Ammonoidea

The Museum in Green River, Utah

2011-12-28T12:03:00.000-07:00

The Mancos Shale exhibit at the John Wesley Powell River History Museum in Green River Utah, is now open. Along with a couple of dinosaurs and other murals, it is a very nice addition to the museum. In the distance on the right you can see the ammonite I found and posted about back in this post, and after it was prepared in this post. Here is a view of the specimen with the mural

For a cold, snowy, December day

2011-12-13T09:04:00.000-07:00

San Rafael River cutting through the Swell Just to remember those hot days of summer and early fall in the desert. The Sinbad Formation of the Thaynes Group slopes down to river level on the left, bleached rocks of the Moenkopi Group up to the maroon Chinle Formation on the slopes of Assembly Hall Peak, with a cap of Wingate Sandstone, and Kayenta and Navajo above that on the cliffs

Of Cephalopods and Sponges

2011-10-06T22:51:00.000-06:00

Early Ordovician orthoconic nautiloids in a sponge/algal deposit, back when life was just beginning to diversify. Early Triassic ammonoids in a sponge/microbial deposit, back when life was beginning to re-diversify. Just after the Permian-Triassic mass extinction.

Silica Replacement

2011-07-13T09:13:00.001-06:00

An update for this old Calcite Replacement post. After finding another small ammonoid (above) in the same beds, and a discussion on TONMO, I've realized the pattern on the two fossils is that of "Beekite". Not having a lot of experience with silicified cephalopod fossils around here, I got out the acid bottle, fizz on the matrix, no fizz on the fossil. So instead of a Calcite replacement,

The First Utah Cephalopod Fossil

2011-05-04T09:52:00.000-06:00

Title Page Although fossil cephalopods had probably been collected by the Native Americans, fur trappers and early Immigrants for years, the 1859 Simpson Survey was one of the first scientific expeditions that collected fossils, and probably the first to collect cephalopods and have the results published. Mr. Henry Englemann "the zealous geologist of the party", collected what is to my

Unexpected ammonoid

2011-04-28T20:38:00.000-06:00

Churkites cf. C. noblei An internal mold of the body chamber, much like the first photo in THIS old post. This fossil means some of the beds I was collecting in are older than I thought or this ammonoid ranged into younger rocks. Only more collecting will determine how it fits in the column.

Payday for an Amateur Paleontologist

2011-04-06T09:11:00.000-06:00

From the Merriam-Webster Dictionary "Amateur: one who engages in a pursuit, study, science, or sport as a pastime rather than as a profession". It don't say anything about getting paid, just about having fun or making a job out of it. I guess that one of the greatest means of compensation someone that does this for fun can receive, and retain an amateur standing, is to have a fossil named after

Intraspecific variation in Forresteria

2011-03-23T08:52:00.010-06:00

Forresteria alluaudi (Boule, Lemoine & Thevenin) 1907, from depressed, evolute, spinose to compressed, involute, almost smooth, a nice range of intraspecific variation. Is it any wonder why these, and some like these, were placed in 4 separate species in 3 separate subgenera (Reeside, 1932), Barroisiceras (Forresteria) forresteri, B. (F.) stantoni, B. (Alstadenites) sevierense, and B. (Harleites

Scaphites hippocrepis and S. leei

2011-01-03T14:38:00.009-07:00

Scaphites hippocrepis and S. leei, Early Campanian (Late Cretaceous) Scaphitids. A row of ventrolateral tubercles, an inner row of tubercles on the body chamber and a constricted collar at the aperture. Best seen on the micromorph of S. leei in #22 below, and on the macromorph in #27, are dorsal lappets.Below is a drawing of the dimorphs of S. hippocrepis. The collar shows well but the dorsal

Juvenile heteromorph

2010-10-31T11:08:00.002-06:00

Another small heteromorph from the Cretaceous Mancos Shale. This one has the body chamber preserved so it is freshly hatched or up to a few weeks old. 1mm diameter at widest point.

