rew Posted October 31, 2019 Author Share Posted October 31, 2019 I post 'em and piranha labels 'em. Link to comment Share on other sites More sharing options...
rew Posted November 1, 2019 Author Share Posted November 1, 2019 Now for the official trilobite of the week, #81. This is my last Ordovician proetid and the only Ordovician member of the Tropidocoryphidae in my collection -- Decoroproetus parviusculus from the Kope Formation of Bracken county, Kentucky. This is a rare bug. You can see a few museum specimens here: https://strata.uga.edu/cincy/fauna/trilobita/Decoroproetus.html I don't know of any other examples in a private collection. 5 Link to comment Share on other sites More sharing options...
rew Posted November 6, 2019 Author Share Posted November 6, 2019 Mid-week bonus trilobite #82 is Fragiscutum glebalis, an Encrinurid of Late Silurian age from the Henryhouse Formation in the Arbuckle Mountains of Pontotoc County, Oklahoma. 5 Link to comment Share on other sites More sharing options...
rew Posted November 6, 2019 Author Share Posted November 6, 2019 This bug has a face only a mother could love. 3 Link to comment Share on other sites More sharing options...
rew Posted November 9, 2019 Author Share Posted November 9, 2019 I still have the magnifying macro lens on my camera so I'm still doing small bugs. This one is a gem. The official trilobite of the week, #83, is the Early Devonian Acanthopyge consanguinea from the Bois d'Arc Formation of Black Cat Mountain, Clarita, Oklahoma. This is Bob Carroll's "Bug X". 6 1 Link to comment Share on other sites More sharing options...
rew Posted November 14, 2019 Author Share Posted November 14, 2019 Midweek bonus trilobite #84 is my smallest Cyphaspis trilobite, Cyphaspis carrolli from the Haragan Formation of Black Cat Mountain, Clarita, Oklahoma. This is Early Devonian in age. 4 Link to comment Share on other sites More sharing options...
rew Posted November 17, 2019 Author Share Posted November 17, 2019 I skipped #69 in my sequence of trilobites so this week's trilobite is #69. Some trilobites get to be preserved in a light cafe au lait color in near white limestone, like the Acanthopyge and Cyphaspides from Black Cat Mountain. But many, like this one, are stuck with dark gray shell on medium gray rock. Life isn't fair, and neither is death. This is an Early Ordovician Pliomerid trilobite from the Filmore Formation in Utah, Lemureops lemurei. 5 Link to comment Share on other sites More sharing options...
Jackson g Posted November 19, 2019 Share Posted November 19, 2019 On 11/17/2019 at 3:33 AM, rew said: I skipped #69 in my sequence of trilobites so this week's trilobite is #69. Some trilobites get to be preserved in a light cafe au lait color in near white limestone, like the Acanthopyge and Cyphaspides from Black Cat Mountain. But many, like this one, are stuck with dark gray shell on medium gray rock. Life isn't fair, and neither is death. This is an Early Ordovician Pliomerid trilobite from the Filmore Formation in Utah, Lemureops lemurei. Love pliomera trilobites. Is this the same species as Pseudocybele lemurei? Link to comment Share on other sites More sharing options...
piranha Posted November 19, 2019 Share Posted November 19, 2019 On 11/19/2019 at 7:58 AM, Jackson g said: Is this the same species as Pseudocybele lemurei? McAdams, N.E.B., Adrain, J.M. 2009 New pliomerid trilobite genus Lemureops from the Lower Ordovician (Ibexian; Tulean, Blackhillsian) of western Utah, USA. Memoirs of the Association of Australasian Palaeontologists, 37:491-540 PDF LINK "Hintze (1953) described Pseudocybele lemurei from the Fillmore Formation of western Utah. It is assigned herein to Lemureops gen. nov. ...Pseudocybele will be revised in detail in a forthcoming publication." McAdams, N.E.B., Adrain, J. M. 2010 A new species of the Lower Ordovician pliomerid trilobite Pseudocybele and its biostratigraphic significance. Zootaxa, 2550:21-38 PDF LINK "Pseudocybele" lemurei has been reassigned to the new genus Lemureops McAdams and Adrain, 2009a, which is the probable sister taxon of Pseudocybele." 5 Link to comment Share on other sites More sharing options...
