Trilo-bottoms

[Kane]

As I prepare a space in the dining room for a large trilobite display, organized by geologic periods and taxonomic trees, I am also cleaning up the database and trying to pinpoint some IDs with a bit more precision, and would definitely be grateful for assistance.

 

The first two are pictured in the first image.

 

On the left is a find from my area with the imported fill, so it could be anything from Bois Blanc, Amherstberg, to Dundee Fms. I am thinking that this is a dalmantid, along the lines of Anchiops due to what appear to be incised axial rings and that wide, flaring upper portion of the pygidium. But I am not 100% sure. If it is A. anchiopsis, it goes in my "to trade" pile as I already have examples of this one. 

 

On the right is a gift from John B. and his trip to Wrens Nest with the challenge to prep it out a bit more. The matrix of this stuff laughed at my air scribe as it whined and whined with very little give. I was vaguely thinking Dalmanites myops. Hopefully there is enough detail to be certain. It lacks the pygidial spike if that is the case. I am having some difficulty locating any of my literature on Wrens Nest bugs at the moment.

 

The third is another odd find from my import fill area. It has a pygidial border, that puts me in mind of Pseudodechenella, but it does not seem quite right. The axis tapers to a point and sits high up when viewed from the side. Scale of the tiny squares is 5mm x 5mm.

 

[Kane]

And, while I'm here and cleaning up, this trio as well. I've tinkered with them to uncover matrix, but put them aside in a bin. Also from the same Devonian potpourri mix:

[Miocene_Mason]

Nice pygidia, this seems like a job for @piranha

[JohnBrewer]

1 hour ago, Kane said:

a gift from John B. and his trip to Wrens Nest with the challenge to prep it out a bit more. The matrix of this stuff laughed at my air scribe as it whined and whined with very little give

Always have the same problem Kane. Matrix is crazily hard. The trilos are pretty resilient too but I think matrix has one over.  I might try something chemical. I’ve got some fossil free slabs and might see what I can do. Bet it laughs at hydroflouric acid. NOT that I’m gonna go that route even tho I’m stupid.....

[Kane]

1 minute ago, JohnBrewer said:

Always have the same problem Kane. Matrix is crazily hard. The trilos are pretty resilient too but I think matrix has one over.  I might try something chemical. I’ve got some fossil free slabs and might see what I can do. Bet it laughs at hydroflouric acid. NOT that I’m gonna go that route even tho I’m stupid.....

The funny thing is, there are "softer" parts that cooperate, but on the whole even a liberal dousing of HP sauce doesn't seem to loosen it.  When you wished me luck, you weren't kidding! But, you are right that the trilo is quite resilient (thankfully) although I doubt I will want to take too brute a risk with this one.

[piranha]

Calymene blumenbachi

 

[Kane]

48 minutes ago, piranha said:

Calymene blumenbachi

 

Perfect! My thanks... Have to correct the database! (my guess was way off, but at least I got the phacopid part correct  ).

 

I seem to be coming up short on plates for the lower-mid Devonian pygidia. I have a few select articles by Ludvigsen et al., and the Trilobite treatise, but can't seem to match up the images to the specimens. 

 

...Also no luck in raiding my stores of Stumm's proetids, and no precise matches in Trilobites of NY, nor Ludvigsen's short Fossils of Ontario (or even my Formosa Reef stuff).  

 

 

[Tidgy's Dad]

40 minutes ago, piranha said:

Calymene blumenbachi

 

,Much as I hate to be pedantic, but shouldn't that be Calymene blumenbachii ? 

Or have they changed that as well?

[piranha]

14 minutes ago, Tidgy's Dad said:

,Much as I hate to be pedantic, but shouldn't that be Calymene blumenbachii ? 

Or have they changed that as well?

 

 

I missed an 'i' with my copy and paste.  Anything else?  lol  

[piranha]

1 hour ago, Kane said:

(my guess was way off, but at least I got the phacopid part correct  ).

 

 

All from the Order 'Phacopida', however, Dalmanites is a dalmanitid (Dalmanitidae) and Calymene is a calymenid (Calymenidae). 

[Kane]

Aye, and that I should have known.  Just about all my calymenids have those "droopy" pygidial furrows (yes, that will be my fancy technical term. ). 

