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Heliophyllum?


Cassandra Tiensivu

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Cassandra Tiensivu

Hello everyone. My daughter found this today on a beach in Alpena. We know it’s a coral, and so far, two folks suspect it is possibly Heliophyllum. I’m unfamiliar with that species and have nothing to compare it to. Just wondering if anyone else has seen something similar? 
 

 

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B5B526CF-B6ED-46D1-AF42-46EB8EAB7002.jpeg

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FossilDAWG

I don't think it is a Heliophyllum.  That genus has characteristic "yard-arm carinae" developed on the septa.  These are short spiky structures on opposite sides of the septa, that sort of resemble yard-arms (the horizontal beams sails attach to) on sailing ship masts.

 

Unfortunately confident identification of corals usually requires cutting thin sections to reveal the internal structures.  It might be possible to make an "educated guess", though, based on the formation and location.

 

Heliophyllum.jpg

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41 minutes ago, FossilDAWG said:

I don't think it is a Heliophyllum.  That genus has characteristic "yard-arm carinae" developed on the septa.  These are short spiky structures on opposite sides of the septa, that sort of resemble yard-arms (the horizontal beams sails attach to) on sailing ship masts.

 

Unfortunately confident identification of corals usually requires cutting thin sections to reveal the internal structures.  It might be possible to make an "educated guess", though, based on the formation and location.

 

Heliophyllum.jpg


Thank you!
 

I’ve circled on the map the general location as to where she found it (in Thunder Bay / Alpena). 

4EE47ED8-E5CB-484A-8721-EC0681F18E6B.png

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piranha
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Ehlers, G.M., Kesling, R.V. 1970

Devonian Strata of Alpena and Presque Isle Counties, Michigan. Guidebook for Field Trips.
Michigan Basin Geological Society, Geological Society of America, North-Central Section Meeting, 130 pp.  PDF LINK

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1 hour ago, FossilDAWG said:

I don't think it is a Heliophyllum.  That genus has characteristic "yard-arm carinae" developed on the septa.  These are short spiky structures on opposite sides of the septa, that sort of resemble yard-arms (the horizontal beams sails attach to) on sailing ship masts.

 

Unfortunately confident identification of corals usually requires cutting thin sections to reveal the internal structures.  It might be possible to make an "educated guess", though, based on the formation and location.

 

Heliophyllum.jpg

 

 

Could these be worn yard-arm carinae? They're not as prominent as in the example above, but there do appear to be some carinae present.

 

 image.png.e7e6602f6449c81885f3a1c83b7839aa.png

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On 7/24/2021 at 2:37 AM, Cassandra Tiensivu said:

A friend finally came up with the right ID! Naos ponderosum! 

 

http://michiganbasinfossils.org/viewrecord/1327

 

 

EDIT: Actually, with more photos, this is looking distinctly naotic and Naos or Chondrophyllum (both rather uncertain genera, at least partly synonymous) look to be good IDs). See discussion further down.

 

I'm not at all sure about that, Cassandra.  It may be the same species as in the link, though I think @LisaL may be right and yours may have carinae, while that one apparently doesn't. :)  

You can't really ID corals reliably without sections though - external similarities aren't enough.  

Neither of them seems to be Naos.

 

To be Naos, it should have closely spaced dissepiment-like plates in the periphery with zig-zag septa that break up up in that region which there's no sign of there.

Also, according to the Treatise, Naos is a questionable genus anyway, only possibly present in the north American continent in the Silurian - and only listed at all from Arctic Canada, where the lectotype comes from.

Like many genera, it has probably been been applied to various things in the past that don't go with the diagnosis.

 

Here's the lectotype of Naos pagoda (Lang, 1926), who erected the genus based on Ptychophyllum pagoda Salter, 1873 - showing the very close dissepiment plates.

IMG_4325.thumb.jpeg.55e73439225ce85fa20f7f0ba08d870b.jpeg

Edited by TqB
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1 hour ago, TqB said:

I'm not at all sure about that, Cassandra.  It may be the same species as in the link, though I think @LisaL may be right and yours may have carinae, while that one apparently doesn't. :)  

You can't really ID corals reliably without sections though - external similarities aren't enough.  

