Ancient Species -
Starfish & Sea Urchins

Blastoids and crinoids are echinoderms which have stalks and keep their mouths pointed upward. Sea urchins and starfish are echinoderms with their mouths pointed down and no stalks.

The earliest ancestors of the starfish appeared in the Cambrian Period (590 to 303 million years ago). They were shaped like flattened balls and ate things lying in the mud. By the Ordovician Period (505 to 434 million years ago), they had evolved into a plump star shape with five or more points. Each point contained a branch of the stomach but there was only one mouth in the center.

Early sea urchins resembled melons covered in spines. In some, the spines were needle-like; in other, they were quite thick. All sea urchins have five double rows of plates. In modern sea urchins, these plate contain holes through which tubular feel , called ambulacra, extend.

 

Starfish & sea urchin fossils now available (at eBay):

Click on an item to view details and, if you wish, bid.

83mm Starfish Fossil Geocoma Corinata Ordovician Period Decorative Stone Morocco

AU $37.65
End Date: Monday May-20-2019 20:14:57 EST
Buy It Now for only: AU $37.65
Buy It Now | Add to watch list

150g Starfish Fossil Mineral Geocoma Corinata Ordovician Period Stone - Morocco

AU $39.05
End Date: Monday May-20-2019 20:14:55 EST
Buy It Now for only: AU $39.05
Buy It Now | Add to watch list

GEOLOGICAL ENTERPRISES Silurian very rare fossil starfish Australaster gigan

AU $60.11
End Date: Monday May-20-2019 1:01:06 EST
Buy It Now for only: AU $60.11
Buy It Now | Add to watch list

83mm Starfish Fossil Geocoma Corinata Ordovician Period Decorative Stone Morocco

AU $37.68
End Date: Sunday May-19-2019 23:44:48 EST
Buy It Now for only: AU $37.68
Buy It Now | Add to watch list

150g Starfish Fossil Mineral Geocoma Corinata Ordovician Period Stone - Morocco

AU $39.08
End Date: Sunday May-19-2019 23:44:38 EST
Buy It Now for only: AU $39.08
Buy It Now | Add to watch list

100% Natural Fossil Sea Urchin (Cretaceous Period)

AU $35.00 (0 Bids)
End Date: Friday Apr-26-2019 22:04:51 EST
Bid now | Add to watch list

Fossil Sea Urchin Lot of 2 Specimens for Display or Jewelery Craft 14

AU $13.97
End Date: Thursday May-9-2019 17:02:19 EST
Buy It Now for only: AU $13.97
Buy It Now | Add to watch list





FAQs | About Us | Contact

Copyright © Peter Thorogood

Web design by Peter Thorogood