tag:blogger.com,1999:blog-9760178858853233432024-03-14T00:18:44.309-06:00AmmonoideaA Fossil Cephalopod BlogKevinhttp://www.blogger.com/profile/08281939757317188024noreply@blogger.comBlogger126125tag:blogger.com,1999:blog-976017885885323343.post-23940176324009587532023-07-17T14:56:00.001-06:002023-07-17T15:01:26.166-06:00Devonian OrthoconesDevonian Actinoceratids in the Fitchville Formation on Wanlass Hill. Found by David Johnson earlier this year and reported to me :) I went out with him and a few other students to check them out earlier this year. Also, some nice coral (Syringopora) Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-9888226417341377572023-05-08T09:49:00.001-06:002023-05-08T09:49:48.711-06:00Early Triassic Stomatopod
Smith CPA, Aubier P, Charbonnier S, Laville T, Olivier N, Escarguel G, Jenks JF,
Bylund KG, Fara E, Brayard A., 2023, Closing a major gap in mantis shrimp
evolution - first fossils of Stomatopoda from the Triassic,
Bulletin of Geosciences, volume 98, issue 1; pages: 95 - 110 Abstract:Mantis shrimps (Stomatopoda) are marine benthic predators well known for their raptorial claws Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-61166268161135012822022-09-10T13:50:00.000-06:002022-09-10T13:50:14.212-06:00More TaxonomyA new paper just out trying to update the nomenclature and authorship of ammonoids:The higher taxonomic nomenclature of Devonian to Cretaceous ammonoids and Jurassic to Cretaceous ammonites including their authorship and publicationHoffmann, René; Howarth, Michael K.; Fuchs, Dirk; Klug, Christian; Korn, DieterIt may be the latest but it won't be the last. I'm sure that just like those back Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-58637310627001888682022-07-21T12:38:00.002-06:002022-07-21T12:39:59.929-06:00Paris Biota DecapodsThe Paris Biota decapod (Arthropoda) fauna and the diversity of Triassic decapodsAbstractWe describe here the early Spathian (Early Triassic) Paris Biota decapod fauna from the western USA basin. This fauna contains two taxa of Aegeridae (Dendobranchiata), namely Anisaeger longirostrus n. sp. and Aeger sp. that are the oldest known representatives of their family, thus extending its temporal Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-72402382362319382332022-04-15T08:51:00.005-06:002022-04-15T08:51:53.245-06:00Cephalopod PhylogeneticsThe more things are found to be the same the more they are found to be different.
It may never end
Pohle et al. BMC Biology (2022) 20:88
https://doi.org/10.1186/s12915-022-01284-5Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-58898662273532301202022-03-09T13:12:00.000-07:002022-03-09T13:12:40.672-07:00Ammonite Chamber Internal MoldAn internal mold of an ammonite chamber. Left, lateral view, right, apertural viewTwo views of an internal mold of one of the chambers from the phragmocone of an ammonite (Prionocyclus macombi Meek 1876). The chamber was hollow and probably filled with gas and a little liquid while the animal was alive, and was probably empty of any solids after it died. How long it sat empty on the Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-32493426447918375932021-12-05T13:57:00.001-07:002021-12-05T14:03:20.071-07:00The Canadian System (Period) as proposed by Flower (1957)Because the Cephalopods were so different, Rousseau H. Flower wrote proposing the Canadian System with four divisions of unspecified rank (Flower 1957 p. 17). Quoting from Flower:"Faunally, the Canadian is relatively isolated from the Ordovician above and is characterized by stocks of its own. In the cephalopods..., the Canadian-Ordovician boundary involves changes never lower than of Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-91743737015982402382021-11-08T09:21:00.001-07:002021-11-08T14:11:19.179-07:00Wiping the smile off the face of the horizontal NautiloidThe cover of New Mexico Bureau of Mines & Mineral Resources Memoir 32 (1977), and the description from inside the front cover (below) (both used with permission from the New Mexico Bureau of Geology and Mineral Resources). Showing the contented and smiling face of an orthoconic cephalopod with cameral (or siphonal) deposits counterweighting the gas-filled phragmocone letting it Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-48929145047217955832021-10-08T10:12:00.002-06:002021-10-08T10:20:31.456-06:00More exceptional fossil assemblages Adding to localities where fossils