Neither of them seems to be Naos.

 

To be Naos, it should have closely spaced dissepiment-like plates in the periphery with zig-zag septa that break up up in that region which there's no sign of there.

Also, according to the Treatise, Naos is a questionable genus anyway, only possibly present in the north American continent in the Silurian - and only listed at all from Arctic Canada, where the lectotype comes from.

Like many genera, it has probably been been applied to various things in the past that don't go with the diagnosis.

 

Here's the lectotype of Naos pagoda (Lang, 1926), who erected the genus based on Ptychophyllum pagoda Salter, 1873 - showing the very close dissepiment plates.

IMG_4325.thumb.jpeg.55e73439225ce85fa20f7f0ba08d870b.jpeg


It’d be a shame to cut it just to ID it. Plus, I don’t think she’d let me. :P Maybe when we get home tomorrow I can try some tricks to see if I can find any more details on the back. 

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1 hour ago, Cassandra Tiensivu said:


It’d be a shame to cut it just to ID it. Plus, I don’t think she’d let me. :P Maybe when we get home tomorrow I can try some tricks to see if I can find any more details on the back. 

I agree, don't cut it! Maybe wet pictures of the back would show something diagnostic (submerged rather than just wetted), or even polish a bit?

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I think Cassandra's looks close to the Hallia vesiculata Sloss in vol 11 of Stumm's Devonian Corals of the Traverse Group. Here's a closeup of Cassandra's calyx:

 

B5B526CF-B6ED-46D1-AF42-46EB8EAB7002.jpeg

 

Here's the Hallia vesiculata (Plate II, Figure 2)  from Stumm:

 

image.png.a5bf0f877baeee8a1cca5b6b6c6bcfbc.png

 

image.png.731e57566b611c45418d8700f3dc4d8f.png

 

 

Cassandra's specimen seems to show the same "pinnate development of septa in cardinal quadrants" as the Hallia in Fig 2, Plate 2 above. There are also those carinae-looking structures between the septa in Stumm's plate... (Edit: Although now, looking again, the little "bumps" between septa in the plate above may be tabulae or something? In Cassandra's, I don't see tabulae between septa.)

 

The Treatise says Hallia is found in the Middle Devonian of Ohio, (?)Ind, and Mich. (Fossilworks says it's found only from the Falls of the Ohio area in Kentucky.)

 

 

 

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2 hours ago, LisaL said:

 

I think Cassandra's looks close to the Hallia vesiculata Sloss in vol 11 of Stumm's Devonian Corals of the Traverse Group. Here's a closeup of Cassandra's calyx:

 

B5B526CF-B6ED-46D1-AF42-46EB8EAB7002.jpeg

 

Cassandra's specimen seems to show the same "pinnate development of septa in cardinal quadrants" as the Hallia in Stumm's plate (?) There are also those carinae-looking structures between the septa in Stumm's plat

 

The Treatise says Hallia is found in the Middle Devonian of Ohio, (?)Ind, and Mich. (Fossilworks says it's found only from the Falls of the Ohio area in Kentucky.)

 

 

 

It looks a good possibility. :)

 

Your plate figures don't seem to be working - not for me, anyway. Here's the Stumm plate IX, figs 1 & 2, just in case.

The septa in fig. 2 are doing some tortuous twisting and coalescing which Cassandra's certainly seems to be doing towards the centre. :)

 

1258990345_Screenshot2021-07-25at10_52_13.png.6853d08beb75dcb6fc6be312cc5c2cae.png

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Sorry about the missing photos, @TqB! I think they uploaded properly in my edit! :)

 

I was also trying to figure out how the UMMP landed on something as unfamiliar as Naos on its database. I think the cataloger must have found that genus name in Stumm's 1961 "Addenda to a Checklist of Fossil Invertebrates Described from the Traverse Group of Michigan." Stumm lists Naos ponderosa (Rominger) from the Alpena Limestone and the Gravel Point Formation (along with N. ovatus (Sloss) in the GPF. 