SR2 Anasibirites Bed

2010-09-21T07:52:00.005-06:00

Like at all other localities, about as thick as the hammer. The lower beds at this locality are a lot less fossiliferous than at any other, they have also been baked by the nearby igneous intrusions, so I don't think they are worth collecting in detail.A closeup. All the small circular spots are drippings from the Pinyon tree above

Tirolites ?

2010-08-23T11:05:00.007-06:00

? Tirolites body chamber castFrom above the "Clam Wall" and below the "Spathian Gap", geographic outcrop nicknames that don't mean anything to anyone unless you have a copy of my field notes from 15 years ago, sorry. Even below M109 of anothers' notes. Not a very good fossil, but it may be important.

Calcite Heteromorph

2010-08-17T20:58:00.004-06:00

A small portion of a heteromorph ammonoid, possibly Allocrioceras. This thing is only about 1.5mm long, photo taken through the eyepiece of my microscope. Dorsal side toward viewer, without impressed zone so it was completely evolute and probably open whorled, not enough preserved to tell if it was helical or not. From the Upper Cretaceous Mancos Shale, lower Upper Turonian Scaphites

Rudolftruempyiceras Guex & Bylund 2010

2010-06-16T12:09:00.006-06:00

The name Boreoceras Dagys & Ermakova (1988), has been replaced with Rudolftruempyiceras Guex & Bylund 2010, Family Columbitidae, see Guex, J., Hungerbuhler, A., Jenks, J., O’Dogherty, L., Atudorei, V., Taylor, D., Bucher, H., Bartolini, A., 2010, Spathian (Lower Triassic) Ammonoids from Western USA (Idaho, California, Utah and Nevada), Memoire de Geologie (Lausanne), No. 49, on page 29. The name

Cephalopods - Present and Past

2010-06-03T20:53:00.001-06:00

Cephalopods - Present and Past:Stephen, D.A., Bylund, K.G., Bybee, P.J. and Ream, W.J.: Ammonoid beds in the Lower Triassic Thaynes Formation of western Utah, USA, p. 243-252In the 20 years since I located the Triassic fossil bearing beds in the Confusion Range of western Utah, I have only co-authored papers on sponges and gastropods. Now, a paper on the Ammonoids. The first of many I hope.

Calcite Replacement

2010-04-18T16:10:00.004-06:00

Calcite replaced ammonoid shell(is that really angular coiling in the umbilicus?)another showing partial suture line

Early Triassic Lilliputians

2010-03-30T20:21:00.005-06:00

LilliputiansJust for comparison, the typical size of previously studied Early Triassic gastropods with a Dime for scale.

Early Triassic Gullivers

2010-02-10T20:12:00.004-07:00

Gullivers from a Lilliputian worldArticle abstractI have been walking on them for almost 20 years, so I knew they were there, I new they were big, and I knew their age, I didn't realize the whole story. I had tunnel vision, only seeing the ammonoids and occasionally looking at the Lilliputians in the overlying beds. The last few years have been different, looking at the other fossils a little

Placenticeras syrtale

2010-01-17T17:05:00.002-07:00

Placenticeras syrtale prepared and ready for displayIt may end up in the John Wesley Powell River History Museum in Green River, Utah

Conglomerate again

2010-01-09T21:42:00.006-07:00

On the south end of the outcrop is this conglomerate with some very large cobbles. There are few places where this bed rests on a limestone bed full of chert nodules, and a place where the calcarenite beds rest directly on top of this bed. The matrix looks like the calcarenite but a little more analysis is needed to verify.The hammer is sitting on top of the Conglomerate, the beds above are the

Permian/Triassic Transition

2009-11-28T11:07:00.005-07:00

CP1CP1 conglomerateDH1DH1 brecciaJust a few pics to ponder as the details are yet to be worked out.

Who's Collecting Crittenden Springs?

