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Cloudina - correct answer ✔Late Ediacaran, global distribution, calcitic tube-
like structures (sometimes presenting growth rings), cnidarians, Originally
discovered in Namibia
Earliest poriferans - correct answer ✔World wide distribution of unconnected
spicules and sclerites
Old definition of Pcb-Cb boundary - correct answer ✔The presence of shelly
organisms
Trichophycus pedum - correct answer ✔Index fossil of the PCb-Cb (Nemakit-
Daldynian) boundary enigmatic trace fossils. it indicates a new burrowing
strategy for feeding
Latouchella - correct answer ✔First gastropod (Tommotian) Shell presents
the beginning of coiling
Yochelcinoella - correct answer ✔Gastropod (Tommotian) presenting the
first siphon.
Tommotian Fauna - correct answer ✔the oldest diverse skeletonized fauna
on Earth
Microcystis - correct answer ✔Enigmatic Tommotian fauna with sclerites to
protect from unknown smaller predators
, Archeocyathids - correct answer ✔Earliest reef builders (take the place of
stromatolites), only occur in the Cambrian, Calcitic, worldwide.
Trilobites - correct answer ✔Arthropods, global distribution, diversified
greatly during the Atdabanian. Chitinous (calcitic) carapace
Burgess Shale - correct answer ✔a Lagerstatte in BC from the middle-
Cambrian
Pikaia - correct answer ✔Burgess Shale. Oldest Cephalocordate. (Similar to
modern Branchiostoma) V-shaped segmentations/Notochord/no skull
Opabinia - correct answer ✔Snoo-Snoo. Burgess shale one of the earliest
predators. Worm-like, 5 eyes and proboscis-like mouth.
Anomalocaris - correct answer ✔Burgess Shale. Apex predator, global,
binocular (360) vision. Limbs were not segmented.
Wiwaxia - correct answer ✔Burgess Shale. Enigmatic: no clear head/tail,
covered in large amounts of spikes/plates (probably not calcitic)
Hallucigenia - correct answer ✔Burgess Shale. Worm-like but without body
segmentations and dorsal spines
Ayisheaia - correct answer ✔Burgess Shale. Intermediate between worms
and arthropods. Tube-like segmented limbs.
Cnidaria - correct answer ✔Ediacaran Phylum, organized in tissue grade, no
organs.