 

In his earlier 1951 checklist, Stumm called this genus Chonophyllum (as Rominger does in his 1876 survey of lower Michigan.) Here's Rominger's plate showing Chonophyllum:

 

chonophyllum_rominger.JPG.71eb2c0a24ad13fde5f50d4f937c73d0.JPG

 

Here's his description of the genus:

 

image.png.383b89e33f6fc9215be8b99f48a7ed04.png

image.png.1fab4f1414a82ea43a872fcf5729948e.png

 

 

All the language about invaginated cups, linear plications (he doesn't really call them septa?) and vesiculose plates in interstitial spaces are hard to wrap my head around, but the images of folding cups and vertical crests twisting in the center seems recognizable. :P 

 

Here's Rominger's description of C. ponderosa (the specimen in the plate came from Phelps Quarry in Alpena -- I think it's the same quarry we were going to visit on our fieldtrip, Cassandra!) :

 

image.png.fca398be184d9bebedcb4759618867aa.png

 

In the Treatise, Hill marks Chonophyllum as another of those questionable genera, like Naos (and which she indicates Naos might be a subjective synonym for?) The type species is from the Silurian of Gotland, Sweden and appears to be based on a specimen for which no longitudinal section is described. 

 

The Treatise presents Craterophyllum as yet another questionable genus that may be a synonym for Chonophyllum and Naos, from the upper Silurian of TN and the lower to middle Devonian of Ky-Ind-Ont.

 

Stumm describes this genus in his Silurian & Devonian Corals of the Falls of Ohio monograph, but it's not mentioned in his Traverse Group publications. Here's the plate from Falls of the Ohio:

 

craterophyllum_stumm_devsilcorals.JPG.84fcfd9c2b77ce2c7859b628fa00f2a5.JPG

 

 

Interesting that it's classified as an arachnophyllid -- the layered calices do resemble Arachnophyllum, except for its platforms of dissepiments. Are these the “transverse vesiculose plates” mentioned by Rominger? I can’t tell whether Cassandra’s has dissepiments, and there’s still the appearance of possible carinae in hers.

 

I can't figure out why Stumm mentioned Chonophyllum (then Naos) in his 1951 and 1961 checklists for the Traverse Group but does not mention either genus (or Craterophyllum) in the Devonian Corals of the Traverse Group series. The closest any of the solitary rugose corals in that series gets to Cassandra's is volume XI: Tortophyllum, Bethanyphyllum, Aulacophyllum, and Hallia. 

Here's the link if you want to compare, Cassandra! http://deepblue.lib.umich.edu/bitstream/2027.42/48354/2/ID197.pdf

 

 

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@LisaL Excellent detective work, Lisa. I think I've just about caught up! :)

 

It does seem odd that Naos/Chonophyllum ponderosa/um doesn't get a description or mention as a synonym in Stumm's Traverse papers.

It looks a good fit for the coral that @Cassandra Tiensivu has here, so I'd label it accordingly (i.e. with question marks and the suggestion that the genus needs revising.).

(I agree now that the UMP Naos ponderosa specimen was a good call, whatever it should be called. :) )

 

It might be one of the corals he didn't get round to re-describing formally - I'm sure I remember being told that that he didn't completely finish the series of papers.

 

The Hallia vesiculata calice surface in your plate also looks like the right sort of thing which shows that we need internal detail of Cassandra's and the ponderosa material to get any further. The old descriptions are hard to visualise!

(I posted the sections by mistake when your images weren't showing - yours are a better match.)

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2 hours ago, TqB said:

@LisaL Excellent detective work, Lisa. I think I've just about caught up! :)

 

It does seem odd that Naos/Chonophyllum ponderosa/um doesn't get a description or mention as a synonym in Stumm's Traverse papers.

It looks a good fit for the coral that @Cassandra Tiensivu has here, so I'd label it accordingly (i.e. with question marks and the suggestion that the genus needs revising.).

