081420b

 

New calcimicrobe, Aphralysia anfracta, recently described from the Chesterian of North Alabama, has now been found in a second outcrop of the same age, some tens of miles away from the type locality. This organism lived in the openings within mounds and reefs, encrusted larger objects, and also bound other components together. The new locality is the subject of current research and contains a moderately diverse fauna. Notice the characteristic corkscrew or sinusoidal form of some of the tubules of A. anfracta. Thin section photomicrograph, image 1 mm tall.

 

David C. Kopaska-Merkel, Douglas W. Haywick, and Richard Keyes, 2020, A new mound-building biota from the lower Carboniferous of Alabama: Journal of Paleontology online 20 Jan. 2020, DOI 10.1017/jpa.2019.103

 

 

051519b

Looking for ideas about the affinities of this microfossil (two different views of one specimen):

 5 mm wide field of view

6 mm wide field of view (two different views of a single specimen)

We are thinking either a sponge or an alga (or a microproblematicum often considered to be an alga). Lower Carboniferous of Alabama, thin section photomicrographs.

Any ideas will be gratefully received!

                                                                           Update

An educated opinion has been offered, that the mystery critter is a blue-green alga (cyanobacterium), probably related to Pseudohedstroemia. Cyanobacteria were important co-constructors of mounds and reefs throughout the Paleozoic and beyond.

A Mississippian carbonate mound thin section

What is it? Suggestions include a tubular calcimicrobe or encrusting foraminifer.