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Crinoid+

1. (Crinoid) Haeretocrinus wagneri
2. (Crinoid) Brabeocrinus christinae
3. (Crinoid) Stellarocrinus virgilensis
4. (Crinoid) Kallimorphocrinus lasallensis
5. (Asteroid) Asteroid indet.

• Pennsylvanian
• LaSalle Limestone, Bond Formation
• Pontiac, Illinois, USA

Size: 12 cm crown for the Haeretocrinus

1. Haeretocrinus wagneri is a large and spectacular crinoid, dwarfing the rest of the Pontiac crinoid fauna. This species exhibits gracefully long, rounded, bi-endotomously branching arms that are constructed as to never be apposed to each other, as well as a recurved nodose anal sac (though relatively small and typically obscured by the arms). It also maintains the "primitive" cladid crinoid arrangement of three anal plates in the cup and uniserial pinnulate arms.

4. In contrast to Haeretocrinus, this is a very small and diminutive form measuring just 1-2cm. More notably, it shows the bizarrely simplified features of certain disparid crinoids, with an unequal number of unbranched arms per ray; some with two and some with one. This is the only disparid among the Pontiac crinoid fauna.

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