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How should I prep this 6 cm wide crushed conulariid that is covered in a massive bryozoan and is from the Pennsylvanian Naco Formation of Arizona? It is only the second one that I have found. The matrix is a shaley limestone and is full of bedding cracks. Flakes are falling off either side of the fossil. I would like to take most of the matrix off the back side by hammer and chisel along a bedding plane 1-2 inches below. I can make any thickness of Butvar B-76 solution in acetone. I am afraid that covering the conulariid with Butvar might not hold it together if I try to split the rock and inch or so below the fossil.

What is this cross section of a 5 cm tall gastropod from the Pennsylvanian Naco Formation of Arizona? The photo of whole gastropods that are similar and are found in the same formation at the Kohl’s Ranch site. Photo by Caty Sandoval. What are these? This may help (I have a good guess): https://www.dallaspaleo.org/resources/Documents/PGUPFT 2a Mollusca first half.pdf

This fossil with faint triangular outline is covered in a bryozoan was found in the Pennsylvanian Naco Fm. near Kohl’s Ranch. Is it a flattened conulariid? 2 cm coin for scale.

Please help ID these Pennsylvanian Naco Formation trace fossils from central Arizona. Help Chris. @Arizona Chris Are the 1 cm wide chevron tracts in photo 3 Cruziana from trilobites? What are the 2.5 - 3 cm long teardrop shaped features in photos 1 and 2? What are the 2.5 - 3 cm long teardrop shaped features in photos 1 and 2? What are the elongated traces 3.5 to 4.5 cm long with length parallel marks in photo 4? From crustaceans?

I have found many Pennsylvanian sponge roots in an isolated area of the Naco Formation near Payson, Arizona. The sub parallel root fibers range in size from 0.2 to 1.2 mm in diameter. The roots are often found growing/covering crinoid columnal sections. Near Pine and at my site the roots are found where Chaunactis olsoni sponges are the most common, but not the only sponge species present. Now I need to find a sponge with roots attached to ID the species of the roots. It is unknown if the silicified roots were originally silica or calcite. I noticed that there are grooves from and matching the diameter of the roots in originally calcitic crinoid columnals and head pieces. What caused these grooves? Two hypothesis: the silica roots grew over the softer calcitic crinoid pieces rubbing grooves into them as the currents caused the roots to sway. Second: the roots had living tissue on the outside that secreted acid that caused the grooves. Knowledge of extant sponge anatomy might help answer this question. Photo 1: average root diameter about 0.6 mm. Photos 2 and 3: detail of first photo. Photo 3: roots growing around section of crinoid columnals with grooves in columnals. Dilliard, Kelly & Rigby, J. Keith. 2001. The new demosponges, Chaunactis olsoni and Haplistion nacoense, and associated sponges from the Pennsylvanian Naco Formation, Central Arizona. Brigham Young University Geology Studies. 46. 1-11. http://geology.byu.edu/Home/sites/default/files/geo_stud_vol_46_dilliard_rigby.pdf @TqB

Alternate title: I found Pennsylvanian fossilized Sesame Wasa Crispbread; is it safe to eat? I have visited the Pennsylvanian Naco Formation east of Payson, Arizona several times this long hot summer and found some interesting sponges. My most interesting find was this 5 cm wide sponge that looked almost exactly like a Wasa Crispbread with sesame seeds on top. I was about to nickname it a Wasa sponge until I found out that it had a genus name: Stioderma. Pennsylvanian Desmoinian Stioderma occur in Texas. Link It is amazing how many fossils I have identified from the Pennsylvanian Naco Formation by reading references from fossils found in Texas and Oklahoma: thanks. link to Collections I found a new 5 cm sponge that sort of looks like a horn coral, but it has spicules. The area contained the usual suspects such as this 165 mm long Wewokella solida Link. and this 50 mm Chaunactis olsoni that the Arizona Museum of Natural History expresses interest in and hopefully will get it.

I have found some Pennsylvanian silicified “wood” from the lower part of the (~207 mya) Naco Formation in Arizona. This is the first recorded instance of likely plant material from the Naco. The formation is all marine in the section that I found it in and has lots of crinoids and brachiopods. One piece has some slight plant like internal texture with isolated circles and curved hash. Photo of side view of 90 mm wide piece with calcite rhomb molds. Most of the wood from that time had distinctive exteriors such as Calamities, Lepidodendron and Sigillaria. Any idea of what my pieces of wood might be? Could they be internal pieces of above mentioned varieties without the distinctive texture? Could it be a tree fern such as Psaronius? @paleoflor Attached picture of single piece on a blue zippered notebook is about 185 mm long.

