecostraca
Parasite, stimulate decapods to eat rather than reproduce
Describe fertilisation in a barnacle
They are a sessile species
Hermaphrodite (M/F)
Males use groping penis to fertilise
Describe an adaption of barnacles to their habitats.
The further up the tidal zone, (more shallow) the shorter and stouter the penis to avoid predation by seagulls.
Give a species in the Branchiopoda group
Anostraca, Sea monkeys
Fully freshwater. dried eggs can be regenerated by being placed back into water
To what group do Remipedia belong ?
Xenocaridia,
They are found in caves in the transition between salt and fresh water.