2009-11-16T17:22:00.008-07:00

Jim Jenks is writing a paper on the Early Triassic ammonoids he has collected over the years at the Crittenden Springs locality north of Montello, Nevada. He went out a few weeks ago to take some photos of the beds he collected and found that someone has been out there recently. Large excavations and partially collected fossils is what he found. One of the large holes foundA large Churkites

Early Middle Ordovician Cephalopods

2009-11-10T07:12:00.009-07:00

I went with Dan and his Paleo Class out into Utah's West Desert. We collected some trilobites from the Cambrian Wheeler Shale, some brachiopods from the Permian Gerster Limestone, and then some fossils from the Ordovician Juab Limestone and Kanosh Shale.The first photo is a Tarphycerid from the Juab Limestone, the second, a large Endocerid in a block of limestone from the Kanosh Shale.Just a

MC Anasibirites Beds

2009-10-10T21:58:00.005-06:00

Permian on the left, Black Dragon (Moenkopi red beds on left), Thaynes and then more redbeds on right(possibly Chinle conglomerate capping hills on right)?Hemiprionites, Anasibirites and WasatchitesAnasibirites beds (gray) in center, about 20-25cm thick, with small "body chamber beds" (15cm thick) below,with high angle fault. Beds with Inyoites and Guodunites below, Thick 50-60cm brown bed.Cool

Early Triassic Anasibirites Beds

2009-10-04T11:07:00.004-06:00

The Anasibirites Beds in the Confusion Range (above) comprise approximately 30 cm of limestone packed with cephalopod shells. On a recent two week trip collecting fossils from a few new outcrops and a couple of classic ones, I noticed how similar they all are.From the Cephalopod Gulch locality, near Salt Lake City, where Mathews first described the Anasibirites fauna in the Western US (above).

Uintacrinus and Desmoscaphites bassleri

2009-09-15T14:21:00.005-06:00

Uintacrinus from the Mancos Shalea small fragment of Desmoscaphites bassleriThese fossils were found by Rod Scheetz (BYU Museum of Paleontology) in the Mancos Shale southeast of Green River. The small fragment he found closely matchs the one I found (see Aug. 12, 2009 post). I am now quite sure they are D. bassleri, and the small Scaphites is S. leei, from the Latest Santonian. D. bassleri has

Spathian? Ammonoids

2009-09-09T21:58:00.004-06:00

Small ammonoids and orthoconic nautiloids found in a gray limestone concretion. Probably from the Spathian part of the FormationJack RabbitEarthquake damage in Wells, Nevada, waiting to be repaired?The Ranch, in the distance, and what outcrops there are in the foreground.Outcrops of Smithian rocks were not found on this trip :(

vermiformis? Beds

2009-08-12T20:36:00.003-06:00

a small Scaphites from low in the ?Lower Emery SS beds of the Mancos Shale east of Green River.Body chamber from Clioscaphites ?vermiformis. These seem to have a lot more ribs than typical C. vermiformis.

Sinbad Member Southern San Rafael Swell

2009-08-02T08:44:00.003-06:00

Hondoo Arch. Limestone of the Jurassic Carmel Formation holding it up above the Navajo Sandstone, Kayenta and Wingate cliffs below, Varicolored Chinle below, and the upper part of the Moenkopi at the base.Yellowish Sinbad Limestone on the other side of a fault, the gray fossiliferous base seen below the upper dolomitic beds.It is hard to separate in this view, the Sinbad is in the middle,

Sinbad Member near it's Type locality

2009-07-25T21:12:00.005-06:00

Sinbad Formation of the Thaynes Group capping mesa, Black Dragon Formation of the Moenkopi Group just below (oil bleached in this area of the San Rafael Swell) and the ?Coconino/BlackBox Dolomite in foreground. One of the many waterpockets visible in the wash.A tadpole in one of the waterpockets, probably a Spadefoot toadThe northern exposure of the Sinbad. Butte in background made up of

8ISCPP

2009-07-07T11:48:00.005-06:00

8th International SymposiumCephalopods - Present and Past2010 @ Dijon, FranceAugust 30th to September 3rdI better start getting my poster ready

Critters that distract you from fossil hunting

2009-07-05T19:39:00.003-06:00

Dan and Catherine playing with a Striped Whipsnake at DHMormon Crickets were quite common at DVNot shown are all the lizards and tarantulas that were not photographed because I was to busy watching them.

Tentacles/Arms/Suckers

2009-06-22T21:07:00.003-06:00

It's alive! I wonder what an ammonoids arm looked like?The Enteroctopus dolfleini at the Steinhart Aquarium in the California Academy of ScienceSan Francisco, Ca.