like those in the Paris Biota are found.Smith, C.P.A., Laville, T., Fara, E., Escarguel, G., Olivier, N., Vennin, E., Goudemand, N., Bylund, K.G., Jenks, J.F., Stephen, D.A., Hautmann, M., Charbonnier, S., Krumenacker, L.J., & Brayard, A., 2021, Exceptional fossil assemblages confirm the existence of complex Early Triassic ecosystems during Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-18805014441271183392021-06-29T15:15:00.002-06:002021-10-08T14:59:47.146-06:00Latest Smithian Ammonoids in northern UtahCorroborating the existence of a UAZ6 (Unitary Association Zone, a means of biostratigraphic correlation). See the paper linked below. Characterized by the ammonoid Psudosageceras augustum (Brayard & Bucher, 2008) in association with Xenoceltites subevolutus Spath 1930. Found in rocks previously assigned to the Induan (lower Lower Triassic) Dinwoody Fm., now assigned to the Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-78942770304235088442021-05-23T13:52:00.001-06:002021-05-23T13:59:56.108-06:00Dinwoody Ammonoids & NautiloidsLATE GRIESBACHIAN (EARLY TRIASSIC) AMMONOIDS AND NAUTILOIDS FROM THE DINWOODY FORMATION AT CRITTENDEN SPRINGS, ELKO COUNTY, NEVADAbyJAMES F. JENKS, TAKUMI MAEKAWA, DAVID WARE, YASUNARI SHIGETA, ARNAUD BRAYARD and KEVIN G. BYLUNDAbstract—We document a relatively small but very important late Griesbachian ammonoid and nautiloid assemblage from the Dinwoody Formation at Crittenden Springs, Elko Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-9628724275224455312021-03-18T16:46:00.000-06:002021-03-18T16:46:32.881-06:00Paris Biota Ammonoids & Nautiloids A very late postAmmonoids and nautiloids from the earliest Spathian Paris Biota and other early Spathian localities in southeastern Idaho, USAArnaud Brayard, James F. Jenks, Kevin G.Bylund and the Paris Biota Team 2019Part of a Special Volume dedicated to the Paris Biota of SE Idaho.Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-90314306205183605672020-07-06T12:26:00.000-06:002020-07-06T12:26:56.311-06:00Some Prionitids LumpedWith a few very narrowly defined species, The Prionitidae is a family of very closely related ammonoids. However most collections, especially from the western US, always contained "Prionitid" or "Prionitid indet.", Prionitids with bullae or ribs, maybe nodes or tubercles, that just didn't fit with any of the other described genera or species. With new collections from the Smithian (Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-1155558057533487392019-04-16T16:55:00.002-06:002019-04-16T16:55:31.272-06:00Sexual Dimorphism in AmmonitesSexual dimorphism as represented by the ammonite Yezoites frontierense (Cobban 1952)
Macroconch (female) 38mm on the left, microconch (male) 18mm on the right
Previously referred to Scaphites frontierense, presumably, the female was much larger to carry eggs. Many extant cephalopods (the Blanket Octopus for example) show the same relative (?) dimorphism with the males much Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-71884548271839360812019-03-28T12:29:00.000-06:002019-03-29T10:58:16.044-06:00Lower Ferron Sandstone and Juana Lopez Members of the Mancos Shale around the north side of the San Rafael SwellIn an attempt to show that the Juana Lopez Member of the Mancos Shale really does expose itself on the west side of the San Rafael Swell, I introduce some photos to help.
Lower Ferron east of Huntington (visible upper right).
Lower Ferron east of Huntington, these beds contain Prionocyclus hyatti near Mounds. They also form a small cliff under the Ferron Sandstone south Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-45581255589210366142019-03-27T19:57:00.001-06:002019-03-28T09:41:06.692-06:00Another Payday
Meekoceras bylundi Jenks & Brayard 2018Holotype
A little late, but...
https://albertiana-sts.org/2018/01/08/publication-announcement-smithian-early-triassic-ammonoids-from-crittenden-springs-elko-county-nevada/
Thank you Jim and Arnaud!
Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-73588527181919805592018-02-14T17:04:00.000-07:002018-02-14T17:09:03.442-07:00Giant Cephalopod Midden or Mosasaur FecesBack in 2011, and again in 2013, Mark and Dianna McMenamin postulated a giant cephalopod created a midden with the bones of Icthyosaurs. The internet came alive with much fanfare, comments, news, etc. probably because of the size the cephalopod would have had to been to form such a midden.