[Tidgy's Dad]

1 hour ago, piranha said:

 

 

I missed an 'i' with my copy and paste.  Anything else?  lol  

Erm. 

Okay, it's interesting to note that not only are Dalmanites and Calymene members of different families, but different suborders. Dalmanites is a member of the suborder Phacopina and Calymene from the suborder Calymenina. 

[piranha]

Today I took a break from my usual data gathering routine to investigate the case of the missing 'i' in Calymene blumenbachii 

From the original description of Brongniart 1822, there are approximately 205 papers with C. blumenbachii from 1822-2018.

Elrathia kingii appears to have similar statistics, but that research will have to wait for another day!   

 

 

taxonomic history:

Entomolithus paradoxus Linnaeus 1759

Trilobus tuberculatus Brünnich 1781

Trilobites tuberculatus Blumenbach 1810

Entomolithus paradoxus Parkinson 1811

Entomostracites tuberculatus Wahlenberg 1818

Entomolithes tuberculatus Wahlenberg 1821

Calymene blumenbachii Brongniart 1822

 

This list in chronological order by publication date shows 72 papers (35%) have been published with the missing 'i'. 

 

Murchison, Roderick Impey 1845. 
On the Palaeozoic Deposits of Scandinavia and the Baltic Provinces of Russia, and their relations to Azoic or more ancient crystalline Rocks; with an account of some great features of dislocation and metamorphism along their northern frontiers.
Quarterly Journal of the Geological Society of London 1:467-494

 

Rouault, Marie 1847.
Extrait du Mémoire sur les Trilobites du Département d'Ille-et-Villaine. 
Bulletin de la Société Géologique de France, 2nd Series, 4:309-328

 

Rouault, Marie 1849. 
Mémoire 1° sur la composition du test des Trilobites; 2° sur les changements de formes dus a des causes accidentelles, ce qui a pu permettre de confondre des espèces différentes.
Bulletin de la Société Géologique de France, 2nd Series, 6:67-89

 

Sedgwick, Adam & McCoy, Frederick 1851. 
A synopsis of the classification of the British Palaeozoic rocks, with a systematic description of the British Palaeozoic fossils found in the geological museum of the University of Cambridge

 

Eichwald, Edouard von 1857. 
Beitrag zur Geographischen Verbreitung der fossilien Thiere Russlands. Alte Period.
Bulletin de la Société Impériale des Naturalistes de Moscou 30(2):305-338

 

Nieszkowski, Johannes 1859. 
Zusätze zum Monografie über die Trilobiten die Ostseeprovinzen, nebst der Beschreibung einer neuen obersilurischen Crustaceen.
Archiv für die Naturkunde Liv-, Ehst-und Kurlands 2(2):345-384

 

Bronn. H.G. 1861. 
Demonstration of theoretical laws by research on fossil organized bodies contained in sedimentary layers.
Comptes Rendus Hebdomadaires des Séances de l'Academie des Sciences 53(Sup.):570-601

 

Billings, E. 1866. 
Catalogues of the Silurian fossils of the island of Anticosti: with descriptions of some new genera and species. 
Geological Survey of Canada

 

Barrande, Joachim 1871. 
Trilobites. Extrait du Supplément au Vol. 1. du Systême Silurien du centre de la Bohême.

 

Barrande, Joachim 1872. 
Systême Silurien du centre de la Bohême. 1 ère Partie. Recherches paléontologiques, 
Supplement au Vol.I: Trilobites, Crustaces divers et Poissons.  (Prague and Paris).

 

Törnquist, Sven Leonhard 1884. 
Undersökningar öfver Siljansområdets trilobitfauna. 
Sveriges Geologiska Undersökning, Serie C, 66:1­-101

 

Novák, Ottomar 1885. 
Studien an Hypostomen böhmischer Trilobiten, II.