Scaphitoid

2009-06-06T19:54:00.009-06:00

Scaphitoid Cephalopod, Yezoites, possibly a new species.A canyon cut through the Ferron SandstoneMancos Shale

End of April Field Trips

2009-05-01T07:53:00.006-06:00

Lara and Holly at DV1A nice view of DV2Don't take my waterSunrise at the Border Inn, Baker, Nevada.The top of Notch Peak just visible below the "SLOTS" sign.I lost all of $5 at them one armed banditsJim, Jean Guex, Viorel Atudorei, at Cowboy Pass (CP1)

April Field Trip

2009-04-19T19:23:00.003-06:00

Camp in the Wheeler Amphitheater.No ammonoids on this trip so this is the only pic I took.

Change

2009-04-12T13:34:00.008-06:00

On March 30 Obama signed the Omnibus Public Land Management Act of 2009. Part of that is the Paleontological Resources Preservation Act, Specifically Title VI, Subtitle D (select text of legislation, then S.22.ES) . A provision to allow casual collecting is incorporated, but is very vague, otherwise a permit is required to collect any fossils on public land. Looks like change has come.

Polymorphism, Intraspecific Variation, Dimorphism, Covariation

2009-03-29T11:17:00.003-06:00

A few terms that at first seem to be self explanatory. The first two seem to be interchangeable as do the last two. Reading a paper the other day, the title used one term but the body of the paper was filled with the other term. Could someone fill me in on the correct usage of these four terms, are they really all about the same. For years an ammonite was an ammonite until I found out that

More from 3-21-09 Field Trip

2009-03-25T09:14:00.004-06:00

Alex, in the center,watching as I uncovered the big one.He likes ammonites as much as I do.this is the sign Alex had pinned to his pack. A future Paleontologist for sure?Looking for Prionocyclus at Stop 2Looking for Scaphites at Stop 1

3-21-09 Field Trip

2009-03-22T15:49:00.003-06:00

Jim Kirkland, State Paleontologist, holding the large Placenticeras syrtaleFolks admiring another large ammoniteWraping up some of the peices of the big one

GSA Rocky Mountain Section

2009-03-19T20:50:00.004-06:00

AMMONOIDS OF THE LOWER TRIASSIC THAYNES GROUP IN THE PAHVANT RANGE, UTAHEARLY TRIASSIC CONODONTS IN THE PAHVANT RANGE OF CENTRAL UTAH

Albuquerque Museum Ordovician Nautiloids

2009-03-12T07:15:00.004-06:00

Types of a few OrthoconesPlectolites major unpublished paratype from near IbexThe collection cabinetsMe and JohnThe type of Cacheoceras uninodum

Like a Rainbow

2009-02-28T20:47:00.005-07:00

Shes like a rainbowComing, colors in the airOh, everywhereShe comes in colors

DH4 beds

2009-02-22T21:27:00.003-07:00

Section DH4, beds not numbered.

DH4 Gastropods

2009-02-21T22:36:00.007-07:00

Gastropods from below Meekoceras quarryGastropods from south below Meekoceras quarryGastropods from the knoll North of quarryOwenites? from South below Meekoceras quarryI found a few faults around my old Meekoceras quarry, one divides the outcrops below the quarry into an area below the quarry and an area south below the quarry.

Gastropod Shale 2 at DH1

2009-02-12T21:43:00.003-07:00

GastropodsAmmonoids and Gastropods

Groups, Formations, Beds, Horizons and Zones

2009-01-27T08:23:00.010-07:00

A little snippet (edited) from an email to Dan:Lucas et al 2007 (on the Timpoweap) raised the Thaynes and Moenkopi Formations to Group status. If we dont accept Lucas et al, do we extend the Sinbad Member into the Confusion Range or extend the Thaynes Formation into the Pahvant Range. To me the rocks in the Pahvant Range, a few thin limestone beds in a fairly thick shale sequence, are more like