fifbrindacier Posted November 19, 2019 Share Posted November 19, 2019 On 06/11/2019 at 9:49 PM, rew said: This bug has a face only a mother could love. "On ne voit bien que par le coeur, l'essentiel est invisible pour les yeux." (Antoine de Saint-Exupéry) "We only well see with the heart, the essential is invisible for the eyes." In memory of Doren Link to comment Share on other sites More sharing options...
rew Posted November 24, 2019 Author Share Posted November 24, 2019 I got tired of photographing itty bitty bugs so I put the regular macro lens back on and picked out one of my larger trilobites for this week. This week's trilobite, #85, is a Middle Silurian Homalonotid from the Rochester Shale of Middleport, New York, Trimerus delphinocephalus. This has the usual features of its family -- a concave face, small eyes, and a smooth carapace with nearly all trilobization lost, all adaptions for a life of burrowing in the mud. Like many other members of the Homalonotidae it is large, about 16.5 cm long. In life these trilobites had a high, domed carapace, but as is the case with most Trimerus specimens the carapace got crushed and flattened after the bug died. As it flattened, it spread out, while the edges got stuck in the mud. Something had to give, and the results are 90 degree breaks in the carapace at the edges. This is a common "failure mode" for Trimerus fossils. 3 Link to comment Share on other sites More sharing options...
rew Posted December 1, 2019 Author Share Posted December 1, 2019 Trilobite of the week #86 is one of those Bolivian "no prep" bugs -- they crack open a concretion, and if they're lucky they find a trilobite. This is Edredgeia eocryphaea, of Devonian age, in the family Calmoniidae. This trilobite is from the Belen Formation of Calamarca (La Paz) Bolivian Altiplano. The Calmoniidae are in the same superfamily as the Acastidae, and the resemblance is clear. Like other members of the Phacopina this has schizochroal eyes with easily visible lenses. 3 Link to comment Share on other sites More sharing options...
piranha Posted December 1, 2019 Share Posted December 1, 2019 The species is misspelled in the abstract and a figure description but the correct spelling listed in the systematic paleontology is: Eldredgeia eocryphaea Carvalho, M.D.G.P., Edgecombe, G.D., Smith, L. 2003 New Calmoniid Trilobites (Phacopina: Acastoidea) from the Devonian of Bolivia. American Museum of Natural History, Novitates, 3407:1-17 PDF LINK 3 Link to comment Share on other sites More sharing options...
rew Posted December 1, 2019 Author Share Posted December 1, 2019 Okay, corrected. Thanks Link to comment Share on other sites More sharing options...
rew Posted December 6, 2019 Author Share Posted December 6, 2019 Trilobite of the week #87 is a humble Middle Ordovician Asaphid from Builth Inlier, Wales: Ogygiocarella debuchi. The specimen here has the typical flattened preservation. The main claim to fame of this bug is that it is the first trilobite to be given a scientific description, in 1698 in the Philosophical Transactions of the Royal Society. The author suggested that it was a type of flat fish. 4 1 Link to comment Share on other sites More sharing options...
rew Posted December 11, 2019 Author Share Posted December 11, 2019 Midweek bonus trilobite #88 is Asaphus punctatus, a Middle Ordovician asaphid from Vilpovitsy quarry near St. Petersburg, Russia. This bug goes beyond the "frog eyes" of A. cornutus and has moderate sized, robust eye stalks. 7 Link to comment Share on other sites More sharing options...
rew Posted December 11, 2019 Author Share Posted December 11, 2019 There are two midweek bonus trilobites this time. #89 is Asaphus intermedius, also of Middle Ordovician age and from the Vilpovitsy quarry near St. Petersburg, Russia. This has proportionately longer eye stalks than A. punctatus. 6 Link to comment Share on other sites More sharing options...
