Posts Tagged ‘cnindaria’

Devonian Tabulate Coral

February 4, 2011

A few years ago, I was working a project in northern Jefferson Co. Ky. that was in the preliminary stages of development. As such, the area had been stripped of vegetation leaving a vast field of regolith that was a mud pit when it rained… sticky clayey mud. But, those rains also uncovered thousands of silicified fossils that littered the ground of the project.

One of the larger pieces that I picked up was a head of the tabulate coral Alveolites. It was fossilized as silica replacement that is common of many fossils in the Jeffersonville Limestone.

A view of the base of the colony

The top of the colony

The individual corallites are about 2mm diameter.

Hiding in the Bushes?

April 11, 2010

Kevin Bylund’s last post over at Ammonoidea included a photograph of some very small gastropods(<1mm). It had me wondering… were they proto-gastropods(juveniles), or were the critters adult forms? I'm not much on that new stuff(well, kind of new, they are early Mesozoic).

Similarly sized proto-gastropods are common in some beds of the Lexington Lm(late Middle Ordovician-early Late Ordovician). They are usually found intimately associated with sponges and corals. Apparently, the little critters were seeking protection from larger predators or currents???

Any thoughts? Have you found similar associations?

The tabulate Foerstephyllum sp. on which two species of proto-gastropods were found.

Platycerid and murchisoniid proto-gastropods-mag x30(most of the gastropods from the unit are Cyclonema varicosum and Loxonema sp., though an occasional eotomarid or tergomyid will show up). Close up of above.

A Solenopora sp. sponge with murchisoniid proto-gastropods(see above).

Again, a close up of the above(note the probe for scale).