Inyoites from my "Meekoceras" Quarry

2009-01-23T21:19:00.007-07:00

One of the Inyoites found near my old "Meekoceras" quarry. Some of the saddles seem to have the same ammonitic character as the ?Flemingites below. This is starting to look like an artifact of preservation more and more. It would be nice to see how high on the saddles the serrations of the lobe go up on the inner parts of the septa, I would have to break the suture back to see this. The

DH-4 Observations

2009-01-18T21:14:00.006-07:00

I decided to drive out to the Disappointment Hills on Saturday morning. Very little snow on the south facing slopes in the House and Confusion Ranges, down quite low on the north slopes, the roads are in good shape and were actually dusty. No snow at the eastern outcrops except for a couple of drifts on some of the north slopes, I didnt get up to DH-1. The sun was shining and the temp. was

Albuquerque Museum

2009-01-10T09:03:00.003-07:00

After a week in Cuba, New Mexico, I stopped off at the museum in Albuquerque. These are pictures of the ammonoids Jim collected and donated. A very nice display.

Flemingitid?

2008-12-15T20:51:00.004-07:00

View showing longitudinal sculpture Apertural view

2008-12-12T08:20:00.001-07:00

Close-up of the exposed sutures

Flemingitid? Suture

2008-12-11T09:48:00.006-07:00

Suture of the Flemingitid? the top is the last oneshowing the suture near the umbilicus.The specimen has a lot of phosphate replacement like most of the other fossils from this quarry. I dont know if this has deformed the suture line, some look distorted but for the most part, the suture line shown seems to be fairly well preserved.

Flemingitid ?

2008-12-10T21:13:00.003-07:00

From my old "Meekoceras" quarry (in section DH-4), w/Aspenites, Inyoites, Proptychitid. Bed & stratigraphic position unknown but possibly equivalent to bed 9???

Manuscript resubmitted

2008-11-26T08:05:00.010-07:00

AMMONOID BEDS IN THE LOWER TRIASSIC THAYNES FORMATION OF WESTERN UTAH, USADaniel A. Stephen, Kevin G. Bylund, Paul J. Bybee, and Wesley J. ReamDan sent in the revised manuscript and figures last night. Reviewers should be getting a copy shortly. I think it looks and reads great. Between me and the reviewers, Dan had a handful, trying to keep everyone happy and still writing what he wanted, I

Lanceolitidae

2008-11-06T13:54:00.004-07:00

Lanceolites ?bicarinatus on the left and the one I found in April (this post) on the right. They seem to have all the same elements but the L. ?bicarinatus seem to be a little more ammonitic. Perhaps the ammonitic elements were worn off of the right specimen?

DH1 Annotated Outcrop Photo

2008-11-05T09:33:00.002-07:00

Just because the beds show up so well through the snow.

Dan's Paleontology Class

2008-11-01T20:43:00.003-06:00

Dan and his paleo students in the Wheeler Amphitheater looking for Trilobites

At Jims house

2008-10-27T20:50:00.004-06:00

Jim Jenks, Dr. Hugo Bucher, Dr. Arnaud Brayard and Kevin Bylunda very small part of Jim's fantastic collection seen over my shoulders.

In the Field

2008-10-19T20:53:00.005-06:00

Dr. Hugo Bucher, Dr. Arnaud Brayard and Jim Jenksout on the outcropArnaud at DH-1 in the snowDawn getting ready to take vengence on a fossil

DH-1 Bed 10

2008-09-07T18:36:00.004-06:00

Something found this weekend. Sutures show well on the lower part of the whorl (bottom of photo), above the crack (on the left) are the inner sutures (in the impressed zone).Another view of the same specimen.

Xenoceltites

2008-08-11T17:59:00.004-06:00

An update for this old postXenoceltites-Boreoceras-WyomingitesI found an old photo of the specimen on display at the museum. Where did those constrictions come from? I am leaning more toward Xenoceltites now, as the sculpture, especially on the early whorls, is more like it than of Wyomingites. I could have swore all the whorls were smooth.

