041019c

Fecal-pellet grainstone dominated by the distinctive pellets of callianassid shrimp (the larger particles). Dolomitized Jurassic Smackover Formation, Alabama, thin-section photomicrograph. The pallets are trace fossils called Parafavreina ziczac. Generally, no fossils of the shrimp themselves are preserved, but their distribution is easily recognized from their pellets.