DPS Ammonite Posted October 6, 2019 Posted October 6, 2019 A few days ago I found a very productive fossil site in the Pennsylvanian Naco Formation in central Arizona. I went up to look at an interesting new track site in the Permian Coconino Sandstone NE of Payson that was found by a friend and is being studied by the prolific Spencer Lucas from New Mexico. Link The Naco Formation site that I just found, has the most diversity of sponges of any Naco site to date. It also has lots of large brachiopods. Photo 1 shows a 3.4881 × 10-18 light years (3.3 cm) long Composita subtilita brachiopod, the largest that I have seen. Photo 2: impression of exterior of a brachial brachiopod valve with spines now shown as holes (probably Exhinaria semipunctata). Shell about 5 cm wide. Photo 3: there were lots of Antiquatonia portlockiana brachiopods. This one is 5 cm across. Photo 4: impression of the exterior of a 3 cm brachiopod brachial valve. Note molds of spines below. Photo 5: this is the longest horn coral that I have ever seen from the Naco. It is 18 cm long. I am guessing that it is a Caninia sp. Photo 6: this is the largest “spiky ball sponge” that I ever have seen from the Naco. 1.7cm across. I only find them as singles in the rock or eroded out pieces that occur by the dozens in a small area. Literature hints that they might be sponges spicules. I am beginning to wonder if they are not an entire sponge or another creature altogether. I have yet to see a spicule that has crosspieces or ridges close to the center of the ball where the spikes attach. Photo 7: here is the pièce de résistance, a giant 10 cm Wewokella sponge that only a friend has found at another site and originally identified his as a coral. I said that his was a sponge. Wewokella have spicules with an average of 3 or 4 points unlike the Regispongia of similar appearance. Link Detail of above sponge. Note spicule shape. Photo 8: a 7 cm “dot sponge” of unknown affinity. They are somewhat common in the Naco. Photo 9: a small 1.5 cm disk shaped sponge with straight radiating spines. It might be a Belemnospongia. Photo 10: there are lots of flat chert masses that contain lots of straight sponges spines, probably from a single collapsed unidentified sponge. 4 My goal is to leave no stone or fossil unturned. See my Arizona Paleontology Guide link The best single resource for Arizona paleontology anywhere.
TqB Posted October 6, 2019 Posted October 6, 2019 Fantastic site, the sponges are superb and I've run out of superlatives for that Wewokella. Tarquin
Wrangellian Posted October 6, 2019 Posted October 6, 2019 Nice specimens. Is that a bryozpan on the 1st brachiopod?
RJB Posted October 6, 2019 Posted October 6, 2019 Quite the report I must say. Some really good photos and very good explinations to go along. RB
grandpa Posted October 8, 2019 Posted October 8, 2019 OK, so it's dinner time in Grandpa's house and I'm feeling quite hungry. So when I saw the title my mind read "NACHO knockouts". Anyway, that's my story and I'm sticking to it. All of the finds are just super. I especially like the “spiky ball sponge”. Even the color of this guy shouts "what a find!". Congratulations on finding this site! What date would work best for you, for me to come visit you. I'll open up my calendar. Seriously, my friend, great job.
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