Measuring Early Triassic Sections

2008-07-15T06:34:00.004-06:00

Section DV-2 is just on the other side of this outcrop. Shown are beds 1-4 with many smaller or unfossiliferous beds in with them. Only the beds containing ammonoids are numbered.Jim, Dawn and Dan standing on Bed 4 at DV-1

Baby Ammonoids, Baby Gastropods

2008-06-23T07:14:00.010-06:00

Small ammonoids among small gastropodsA newly hatched Baculites ?More small ammonoids and gastropods with a fish scale.From the Cretaceous Mancos Shale, Scaphites whitfieldi Zone, the coiled ammonoids could be Scaphites whitfieldi or Prionocyclus novamexicanus.

DH-1 Bed 7.6

2008-05-18T12:07:00.002-06:00

From lavender beds below bed 8

DH-2 Photos

2008-04-28T08:28:00.008-06:00

A large Arctocerid mold, the body chamber was filled with mud so it is preserved, the phragmocone was probably crushed after it left it's imprint in the soft bottom.Jim collecting DH-2 bed 1The DH-2 anticline looking south.Permian red beds in the foreground, the basal Thaynes limestone on the south side of the north DH-2 fault well exposed beyond.

Something new (at least to me)

2008-04-20T18:57:00.005-06:00

I found this while doing a little mapping this weekend. I think it is some form of Ussuriid. From the Early TriassicSee this post for update

Presentation on line

2008-04-04T18:12:00.002-06:00

If you go to the abstract, you can now download a pdf file of the presentation I gave at the GSA meeting in Las Vegas last month.Abstract for Presentation 12-94.8 Mb presentation handout download.

GSA Las Vegas

2008-02-12T10:22:00.000-07:00

Well, Wes found out he cant give the talk at the GSA meeting in Las Vegas. The honor falls to Me!Paper No. 12-9 11:00AM-11:20AM, March 20, 2008A first time for everything I guess.

Clypeoceras may be Guodunites

2008-01-29T07:38:00.002-07:00

A hint in the air of an upcoming publication in which the "Koninckites" > Clypeoceras of the Confusion Range will be assigned to the Genus Guodunites.see this post http://ammonoidea.blogspot.com/2007/07/un-identified-ammonoids.html

Churkites vs Arctoceras

2008-01-09T11:17:00.001-07:00

Churkites noblei Jenks 2007The ornamentation is exactly like Arctoceras tuberculatum, the only difference is the shape of the venter. These have an acute venter, becoming almost oxyconic in large shells and Arctoceras has a well rounded venter (almost semi-circular). This could be sexual dimorphism with the round ventered forms being female and the acute ventered forms male.Of course there are

Opportunistic Bloom?

2008-01-02T12:56:00.000-07:00

I am really starting to wonder if the Anasibirites Beds could preserve an opportunistic bloom. If the Prionitids (and not all the other ammonoids) began or found a way to prey on the micro gastropods of the time they may have had a great advantage and a large amount of food. Whether the beds in the Confusion Range preserve a mass mortality event or just the preservation of an unusually high

Syngastrioceras websteri

2007-10-10T19:46:00.001-06:00

Three views of what I think now is Syngastrioceras websteri Titus 2000. The top two are latex casts of the external mold (bottom).

Eumorphoceras girtyi zone

2007-10-04T21:00:00.001-06:00

I found a mold of either Eosyngastrioceras inexpectans or Syngastrioceras websteri in the E. girtyi zone yesterday. These two are nearly identical going by shell shape and ornamentation, the suture would really tell the story, but there are no sutures in fossils that only have external molds.

Cardioceras hyatti

2007-09-22T20:37:00.001-06:00

Found these Cardioceras hyatti in the Redwater Member of the Stump Formation. I had been looking for new collecting localities on Google Earth all summer, and decided to stop by on the way home from Big Wonderful this weekend, glad I did!

Ammonoid collecting

2007-09-22T20:27:00.001-06:00

Dieter Korn on the left and Alan Titus on the right. at Granite Mt., Juab County Utah September 1, 2007 I went collecting with Dr's Alan Titus and Dieter Korn on August 30 thru Sept. 3, 2007. It just happened to be the hottest September day on record, 104 on the 2nd. Still, I had a great time and learned alot from these guys.