[Studies of Bohemian Trilobite Hypostomes, II.]
Zprávy o Zasedání Královské Ceske Společnosti Nauk v Praze Rocník 1884:212-229

 

Pfeiffer, P.A. 1888
Die Palaeozoischen Arthropoden in der Sternwarte zu Kremsmünster.
[The Palaeozoic Arthropods in the Observatory at Kremsmünster.]
Jahresberichte des Vereins für Naturkunde in Österreich ob der Enns zu Linz, 18:1-14

 

Reed, F.R.C. 1896. 
The fauna of the Keisley Limestone, Part I. 
Quarterly Journal of the Geological Society of London 52:407-437

 

Reed, F.R.C.. 1897. 
The fauna of the Keisley Limestone, Part II. 
Quarterly Journal of the Geological Society of London 53:67-106

 

Reed, F.R.C. 1899. 
The lower Palaeozoic bedded rocks of County Waterford.
Quarterly Journal of the Geological Society of London 55:718-772

 

Peach, B.N.; Horne, J.; Macconochie, A. 1904. 
The Silurian Rocks in the South of Scotland.
Geological Society, Glasgow. 1901:423-444

 

Peach, B.N. 1904. 
The Trilobites of the Silurian Rocks of Southwest Scotland.
Geological Society, Glasgow. 1904:445-447

 

Peach, B.N. 1904. 
The Arthropoda from the Silurian Rocks of Southwest Scotland.
Geological Society, Glasgow. 1904:450-453

 

Reed, F.R.C. 1906.
The Lower Palaeozoic Trilobites of the Girvan District, Ayrshire. 
Palaeontographical Society, London 286:97-186

 

Prouty, William F. 1908. 
The Meso-Silurian Deposits of Maryland.
American Journal of Science, Series 4, 26:563-574

 

Richter, Rudolf & Richter, Emma 1914. 
Von unseren Trilobiten. 
Bericht der Senckenbergischen Naturforschenden Gesellschaft 45:50-62

 

Kerforne, F. 1914. 
Sur la présence de Calymmene blumenbachi Brongn. dans le Gothlandien de Bretagne.
Comptes rendus Hebdomadaires des Séances de l'Académie des Sciences 158:1458-1459

 

Kerforne, F. 1923. 
Etude stratigraphique de la vallée de l'Ille entre Saint-Médard-sur-Ille et Saint- Germain-sur-Ille (Ille-et-Vilaine).
Bulletin de la Société géologique et minéralogique de Bretagne 1923:178-191

 

Gardiner, Charles Irving 1927. 
The Silurian Inlier of Woolhope, Herefordshire. 
Quarterly Journal of the Geological Society of London 83:501-530

 

Reed, F.R.C. 1931. 
The Lower Palaeozoic Trilobites of the Girvan District, Ayrshire. Supplement 2: A Revision of Some Species Previously Described.
Palaeontographical Society,London 382:1-29

 

Whittard,  Walter Frederick 1932. 
The Stratigraphy of the Valentian Rocks of Shropshire. The Longmynd-Shelve and Breidden Outcrops.
Quarterly Journal of the Geological Society of London 88:859-902

 

Cayeux, L. 1933. 
Rôle des Trilobites dans la genèse des gisements de phosphate de chaux paléozoïques.
Comptes rendus Hebdomadaires des Séances de l'Académie des Sciences 196:1179-1182

 

Shirley, J. 1936. 
Some British trilobites of the family Calymenidae. 
Quarterly Journal of the Geological Society of London 92(14):384-422

 

Stubblefield, C.J. 1936. 
Cephalic sutures and their bearing on current classification of trilobites. 
Biological Reviews 11(4):407-440

 

Bouček, Bedřich 1937. 
Stratigraphie et parallélisme de l'Ordovicien supérieur de la Bohême.
Bulletin de la Société Géologique de France, 5th series, 7:439-458

 

Philipott, André 1950. 
Les Graptolites du Massif Armoricain. Etude Stratigraphique et Paléontologique.
Mémoires Société géologique et minéralogique de Bretagne 8:1-295

 

Williams, Alwyn 1952. 
The geology of the Llandello district, Carmarthenshire. 
Quarterly Journal of the Geological Society of London 108:177-207

 

Přibyl, Alois 1953. 
Index of trilobite genera in Bohemia.
Knihovna Ústředního Ústavu Geologického 25:1-80

 

Harrington, Horacio J. 1956. 
Argentina. In: Handbook of South American Geology: An Explanation of the Geologic Map of South America.
Geological Society of America Memoir 65:129-166

 

McKerrow, W.S.; Blackburn, Audrey L.; Taylor, S.R. 1956. 
Rare alkali elements in trilobites. 
Geological Magazine 93:504-516