(I agree now that the UMP Naos ponderosa specimen was a good call, whatever it should be called. :) )

 

It might be one of the corals he didn't get round to re-describing formally - I'm sure I remember being told that that he didn't completely finish the series of papers.

 

The Hallia vesiculata calice surface in your plate also looks like the right sort of thing which shows that we need internal detail of Cassandra's and the ponderosa material to get any further. The old descriptions are hard to visualise!

(I posted the sections by mistake when your images weren't showing - yours are a better match.)

 

I'm about to give up. :heartylaugh: There are some interesting things going on with dissepiments in these old descriptions, though! Neither Cassandra's nor the one in the UMMP database looks like the Naos you posted earlier, with those bubbly dissepiments in the periphery. Stumm's descriptions of the genera in the (now non-extant) family Chonophyllinae seem to all mention the presence (or absence, or suppression of) dissepimental plates in zones between septa. He also weirdly describes the septa of Chonophyllum as dilated, laterally touching horizontal plates. Finally I wonder if he means the septa are flat, sort of like petals (like in this figure from his Silurian and Devonian Corals of the Falls of the Ohio). Not sure how the dissepiments fit in:

image.png.036e367f27dc1d5821450850d1620e69.png

 

And Rominger's from Plate XLIII:

 

image.png.88191063fb81f7c971ec1312549fff00.png

 

The septa appear interestingly flat, instead of long thin plates running vertically the length of the corallum.

 

Seriously, I'm making myself a little crazy now (!), so I'll quit. :headscratch:  Here's a link to Stumm's description of the old chonophyllid genera if anyone is interested! It's a Google book with limited access, so some of the genera are cut off:  https://www.google.com/books/edition/Revision_of_the_Families_and_Genera_of_t/6L9KuN4JaEMC?hl=en&gbpv=1&bsq=chonophyllum

Edited by LisaL
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@LisaL

It's bewildering, as usual with coral taxonomy. :)

 

The super-dilated septa (yes, they do look like like narrow petals) appear in various Silurian and Devonian corals which can belong to different sub-orders, so homeomorphy again. 

The dissepiments (presence or lack, naotic or not) seem to be critical to diagnosis.

 

Here's a Schlotheimophyllum patellatum from Gotland (Silurian) that shows the septa well. Cassandra's are the same sort. However, this genus is Suborder Streptelasmatina which lacks dissepiments. It used to be called Chonophyllum though! Chonophyllum has to have dissepiments.

IMG_2451.thumb.jpeg.b47d21341833fffaf9462a5dd61e0df8.jpeg

 

 

With Naos, the overall appearance is similar but it does have dissepiments, especially naotic ones (of course) near the periphery - very close accumulations that can substitute for the septa which are discontinuous.

 

So Cassandra's would perhaps have been called Chonophyllum, then Stumm decided (at least for a while, and without description) that the Alpena one was Naos. Chonophyllum (according to the Treatise) can have naotic dissepiments anyway, so that's not the difference.

 

 Here's a nice, clear 1945 take on the status of Naos, Chonophyllum and Craterophyllum by Stanley Smith, one of my favourite coral authors. (Fungites patellatus is the old name for my coral above. :) )

In Upper Devonian Corals…Canada (p.36) (partial preview only here but there are one or two very inexpensive copies available in the US!.) 

497660597_Screenshot2021-07-26at10_02_04.png.78fe6e17728b40611ded930346e3133f.png

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Cassandra Tiensivu

Ok well, it looks like I have a lot to catch up on. B) I was super tired after the long drive and ended up sleeping most of the day and through the night. Whoops!

 

But, I did try and get a macro photo of the back of the fossil, under water. I’m not sure if it helps at all, but it does appear to have a super busy pattern. 
 

 

6C9D2377-E985-4467-B1ED-7FAAF6E496BE.jpeg

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1 hour ago, Cassandra Tiensivu said:

Ok well, it looks like I have a lot to catch up on. B) I was super tired after the long drive and ended up sleeping most of the day and through the night. Whoops!