ARIZONA FOSSIL ADVENTURES By Chris Schur Exploring the Winkelman Red Brachiopod Site. On Highway 77, one mile north from the turnoff to Winkleman is one of the most awe inspiring scenes to be found in Arizona. Here, the road cuts through a vaulted limestone canyon hundreds of feet deep, with the multihued layers clearly visible. At this location lies an old quarry on the north side of the road which cuts right into the Paleozoic Naco limestone cliffs. This February, we visited this site with some paleo friends to examine the fauna present and determine the suitability for future outings. We found that large boulders of limestone littered the bottom of the old abandoned quarry, which were once part of the surrounding cliffs. A hundred feet or so into the man made canyon, the limestone boulders contain bright red chertized fossil casts of several types of brachiopods, crinoids and bryozoans. Also present everywhere are worm burrow trace fossils, found in a spectacular violet hued limestone matrix. Description of fauna present: Brachiopods. Two types of marine brachiopods are abundantly preserved in red chert. The first type, a small Spirifer ranges in size from less than a quarter of an inch upwards to over an inch. This is by far the most desirable, but less common of the two brachs seen here and are usually preserved as complete three dimensional casts with limestone filled centers. The second and far more common is an unidentified rounder heart shaped brachiopod. With sizes ranging from one half to two inches in diameter, including many large and fragmented shell pieces. The wall is thin, and the center also filled with limestone, so one must be careful in using acid to extract the delicate red or pink chert specimens, or they will fall apart. Crinoids. This site contains some of the largest crinoid stems I've ever seen. While most are 3/8 of an inch in diameter, we found many much larger. The really big ones were nearly an inch in diameter, with a small rounded five point star shaped central canal. Countless smaller stems are seen as well, forming much of the grey colored limestone matrix itself, often referred to as "crinoidal limestone". Some of the largest ones however were preserved in red chert, and several one to three inch long specimens were retrived. Bryozoans. Two types of "moss animals" were found here. The common net like Fenestrellina types were abundant, filling in the spaces in the limestone matrix with mostly small fragments. The second, and much more common type was a small branched animal, usually preserved as a black film on many of the loose limestone boulders in the bottom of the canyon. Trace Fossils. On the visible surfaces of many of the large boulders in the bottom of the canyon are the trace remains of hundreds of channels and tunnels in the fossilized ocean bottom from burrowing invertebrates typical of mid to late Paleozoic time periods. On many of the exposed surfaces of the limestone, we can see one to two inch diameter trails where the animal tunneled through the muddy bottom crossing and passing through the tunnels of others as well. Often we see and entire block of violet hued limestone with burrows passing through the stone, filled in with white limey sediment, layer upon layer as the sea bottom slowly filled in with more mud. Cross sections of the burrows are oval in shape, and typically an inch tall, and 1 1/2 inches wide. As for a possible animal that formed the burrows, the fossil record here does not preserve any mollusk or crustacean large enough to have made them, indicating that either it was a soft bodied animal that did not fossilize or a crustacean whose chitinous outer exoskeleton that dissolved or fell apart soon after death and prevented fossilization as well. A useful observation is that within the violet limestone matrix containing the burrows, we find many of the red chertized brachiopods intermixed. This indicates that the red brachs coexisted with the burrowing animals and shared a common ecosystem. Extraction of the Fossils. When you visit this site, be prepared to do a bit of hard rock quarrying to remove the good specimens. Because this site has been known for years, don't expect to pick up small pieces of limestone matrix and have them filled with choice specimens! The best specimens will have to be removed with hammer and chisel from the large limestone blocks. We have found that a standard geological pick is not enough to extract the material. The best tool is a heavy duty 1/2 to 1 inch diameter masonry cold chisel and a heavy hand sledge. Also mandatory will be a good pair of safety glasses to deflect flying shards of matrix, and a pair of work gloves to protect your hands. Remove the prospective fossil by chiseling a deep channel around it, keeping at least an inch away from the delicate red chert. When the channel is at least an inch deep, you can pop it off with one swift blow, or work around the base with a smaller chisel. Once the specimen and surrounding matrix is removed, the fossil can either be displayed as is, or removed from the matrix. While mechanical preparation works well here, some success with smaller specimens can be had by dissolving the limestone with acid. For most small pieces, vinegar works well, remove only the outside material but do not leave in too long because many of the larger brachiopods are filled in the center with limestone which helps support the fragile shell material. Muriatic acid that has been diluted with water works faster, but should only be used under adult supervision. The large crinoid stems come out particularly well with the acid treatment, leaving a hollow center in the stems. Further explorations. We have not been further up the canyon, however there is no doubt that the best and freshest specimens will lie in the rugged cliffs beyond the collection site. While such a hike should not be attempted by the inexperienced, prepared fossil hunters may uncover a rich bounty of more red chertized fossils in the walls beyond. The Pennsylvanian Naco limestone contains in other parts of the state some of the best brachiopod fossils to be had, along with plentiful bryozoans and other interesting marine invertebrates. Other layers of limestone contain no apparent fossils at all. But it is the lure of the ancient sediments that push the fossil hunter onward, always hopeful that next discovery could be just around the corner! For furthur reading on this spectacular area, refer to USGS Bullitin 176 highway road log by Wess Pierce. I wish to thank Tom McGarvin of the Geological Survey office in Tucson for helping with the identification of the sites age.

I found this strange Composita subtilita at the Paleo Site bear Kohls Ranch, Arizona. It is from the Middle Pennsylvanian Naco Formation. Does anyone know what’s going on with the strange pattern? Flip side I also should be able to provide slightly higher quality photos if needed, I just reduced the quality to be able to post several PS-I wasn’t sure if I should post this here since I have an ID, so please move it if it shouldn’t be

Any idea what these silicified possible crinoids are? Are they even crinoids? They are from the Pennsylvanian Naco Formation from near Payson. The ones in the photos (both sides are shown) are from 0.8 to 1.5 cm wide. @crinus These two references might be of help. Anyone have access to the photos from these? Webster, G., & Olson, T. (1998). Nacocrinus elliotti, a New Pachylocrinid from the Naco Formation (Pennsylvanian, Desmoinesian) of Central Arizona. Journal of Paleontology, 72(3), 510-512. Webster, Gary; Elliott, David. (2004). New information on crinoids (Echinodermata) from the Pennsylvanian Naco Formation of central Arizona. The Mountain Geologist. 41. 77-86.

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.

I found part of a sponge from the Pennsylvanian Naco Formation. The sponge is 5 cm in maximum width. The needle like structures average about 0.2 mm in diameter. Are the needle like structures part of a sponge body or part of the roots? Species? A cross section shows the needles radiate from the center. Photos: 1 top 2 bottom 3 cross section 4 detail