 

Maksimova, Zlata Aleksandrovna 1960. 
Silurian system. Class Trilobita.
Trudy Sibirskogo Nauchno-Issledovatel'skogo Instituta Geologii, 20:117-120,178

 

Maksimova, Zlata Aleksandrovna 1960. 
Palaeontological base for the Palaeozoic stratigraphy of the Rudny Altai. Devonian and Carboniferous trilobites of the Rudny Altai.
Vsesoyuznogo Nauchno-Issledovatel'skogo Geologicheskogo Instituta (VSEGEI), N.S., 1-123

 

Freshney, E.C. 1960. 
An Extension of the Silurian Succession in the Craighead Inlier, Girvan. 
Transactions of the Geological Society of Glasgow 24(1):27-31

 

Barlier, Jacques; Le Maître, Dorothée; Rogier, Phillipe 1960. 
Presence of the genera Ampyx and Plumulites in the Gothlandian of the northeastern border of Tassili N 'Adjer: Adrar Ikohahoène (Fort de Polignac Basin).
Comptes Rendus Hebdomadaires des Séances de l'Academie des Sciences 250:4407-4409

 

Guo Hongjun 1962. 
Some Silurian Trilobites from the Er-Tao-Gou Group of Jilin.
Acta Palaeontologica Sinica 10(3):369-385

 

Dean, William Thornton 1963. 
The Stile End beds and Drygill shales (Ordovician) in east and north of the English Lake District.
Bulletin of the British Museum (Natural History), Geology Series, 9(3):47-65

 

Sutton, I.D. 1966. 
The Geology of Sedgley and Dudley. 
The Mercian Geologist 2:112-114

 

Gratsianova, R.T. 1967. 
Brachiopods and stratigraphy of the lower Devonian Gorny Altai.
Akademiya Nauk SSSR, Sibirskoe Otdelenie, Instituta Geologii i Geofiziki (Moscow) 175 pp.

 

Kylkov, N.P. 1967. 
Silurian brachiopods and stratigraphy of Altai Mountain.
Akademiia Nauk SSSR, Sibirskoe Otdelenie, Instituta Geologii i Geofizikii (Moscow) 151 pp.

 

Ëlkin, Evgenii Aleksandrovich 1968. 
Trilobites (Dechenellidae) and stratigraphy of the Lower and Middle Devonian of the South of West Siberia.
Akademiya Nauk SSSR, Sibirskoe Otdelenie, Instituta Geologii i Geofiziki (Moscow) pp.80-146

 

Schrank, Eckart 1970. 
Calymeniden (Trilobita) aus silurischen Geschieben.
Berichte der Deutschen Gesellschaft für Geologische Wissenschaft, A: Geol.Pal. 15(1):109-146

 

Curtis, M.L.K. 1972. 
The Silurian rocks of the Tortworth Inlier, Gloucestershire.
Proceedings of the Geologists' Association 83(1):1-35 

 

British Palaeozoic Fossils, 1975. 
British Museum, Butler and Tanner Ltd., 4th Ed.

 

Walmsley, Victor G. & Bassett, Michael G. 1976. 
Biostratigraphy and correlation of the Coralliferous Group and Gray Sandstone Group (Silurian) 
of Pembrokeshire, Wales. Proceedings of the Geologists' Association 87(2):191-220

 

McNamara, K J. 1979. 
The age, stratigraphy and genesis of the Coniston Limestone Group in the southern Lake District. 
Geological Journal 14(1):41-68

 

Neben, W. & Krueger, Hans-Hartmut 1979. 
Fossilien Kambrischer, Ordovizischer und Silurischer Geschiebe. 
Staringia No.5, Grondboor en Hamer 33(1):3-63

 

Maksimova, Zlata Aleksandrovna 1980. 
Biostratigraphic zones based on trilobites in USSR Devonian deposits. 
International Geology Review 22(4):477-489 

 

Kobayashi, Teiichi 1981. 
The Geological History of the Eastern Part of the Mongolian Geosyncline.
Journal of Geography 90(6):424-432

 

Männil, Reet 1982. 
Wenlock and late Silurian trilobite associates of the East Baltic area and their stratigraphical value.
Eesti NSV Teaduste Akadeemia Toimetised, Geoloogia 31:63-70

 

Tống Duy Thanh 1982. 
Biostratigraphic significance complexes fauna in Devonian region Beibu (Vietnam).

