![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-12024-C.-ulrichi-x5.jpeg)
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-12024-C.-ulrichi-x5-1024x787.jpeg)
CryptolithoidesCC BY-NC-ND 4.0
Cryptolithoides
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/Mesotaphraspis-x15-d.jpg)
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/Mesotaphraspis-x15-d.jpg)
MesotaphraspisCC BY-NC-ND 4.0
Mesotaphraspis
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-12034-x8-d.jpg)
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-12034-x8-d-1024x601.jpg)
CryptolithusCC BY-NC-ND 4.0
Cryptolithus
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-12123-x8.jpg)
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-12123-x8-1024x591.jpg)
AchatellaCC BY-NC-ND 4.0
Achatella
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/GHQ-cr-4-x6.jpg)
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/GHQ-cr-4-x6-921x1024.jpg)
CalyptaulaxCC BY-NC-ND 4.0
Calyptaulax
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/Frencrinuroides-x8-0042.jpg)
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/Frencrinuroides-x8-0042-1024x611.jpg)
FrencrinuroidesCC BY-NC-ND 4.0
Frencrinuroides
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/Calyptaulax-x6.jpg)
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/Calyptaulax-x6-1024x794.jpg)
CalyptaulaxCC BY-NC-ND 4.0
Calyptaulax
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/Frencrinuroides-x8-pyg.jpg)
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/Frencrinuroides-x8-pyg-1024x883.jpg)
FrencrinuroidesCC BY-NC-ND 4.0
Frencrinuroides
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-11864-x5-11.jpg)
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-11864-x5-11-1024x897.jpg)
AnataphrusCC BY-NC-ND 4.0
Anataphrus
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-11785-x3-01.jpg)
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-11785-x3-01-1024x877.jpg)
IsotelusCC BY-NC-ND 4.0
Isotelus
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-11864-x5-12.jpg)
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-11864-x5-12-1024x804.jpg)
AnataphrusCC BY-NC-ND 4.0
Anataphrus
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-11778-x3-02.jpg)
![](https://samnoblemuseum.ou.edu/wp-content/uploads/2017/08/OU-11778-x3-02-1024x1017.jpg)
IsotelusCC BY-NC-ND 4.0