Un-identified Ammonoids

2007-07-30T12:47:00.001-06:00

A very hot day in the West Desert of Utah netted these. The first (bottom) I have identified as ?Koninckites on the web site, dont know if that ID is anywhere close. Compressed shells with a well rounded venter, the umbillicus is shallow, the umbillical walls almost non-existant, especially on older shells. The only ornamentation is well formed growth lines, not strong enough to be called ribs,

Belemnites

2007-06-12T12:31:00.001-06:00

A spur of the moment trip to the Vernal area last saturday netted these Belemnite guards. All? Pachyteuthis densus from the top of the Curtis Member of the Jurassic Stump Formation. Who is the author/s of P. densus? I have "(Meek and Hayden) 1858" [I cant remember where I got that] on my website, all other references on the web just have "(Meek)" with no date.

Some New Papers

2007-06-05T19:20:00.000-06:00

Lucas, S. G., Goodspeed, T. H., and Estep, J. W., 2007, Ammonoid Biostratigraphy of the Lower Triassic Sinbad Formation, East-Central Utah, in, Lucas S. G. and Spielmann, J. A. eds. Triassic of the American West, New Mexico Museum of Natural History and Science Bulletin 40 Lucas, S. G., Krainer, K., and Milner, A. R. C., 2007, The Type Section and Age of the Timpoweap Member and Stratigraphic

UFOP Convention, Green River, Utah, May 17-20

2007-05-31T10:13:00.000-06:00

A few pics from the field trip Saturday around the Crystal Geyser Quarry. Looking thru the Cedar Mt. Formation for bones. Bob Bakker gave a very nice presentation the night before, all about bullets and dead bodies.

LUMPER

2007-05-08T12:27:00.000-06:00

I feel like LumpingLumper/Splitter DefinitionFungus Lumper

More Polymorphism ?

2007-04-09T06:56:00.002-06:00

In the Jurassic Stump Formation (Oxfordian) the Cardiocerids also show alot of polymorphism. Many genera and species have been described for what is possibly just a single species.

Triassic Paleoenvironment, Paleogeography and Shell Beds

2007-03-26T10:29:00.000-06:00

A list of some references for the anasibirites bedsRoger L. Batten and Wm. Lee Stokes, 1986, Early Triassic gastropods from the Sinbad member of the Moenkopi Formation,San Rafael Swell, Utah. American Museum Novitates no.2864, .33 p.Ron Blakeys web site.DIANA L. BOYER, DAVID J. BOTTJER and MARY L. DROSER, 2004, Ecological Signature of Lower Triassic Shell Beds of the Western United States,

Anasibirites-Wasatchites a polymorphic species?

2007-03-26T09:20:00.005-06:00

Placenticeras syrtale dimorphs (top) and Anasibirites and Wasatchites (bottom)With the amount of intermediate forms between Anasibirites kingianus (Waagen) 1895, and Wasatchites perrini Mathews 1929, is it reasonable to consider them as a dimorphic/polymorphic species?From the website: "Because of the variable morphology in some populations all specimens are a seperate species, or all are one

Xenoceltites-Boreoceras-Wyomingites

2007-03-20T12:22:00.002-06:00

In the Anasibirites beds of the Confusion Range is a serpenticone ammonoid I refer to Wyomingites. I cannot see any constrictions on the early whorls (maybe just an artifact of preservation) so I am hesitant to refer it to Xenoceltites. Boreoceras, as figured by Dagys 1999, and the fossils in the Confusion Range look to be congeneric if not conspecific. However, the name Boreoceras is

Scaphites renamed

2007-03-19T19:11:00.001-06:00

I just got a copy of this paper:Cooper, M. R., 1994, Towards a phylogenetic classification of the Cretaceous ammonites III, Scaphitaceae: Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen, 193 (2), 165-193.referenced from Cobban, W.A., Walaszczyk, Ireneusz, Obradovich, J.D., and McKinney, K.C., 2006, A USGS zonal table for the Upper Cretaceous middle Cenomanian−Maastrichtian of the

The Beginning

2007-03-19T12:20:00.000-06:00

The start of the ammonoidea blog. More to come.