 

Schöning, Heinrich 1983.
Neue Trilobitenfunde aus dem Geschieben des Kies-Sand-Rückens «Laer Heide» bei Bad Laer a.T.W.
Der Geschiebesammler 16(2):57-69

 

Jeppsson, Lennart & Laufeld, Sven 1986. 
The late Silurian Öved-Ramsåsa Group in Skåne, south Sweden.
Sveriges Geologiska Undersökning, Serie Ca, 58:1-45

 

Tống Duy Thanh;  1986. 
Hệ Devon Ở Việt Nam. Devonian In Vietnam System.

 

Paškevičius, J. 1986. 
Assemblages of Silurian graptolites in various facies of the East Baltic region.
Geological Society of London, Special Publication 20:237-245

 

Kobayashi, Teiichi 1988. 
Relation between the Silurian trilobites of Japan and the Mongolian geosyncline.
Proceedings of the Japan Academy, Ser.B, 64(4):81-84 

 

Dubatolov, V.N. & Tesakov, Yu.I. 1988. 
Devonian stratigraphy and Coelenterata of Vietnam. Vol. 1. Stratigraphy.
Akademiya Nauk SSSR, Sibirskoe Otdelenie, Instituta Geologii i Geofiziki (Novosibirsk) 179 pp.

 

Wilmot, Nadine Vivienne 1988. 
Design and function of trilobite exoskeletons. 
PhD Thesis, University of Aston in Birmingham, 207 pp.

 

Kowalski, Heinz 1992.
Trilobiten. Verwandlungsküntsler des Paläozoikums: ein unorthodoxer Streifzug durch das Reich der Dreilapper. 
Goldschneck-Verlag. 157 pp.

 

Malvesy, T; Morzadec, P.; Feist, R. 1999. 
Collections du Musée d'Histoire Naturelle de Lille I. — Les Trilobites (types et figures).
Annales de la Société géologique du Nord, Ser.2, 6:157-162

 

Štorch, Petr & Massa, Dominique 2006. 
Middle Llandovery (Aeronian) graptolites of the western Murzuq Basin and Al Qarqaf Arch region, south-west Libya.
Palaeontology 49(1):83-112

 

Konstantynenko, Leonid 2007. 
Calymenidae (Trilobita) of the Silurian of the Podillya.
Geological Science Institute of NASU, Paleontological Collection 39:10-19

 

Ray, David C. & Thomas, A.T. 2007. 
Carbonate depositional environments, sequence stratigraphy and exceptional skeletal preservation in the much Wenlock limestone Formation (Silurian) of Dudley, England. Palaeontology 50(1):197-222

 

Donovan, Stephen K. 2012. 
British Wenlock crinoids at the Western Australian Museum. 
Proceedings of the Shropshire Geological Society 17:12-16

 

Männik, Peep & Nestor, Viiu 2014. 
Field Guide. Stop B5: Panga cliff.
4th Annual Meeting of IGCP 591, The Early to Middle Paleozoic Revolution, Estonia

 

Mesentseva, Olga P. & Gumerova, Nina V. 2014. 
Fossils and stratigraphic units of the Emsian deposits in Baragash Trough (Gorny Altai).
Bulletin of the Tomsk State University 378:219-223

 

Levi-Setti, Riccardo 2014.
The Trilobite Book. A Visual Journey. 
University of Chicago Press 273 pp.

[Tidgy's Dad]

20 hours ago, piranha said:

Today I took a break from my usual data gathering routine to investigate the case of the missing 'i' in Calymene blumenbachii 

From the original description of Brongniart 1822, there are approximately 205 papers with C. blumenbachii from 1822-2018.

Elrathia kingii appears to have similar statistics, but that research will have to wait for another day!    

 

 

taxonomic history:

Entomolithus paradoxus Linnaeus 1759

Trilobus tuberculatus Brünnich 1781

Trilobites tuberculatus Blumenbach 1810

Entomolithus paradoxus Parkinson 1811

Entomostracites tuberculatus Wahlenberg 1818

Entomolithes tuberculatus 1821

Calymene blumenbachii Brongniart 1822

 

 

Goodness! 

