San Antonio/glen Rose: Coral? Burrows?

[Piedras_de_Tejas]

Here are some pics of an odd tube-like fossil i found on my first trip to the glen rose formation. if it helps, i found them in a layer packed with bivalve casts just a foot or two above a layer full of leptosalenia and heart urchins. I'm not sure if they're coral, burrows, or some type of stem, but I haven't a clue Anyone recognize these? My guess right now is some type of burrow...

[Auspex]

Your guess is mine as well. The largest one shows the pellet-texture of shrimp burrows.

[Piedras_de_Tejas]

Thanks Auspex, don't think i've ever found these before.

[erose]

Burrows are fairly common in the Glen Rose. Auspex was right to point out the "pellet" texture in that large one. Crustaceans like ghost shrimp(?) sometimes made little balls of mud to strtengthen their burrows if the substrate was soft. Thye name for that type of ichno (trace) fossil is Lophiomorpha. Most burrows are hard to pin down to who made them but Lophiomorpha is easil;y identified as being from a crustacean since those critters still do this today.

[Plax]

or Ophiomorpha? Also used to b called Halymenites if it's the same trace I'm thinking of

[kiwi2929]

definitely burrows, nice ones too!

[erose]

or Ophiomorpha? Also used to b called Halymenites if it's the same trace I'm thinking of

Yes, duh. Phat finger typing... Ophiomorpha

[Plax]

actually thought it might have another name, wasn't correcting

[Piedras_de_Tejas]

Thanks for all the great info y'all . Come to think of it i've encountered semi-cylindrical traces like this before, but i never knew what they were until the texture on these spiked my interest enough to make this post. Common or not, i haven't collected anything similar, so they are joining the rest of my "keep".