 

But, I did try and get a macro photo of the back of the fossil, under water. I’m not sure if it helps at all, but it does appear to have a super busy pattern. 
 

 

6C9D2377-E985-4467-B1ED-7FAAF6E496BE.jpeg

Oh wow, nice macro images, Cassandra! That's definitely busy structure! Could it be more evidence of the "naotic" septal structure that Tarquin has been illustrating (where the septa sort of burst open towards the edges of the calyx and flatten into dissepiment-like plates) ??

 

I just found some further images of naotic septal structure from a paper about Japanese middle-Carboniferous rugose corals. Totally unrelated to yours, but it shows the idea of how the septa break apart and flatten: 

 

 

 

image.png.577c97d5c79846db049e81450474a416.png

 

I wonder if that's the kind of structure we're seeing in the septa of yours here, along the periphery. They do look a lot like those in the Schlotheimophyllum patellatum that Tarquin posted above!

 

4A896980-7D3C-4B15-96B2-F9E6C0A24617.jpeg

 

 

EDIT: Oh snap, wait a minute. Are septa naotic or dissepiments? Schlotheimophyllum is without dissepiments; Chonophyllum is with dissepiments. So I guess that Schlotehimophyllum above (or yours) isn't showing naotic structure at all. Ugh.

Edited by LisaL
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Posted (edited)

Lisa, check this out. Those little knobby spots on the septa? They turned into bumps the further they grew out. 
 

 

 

790C6E69-1D69-43F3-BA77-367368F4FBB4.jpeg

8D4E472C-1B5F-45D8-B20C-BF7483CFDAF3.jpeg

Edited by Cassandra Tiensivu
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Those photos are incredible! I hope I'm interpreting those correctly as naic septa (I’ve been spelling it naotic)-- they seem to match with Stumm's description of one of the Craterophyllum/Chonophyllum species he describes in his Falls of the Ohio monograph. I don't know if those bumps are "rodlike vertical pillars" or what..... 

 

 

naic.JPG.cca0de9960e104c80371297ab987253e.JPG

 

I can't wait for @TqB to wake up and tell us what he sees! :) 

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@LisaL @Cassandra Tiensivu

 

Those are lovely photos, Cassandra!

 

This is a learning process but I'm becoming more convinced that we have naotic structure here.

I was trying to interpret your previous photo of the back of the coral which, due to the wear, is effectively a transverse section. Some trawling has produced this figure of naotic structure which looks spot on with same break up of the septal structure..

In the excellent   Kato, 1963, Fine Structures in Rugosa

This is plate 2, fig. 2.

 

1646738730_Screenshot2021-07-27at12_16_55.png.d656eaaaed21fd085973d12bc39ef385.png

302976988_Screenshot2021-07-27at12_13_47.thumb.jpeg.7ada40b4b256baaa436ee118dfda607c.jpeg6C9D2377-E985-4467-B1ED-7FAAF6E496BE.jpeg.ec885b06ed4c78b0ce3e8d57c9227b7e.thumb.jpeg.f2a9546d313aed37cfd7aa2070d8b244.jpeg

 

 

 

Another useful set of information and figure from the description of Pseudochonophyllum from New South Wales, showing the naotic structure of the very wide septa again.

I can imagine this might show below the surface of the bumps on Cassandra's latest photos.

 

Interestingly, Stumm was in correspondence with the author about this so he clearly knew all about naotic structure. That does rather support his ID of the Alpena material as Naos, or at least naotic.

 

In:Strusz, 1966, Spongophyllidae… Devonian… NSW  (p.563, plate 88)

 

26967476_Screenshot2021-07-27at12_04_11.png.146c82fc01b3d5f9ed49d79d25aaa136.png315150438_Screenshot2021-07-27at11_53_12.thumb.png.7e1f6a7bfd5b721cffd990ee091a35e9.png

 

 

 

Edited by TqB
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Posted (edited)

A learning curve indeed. I think I’m sitting last in the class, but I’m eagerly reading and taking notes!! 
 

