AMONG MY TRILOBITES


THE DEVONIAN PART 1

LICHIDA, CORYNEXOCHIDA,  PROETIDA AND HARPETIDA

The Devonian period was named for  Devon, which is a county in southwestern England.  Devon is not Welsh, but is separated from Wales by a narrow channel.  The Devonian began 413 million years ago and ended 365 million years ago.  While the land was starting to grow forests, some trilobites were forming extravagant spines, the function of which is still mysterious.  Notice the similarity between some of the trilobites from Morocco and their North American contemporaries.  While trilobites probably developed their wildest forms during the Devonian, their diversity was rapidly diminishing.


TO LEARN MORE ABOUT EACH ORDER OF TRILOBITES, CLICK ON
IT'S NAME.  THIS WILL TAKE YOU TO SAM GON'S WEBSITE FOR A
DESCRIPTION.  USE YOUR BROWSER'S BACK BUTTON TO RETURN
TO THIS PAGE.
LICHIDA ORDER


Superfamily: Lichoidea

 

5 cm total length  Al-Nif, Morocco

   

2.5 cm body, 3.8cm total  Al-Nif, Morocco

    

2.5cm  Hamar L'Aghdad limestone;  Djebel Issoumour area, Atlas Mountains, Morocco

Superfamily: Odontopleuroidae
Family: Odontopleuridae

2.5cm body, 4.9cm total  Djebel Oufhaten, Morocco

 

 

    

3.4cm total, 1cm spines L'Hafira, Morocco

 

3cm body  3.7cm spines Al-Nif,  Morocco

1.6cm body 2.2cm spines Cravat member, Bois D'arc formation,Clarita, Coal County, Oklahoma

5.2cm total  Ouijida, Morocco

 

2.7cm body, 6cm total  Haragan formation;
Coal County, Oklahoma


 

CORYNEXOCHIDA ORDER

Suborder:  Illaenina


Family: Styginidae(=Scutelluidae)



5cm Djebel Oufhaten, Morocco

6.2 Al-Nif, Morocco

Notice the terrace lines.  The eye is holochroal with a cornea rather than separate lenses.

There is a close-up of this eye on the last page along with several examples of the  schizoachroal type.

 

 

  

4cm  Al-nif, Morocco

 

6cm  Al-nif, Morocco



 
 

PROETIDA ORDER


Superfamily:  Proetoidea
Family: Proetidae

3cm  Hamar L'Aghdad limestone;  Djebel Issoumour area, Atlas Mountains, Morocco

  

1.7cm  Centerfield Limestone, Ludlowville formation, Hamilton, Livingstone County, New York

  

2.5cm  Hamar L'Aghdad limestone;  Djebel Issoumour area, Atlas Mountains, Morocco

2.3cm   Morocco


Family: Tropidocoryphidae

tropido

2 cm  Hamar Laghdad, Al-Nif, Morocco
Superfamily:  Aulacopleuroidea
Family: Aulacopleuridae
 

2.4cm  Hamar L'Aghdad limestone;  Djebel Issoumour area, Atlas Mountains, Morocco

  

3.5cm (including spine)  Hamar L'Aghdad limestone;  Djebel Issoumour area, Atlas Mountains, Morocco

     

1.4cm  Cravat member, Bois D'Arc formation,  Clarita,  Coal County, Oklahoma

     

9mm Cravat Member, Bois D'Arc formation; Coal County, Oklahoma

2 cm (including spine) Haragan Formation, Cravat member, Bois D'Arc formation,  Clarita,  Coal County, Oklahoma



 
 

HARPETIDA ORDER


Suborder:  Harpina
Family: Harpididae

5cm  Al-Nif, Morocco


   

To see the  Home Page

To see the   Cambrian Period Part 1: Agnostida and Redlichiida

To see the   Cambrian Period Part 2: Ptychopariida

To see the   Cambrian Period Part 3:  Asaphida, Corynexochida and Friends
To see the   Ordovician Period Part 1 Asaphida
To see the    Ordovician Period Part 2  Lichida, Phacopida, Corynexochida,  Ptychoparidia and Proetida
To see the   Silurian Period
To see the   Devonian Period Part 2:  Phacopida.
To see the   Carboniferous Period, the Permian Period, some Trilo-trivia and Links