rew Posted December 11, 2019 Author Share Posted December 11, 2019 One thing about doing these photographs -- I see details I didn't see before. The Asaphus intermedius in the only member of the Asaphidae in my collection where I can seen the lenses of the holochroal eyes. 7 1 Link to comment Share on other sites More sharing options...
rew Posted December 13, 2019 Author Share Posted December 13, 2019 Well, by now I'm sure you can all guess what the official trilobite of the week, #90 is -- everybody's favorite Asaphus trilobite -- Asaphus kowalewskii, of Middle Ordovician age and from the Vilpovitsy quarry, Asery Level, in the St Petersburg region, Russia. As you can see, those crazy eye stalks didn't come from nowhere -- there were many Asaphus species with varying sizes of eye stalks, some in my collection and some not. A. kowalewskii is just the most extreme of the lot. Most likely the eye stalks were there to let the trilobite see while buried in the mud. It may have been a stealth predator, waiting for some unwary victim to walk by before leaping out and grabbing it. 7 Link to comment Share on other sites More sharing options...
rew Posted December 20, 2019 Author Share Posted December 20, 2019 Trilobite of the week #91is another member of the Acastidae, a trilobite family I never seem to run out of examples of. This is the Early Devonian trilobite Coltraneia oufatenensis, from Hamar Laghdad, Morocco. This bug has large eyes. 4 Link to comment Share on other sites More sharing options...
rew Posted December 21, 2019 Author Share Posted December 21, 2019 "If you gaze long into an abyss, the abyss will also gaze into you." -- Nietzsche. 2 Link to comment Share on other sites More sharing options...
rew Posted December 28, 2019 Author Share Posted December 28, 2019 Trilobite of the week #92 is a Middle Devonian harpetid from the Tazoulait Formation of Boudib, Morocco that is generally placed in the genus Scotoharpes. I don't think it has a formal description yet. This specimen is essentially prone, most have some degree of enrollment. You can see many of the small pits in the head shield; it is believed that these may have contained small hairs that detected vibrations and sound, compensating for the poor vision of the small eyes. 2 Link to comment Share on other sites More sharing options...
piranha Posted December 28, 2019 Share Posted December 28, 2019 6 hours ago, rew said: Trilobite of the week #92 is a Middle Devonian harpetid from the Tazoulait Formation of Boudib, Morocco that is generally placed in the genus Scotoharpes. I don't think it has a formal description yet. This specimen is essentially prone, most have some degree of enrollment. You can see many of the small pits in the head shield; it is believed that these may have contained small hairs that detected vibrations and sound, compensating for the poor vision of the small eyes. This one is Harpes perradiatus Richter & Richter 1943. Another similar species recently described: Harpes hamarlaghdadensis Crônier et al. 2018 is differentiated by a subrectangular glabella versus the conical glabella illustrated well in your excellent textbook example. Richter, R., Richter, E. 1943 Trilobiten aus dem Devon von Marokko mit einem Anhang über Arten des Rheinlandes. [Trilobites from the Devonian of Morocco with an appendix about the Rhineland species.] Senckenbergiana Lethaea, 26:116-198 Crônier, C., Oudot, M., Klug, C., De Baets, K. 2018 Trilobites from the Red Fauna (latest Emsian, Devonian) of Hamar Laghdad, Morocco and their Biodiversity. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen, 290(1-3):241-276 PDF LINK 3 Link to comment Share on other sites More sharing options...
rew Posted December 29, 2019 Author Share Posted December 29, 2019 This is one of those things that has had me confused -- some sellers call these bugs Scotoharpes sp., others have a trilobite that looks essentially the same called Harpes perradiatus. I was trying to figure out if there was some subtle difference between the two that I was missing. Apparently the Moroccan bugs called "Scotoharpes sp." are just misnamed. Link to comment Share on other sites More sharing options...
piranha Posted December 29, 2019 Share Posted December 29, 2019 Yes, more erroneous internet info. The stratigraphic range for Scotoharpes is Ordovician-Silurian. 2 Link to comment Share on other sites More sharing options...
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