Ecdysozoa

Question 1

What are exuviae and what can they do?

Answer 1

Shedded moults that can distort the fossil record

Question 2

Define ecdysis

Answer 2

Moulting of the cuticle

Question 3

Describe Priapulida

Answer 3

Worm-like anatomy, invertible scaled-lined proboscis, circular brain surrounding gut

Question 4

Describe Nematoda

Answer 4

Pseudocoelomates, can have piercing stylet, can by pathogenic

Question 5

Describe Panarthropoda

Answer 5

Legs, segmented body, includes onychophoran (walking worms) and tardigrada

Question 6

Give an example of the most basal euarthropods

Answer 6

Lobopodians (legged worms)

Question 7

Give an example of a highly derived arthropod

Answer 7

Great appendage arthropods

Question 8

Describe Opabinia

Answer 8

Swimming appendages, compound eyes (looks like teletubbies hoover)

Question 9

Describe bivalved arthropods

Answer 9

Specialised biramous appendages

Question 10

Describe anomalocaris

Answer 10

Raptorial oral appendages around circular mouth (rather than on body like modern arthropods have)

Question 11

Define arthrodisation

Answer 11

Stepwise acquisition of euarthopod characteristics on euarthropod stem-lineage

Question 12

Order euarthropoda, most basal to most derived

Answer 12

Lobopodia, anomalocaris, bivalved arthropods, great appendage arthropods