Well, back in 1954 two well-known cephalopod paleontologists, John B. Reeside and Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-32824798912446412162017-12-31T10:28:00.000-07:002017-12-31T10:28:12.383-07:00Adult size in Scaphites
Three adult specimens of Scaphites showing the size range. The two on the left are probably progenetic dwarfs of contemporary full size species. Pteroscaphites pisinnus (far left) from the Scaphites whifieldi Zone, undetermined example (center) from the Prionocyclus hyatti Zone, and Scaphites carlilensis (right) from the Prinocyclus macombi Zone. Only adults grow a hook for a Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-51810176861598662472017-12-18T14:43:00.001-07:002017-12-18T14:43:36.769-07:00Ugly Map ColorsToo bad modern geology is taking a step backward with their geologic mapping colors. I have yet to see an official standard calling out the new colors. You used to get a choice at stratigraphy.org, but no more. Are they using a traditional system for the sake of tradition under the guise of priority. This is almost as bad as illustrating ammonoids upside down of their assumed Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com1tag:blogger.com,1999:blog-976017885885323343.post-76690412872397078002017-11-10T11:10:00.003-07:002021-02-11T12:13:01.232-07:00Ammonoid Family Reunions (revised Feb. 11, 2021)Two family reunions occurred in the distant past, the
Prionitids and the Cardioceratids, this is a short review of those events. The thing that draws attention to these two
reunions is that members of the two families gathered in abundance and almost to
the mutual exclusion of other families.
Both are recorded in rocks representing a relatively short time-span, a
single biozone, the Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com5tag:blogger.com,1999:blog-976017885885323343.post-84992380648964212202017-11-08T14:50:00.001-07:002017-11-08T14:50:36.981-07:00Website back!
The website
www.ammonoid.com
Fossil Cephalopods in Utah
is back up and running
Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-75268346598797384932017-07-20T08:19:00.000-06:002017-07-20T08:23:58.811-06:00Fish near the Early Triassic Equator!
Romano, C., Jenks, J., Jattiot, R., Scheyer, T., Bylund, K., & Bucher, H. 2017. Marine Early Triassic Actinopterygii from Elko County (Nevada, USA): Implications for the Smithian equatorial vertebrate eclipse. Journal of Paleontology, 1-22. doi:10.1017/jpa.2017.36
Abstract
The Early Triassic vertebrate record from low paleolatitudes is spotty, which led to the notion of an ‘Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-32737274127780803062017-04-28T09:29:00.000-06:002017-07-23T10:52:15.246-06:00An Early Triassic Starfish from Utah
The Starfish shortly after mechanical decomposition of a limestone slab in the field near Torrey, Utah.
Superstesaster promissor gen. et sp. nov., a new starfish (Echinodermata, Asteroidea) from the Early Triassic of Utah, USA, filling a major gap in the phylogeny of asteroids
Loïc Villier, Arnaud Brayard, Kevin G. Bylund, James F. Jenks, Gilles Escarguel, Nicolas Olivier, Daniel A. Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0tag:blogger.com,1999:blog-976017885885323343.post-47623749300813651762017-02-17T08:36:00.000-07:002017-02-17T08:50:08.604-07:00Unexpected Early Triassic marine ecosystem
Our latest work.
Artistic reconstruction of the Paris Biota. Artistic view of the early Spathian diversified and complex marine ecosystem of southeastern Idaho as revealed by the Paris Biota (with permission of Jorge Gonzalez).
A. Brayard, L. J. Krumenacker, J. P. Botting, J. F. Jenks, K. G. Bylund, E. Fara, E. Vennin,
N. Olivier, N. Goudemand, T. Saucède, S. Charbonnier, C. Romano, L. Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com3tag:blogger.com,1999:blog-976017885885323343.post-39650934455123378392016-12-31T15:44:00.001-07:002017-07-28T11:23:28.183-06:00Early Triassic Red BedsRed beds between the lowest ammonoid bearing limestones and the basal conglomerates. Commonly referred to the Black Dragon Formation (previously a member of the Moenkopi Fm.) or the Woodside Shale. Exposed all over Utah, SE Idaho and SW Wyoming.
In the San Rafael Swell the lowest (and only) Triassic Limestone contains the Anasibirites Fauna, so the red beds below are older than Late Kevin Bylundhttp://www.blogger.com/profile/07670968289144668213noreply@blogger.com0