So, this species would have been called Chonophyllum, but Stumm decided it was actually Naos? Was Asa likely correct with Naos ponderosum? 
 

(I think I need to open this topic up on my laptop instead of my phone. There’s so much to go through.)

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1 hour ago, Cassandra Tiensivu said:

A learning curve indeed. I think I’m sitting last in the class, but I’m eagerly reading and taking notes!! 
 

So, this species would have been called Chonophyllum, but Stumm decided it was actually Naos? Was Asa likely correct with Naos ponderosum? 
 

(I think I need to open this topic up on my laptop instead of my phone. There’s so much to go through.)

 

I believe Asa nailed it! I thought the UMMP had miscatalogued it under an invalid or old name, but from all the evidence we've found, Stumm decided on Naos for good reason! I'd love to know why he changed his mind in that 10 year period. The descriptions in the Treatise for Chonophyllum, Craterophyllum and Naos as essentially the same, except for differences in the shape of the calicular platform ("everted" in Craterophyllum; "reflexed" in Naos); and there also seem to be subtle differences in the shapes/structure of the septa (in Chonophyllum, the septa are "dilated wedgewise, thickening toward periphery," where they "may be represented by columns of naotic dissepiments" and between septa there are "narrow dissepimented. . .loculi"; both Craterophyllum and Naos are described as having long, subequal major and minor naotic septa, also with narrow interseptal spaces filled with dissepiments). The Treatise notes that a longitudinal section of the type species for Chonophyllum does not exist, so the structure of its tabulae hasn't been observed. The tabulae in Chonophyllum have been observed to be "subhorizontal, complete or incomplete" and in Naos they are "subhorizontal, commonly incomplete."

Maybe the lack of the longitudinal section for the type specimen of Chonophyllum is partly what caused Stumm to later change his mind and go with Naos?

 

At any rate, I think it makes sense to ID yours as ?Naos ponderosum after Stumm's example, even though we can't see those dissepimented loculi or the tabulae. Would you say so, too, @TqB? (Maybe with a question mark in front to show there's some uncertainty about the genus?)

 

Those bumps that I thought were carinae turned out to be naotic structure in the septa!

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I'm fascinated by the idea that these corals seem to build themselves up on platforms of flattened, burst open septa. (My mind was similarly blown to realize that Arachnophyllum held itself together with septa laid on top of platforms of horizontal dissepiments, one after another.)  Looking again at Stanley Smith's description of Naos that Tarquin provided above, the "open" septa at the periphery seem to mark a mature stage in the coral's growth. Wonder what makes them burst open as they mature?

 

Questions never end!

 

I really love this discussion, Cassandra and Tarquin. Thanks to you both!

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I agree, Naos ponderosus (Rominger) (see below for the -us ending) looks a very good ID, pending any revision of the genera involved. Perhaps put Chonophyllum in brackets, mainly to allow referencing to Rominger?

(I think that attribution to Naos in a checklist counts as a published emendation (not sure though), but a formal revision with reasoning would of course be better. But then we wouldn't have had the fun of working it out. :) )

 

It was Cassandra's detailed photos that made Naos make sense, reinforced especially by the view of the worn base. Zooming in on the specimen on the UMMP database, you can make out similar bumpy surface structure.

 

[-us is probably the proper ending for the species. As far as I can find out, "naos" is masculine and adjectival species names have to agree.

For Lang's type species N. pagoda, "pagoda" is a noun so doesn't change its ending when used as a species.

Nponderosus is used in piranha's link (3rd comment) on the Alpena strata, which the author derives from Stumm's checklist mentioned by Lisa.]

 

@LisaL Maybe the apparent carinae are the more normal dissepiments that you get towards the centre? I'm not at all sure though- it's hard to tell without chopping it!

 

It's been a very enjoyable discussion, thanks Cassandra, and to Lisa for digging out the essential old references. :)  

 

 

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Tidgy's Dad

Excellent thread.

A super example of Forum teamwork producing a result. :i_am_so_happy:

Thanks, all. 

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