Very thorough. 

But how many that use one i are accidents, or is that standard in those papers ?

It is still surprisingly often mentioned with just the one i. 

I look forward to the Elrathia kingii (kingi, ahem) version, especially as I just prepped a few. 

[piranha]

15 hours ago, Tidgy's Dad said:

But how many that use one i are accidents, or is that standard in those papers ?

It is still surprisingly often mentioned with just the one i. 

Unfortunately they are simply standard mistakes, the 'standard' is supposed to be accuracy. 

But perhaps others just preferred to use one 'i' in spite of the obvious priority of Brongniart.

 

 

15 hours ago, Tidgy's Dad said:

I look forward to the Elrathia kingii (kingi, ahem) version, especially as I just prepped a few. 

I was only kidding, once was enough, that is way too much effort for such a trivial pursuit!

 

 

More interesting fun facts about Calymene blumenbachii can be found in this paper:

 

Mikulic, D.G., & Kluessendorf, J. (2007)

Legacy of the Locust - Dudley and its famous trilobite: Calymene blumenbachii 

 

In: Mikulic, D.G., Landing, E., & Kluessendorf, J, eds. (2007)

Fabulous Fossils: 300 Years of Worldwide Research on Trilobites.

New York State Museum Bulletin: 507:1-248   PDF LINK

 

 

Calymene blumenbachii was also involved in an infamous scandal, described by Woodward 1868 as a new species with long eye-stalks: ‘Calymene ceratophthalma’

 

 

Woodward, H., (1868)

On a newly-discovered long-eyed Calymene from the Wenlock Limestone, Dudley.

Geological Magazine 5:489-493

 

 

Following a swift rebuke from his peers, he was forced to retract his dubious species.

 

Woodward, H. (1869)

On a newly-discovered long-eyed trilobite from Dudley.

Geological Magazine 6:43-44

[Tidgy's Dad]

1 hour ago, piranha said:

Unfortunately they are simply standard mistakes, the 'standard' is supposed to be accuracy. 

But perhaps others just preferred to use one 'i' in spite of the obvious priority of Brongniart.

 

 

I was only kidding, once was enough, that is way too much effort for such a trivial pursuit!

 

 

More interesting fun facts about Calymene blumenbachii can be found in this paper:

 

Mikulic, D.G., & Kluessendorf, J. (2007)

Legacy of the Locust - Dudley and its famous trilobite: Calymene blumenbachii 

 

In: Mikulic, D.G., Landing, E., & Kluessendorf, J, eds. (2007)

Fabulous Fossils: 300 Years of Worldwide Research on Trilobites.

New York State Museum Bulletin: 507:1-248   PDF LINK

 

 

Calymene blumenbachii was also involved in an infamous scandal, described by Woodward 1868 as a new species with long eye-stalks: ‘Calymene ceratophthalma’

 

 

Woodward, H., (1868)

On a newly-discovered long-eyed Calymene from the Wenlock Limestone, Dudley.

Geological Magazine 5:489-493

 

 

Following a swift rebuke from his peers, he was forced to retract his dubious species.

 

Woodward, H. (1869)

On a newly-discovered long-eyed trilobite from Dudley.

Geological Magazine 6:43-44

Thank you very much indeed. I have the Legacy of the Locust one. 

I shall enjoy reading the rest of these.

Mr Woodward was fooled by a workman's fake it seems! Heard of this but never read the papers.

Thanks again. 

[Tidgy's Dad]

For those who are interested in such things, Calymene blumenbachii is featured on the Coat of Arms of Dudley.

You can see the trilobite on the white band in the middle. 

[JohnBrewer]

On 13/02/2018 at 11:17 PM, Kane said:

The funny thing is, there are "softer" parts that cooperate, but on the whole even a liberal dousing of HP sauce doesn't seem to loosen it.  When you wished me luck, you weren't kidding! But, you are right that the trilo is quite resilient (thankfully) although I doubt I will want to take too brute a risk with this one.

This is a useful book @Kane http://www.nhmshop.co.uk/british-palaeozoic-fossils.html

 

 

[JohnBrewer]

On 13/02/2018 at 11:30 PM, piranha said:

Calymene blumenbachi

 

Not Acaste sp. then? They’re really common there. All the Calymene I’ve found there are much bigger but there is an abundance of these really small ones which I thought were Acaste rather than juvenile Calymene. Not that I know anything trilo collecting ichthyosaur material mainly......

[piranha]

6 minutes ago, JohnBrewer said:

Not Acaste sp. then? They’re really common there. All the Calymene I’ve found there are much bigger but there is an abundance of these really small ones which I thought were Acaste rather than juvenile Calymene. Not that I know anything trilo collecting ichthyosaur material mainly......

 

 

Acaste does not have a large terminal axial piece.  Look again at the scale Kane provided, the pygidium is ~2 cm wide, a typical size for a large Calymene.  

 

[JohnBrewer]

11 minutes ago, piranha said:

 

 

Acaste does not have a large terminal axial piece.  Look again at the scale Kane provided, the pygidium is ~2 cm wide, a typical size for a large Calymene.  

 

Thanks @piranha  I must have been rather generous sending @Kane such a large trilo! Or maybe I thought it was small and Kane has exposed more than I thought was there. I do find many small which I thought maybe Acaste. Having re-looked at this thread I think it was the trilo I thought was Calymene I sent Kane 

 

[Kane]

And that leaves the other half dozen trilo-butts to pin down. I am guessing that the one on the left of the C. blumenbachii is a dalmanitid? Another Anchiopsis? The one below appears to be a proetid of some type, but lacks the kind of "glaze" covering of Pseudodechenella (plus that bizarre tapering axial piece), and not a thick enough border to be Crassiproetus.

 

I'll put this out there: would anyone know of any articles on Devonian proetidae (and/or dalmanitids) in Ontario, apart from Ludvigsen's piece on the Formosa Reef? And, of course, hopefully ones containing photo plates. My database searches are coming up empty, which either means there are no articles that drill down to this particular subject, or the databases I am using are woefully incomplete. I'll do another search, but any help in tracking down the proper literature would help me out greatly!

 

Just going through Lieberman's 1994 text on Eastern North American proetids, and hopeful to come up with a match.

[piranha]

These papers have a bunch of Canadian dalmanitids and dechenellids for comparison:

 

Ormiston, A.R. (1967)
Lower and Middle Devonian Trilobites of the Canadian Arctic Islands. 
Geological Survey of Canada Bulletin, 153:1-148

 

Lesperance, P.J. & Bourque, P.A. (1971)
The Synphoriinae: An Evolutionary Pattern of Lower and Middle Devonian Trilobites.
Journal of Paleontology, 45(2):182-208

 

Lesperance, P.J. (1975)
Stratigraphy and Paleontology of the Synphoriidae (Lower and Middle Devonian Dalmanitacean Trilobites).

Journal of Paleontology, 49(1):91-137

 

Lespérance, P.J. & Sheehan, P.M. (1988)
Faunal assemblages of the Upper Gaspé  Limestones, Early Devonian of eastern Gaspé, Quebec. 
Canadian Journal of Earth Sciences, 25(9):1432-1449

 

Check your email - files sent! 

[piranha]

On 2/13/2018 at 1:52 PM, Kane said:

On the left is a find from my area with the imported fill, so it could be anything from Bois Blanc, Amherstberg, to Dundee Fms. I am thinking that this is a dalmantid, along the lines of Anchiops due to what appear to be incised axial rings and that wide, flaring upper portion of the pygidium. But I am not 100% sure. If it is A. anchiopsis, it goes in my "to trade" pile as I already have examples of this one. 

 

Agree: Anchiopsis anchiops

 

 

On 2/13/2018 at 1:52 PM, Kane said:

The third is another odd find from my import fill area. It has a pygidial border, that puts me in mind of Pseudodechenella, but it does not seem quite right. The axis tapers to a point and sits high up when viewed from the side. Scale of the tiny squares is 5mm x 5mm.

 

The axis appears to be distorted by lateral compression. 

Eldredgeops rana with similar characteristics of distortion:

[Kane]

@piranha: My double thanks. A delightful trove that will be helpful to me in the field, and for the ID assist. I do have just one from Lespérance, so this is an added treat. 

 

I honestly hadn't considered compression to account for that shape.