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Missourian

Mystery Fossils (Pennsylvanian)

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Herb

:wub::popcorn:

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Missourian

For comparison, here are some conceptacle-bearing blades of Archaeolithophyllum (found by Kehbe):

 

post-6808-0-56520600-1384158876_thumb.jpg

 

They can be seen as 'serrations' on a couple blades, which are ~1 mm in thickness. These algae are preserved in the more usual manner in the Pennsylvanian Raytown Limestone of KC.

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Missourian

Variation in branching:

 

post-6808-0-57384700-1391210794_thumb.jpg

 

I wonder if the style of branching is a response to local variations in environmental conditions, such as turbulance/currents and sedimentation?

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Missourian

I may be a step or two closer to solving the mystery.

 

1) Kansas Geological Survey Bulletin 198 ("Algal-Bank Complex in Wyandotte Limestone (Late Pennsylvanian) In Eastern Kansas", at: http://www.kgs.ku.edu/Publications/Bulletins/198/index.html ) has the following illustration of the alga Anchicodium:

 

post-6808-0-57230500-1392954232_thumb.jpg

 

The caption given is:

 

"D, Phylloid algal pelmicrite. Large blades of Anchicodium (An) lying concave-upward and filled with pelmicrite. Limonitic, silty micrite beneath blades contains possible calcite pseudomorphs after anhydrite or celestite (arrow), some with hexagonal cross sections. Spar (S) fills primary voids beneath higher parts of blades. Locality 1 (3)."

 

This is very similar to thalli preserve in concretions (pockets of early, pre-compaction cementation) at my location:

 

post-6808-0-67799500-1392954233_thumb.jpg

 

With void beneath the thallus, but no calcite spar (just left of center):

 

post-6808-0-30156200-1392954230_thumb.jpg

 

2) The paper "Senowbari-Daryan, Baba; Rashidi, Koorosh, 2010: The codiacean genera Anchicodium Johnson, 1946 and Iranicodium nov gen from the Permian Jamal Formation of Shotori Mountains, northeast Iran. Rivista Italiana di Paleontologia e Stratigrafia 116.1" states that the thallus morphology of Anchicodium is similar to that of tape. An excerpt of the abstract:

 

"Definition of the codiacean genus Anchicodium Johnson (Algae, Chlorophyta) is revised. Anchicodium is morphologically straight, curved, undulating or even irregular tapes and not cylindrical as defined by previous authors."

 

The paper does not actually illustrate a tape-like thallus. It infers such a form from thalli observed in thin section.

 

A problem is that there seems to be absolutely no illustrations of the morphology of Anchicodium anywhere. That includes specimens and reconstructions. I'm wondering if I'm holding the only known examples....

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Tethys

I may have solved this mystery. Your algae looks very much like the Calcipatera community illustrated in photo i of this paper. It also details the other organisms found in association with the thalli.

http://www.kgs.ku.edu/Current/2005/sawin/06_comm.html

"Specimens of the brachiopod Crurithyris, in presumed life position, occur on the exterior of some thalli (fig. 7a). Whole (articulated and disarticulated) and fragmented shells of Crurithyris also occur in the cup-filling sediment. Minammodytes?, an encrusting foraminifer, occurs attached to the exterior of some thalli (fig. 7b). Another encrusting foraminifer, Tuberitina, is attached to the interior (fig. 7c), and also contributes to the skeletal fraction of the cup-filling sediment. Crurithyris and the encrusting foraminferids occur near the upper edges of the algal thalli. A fenestrate bryozoan, attached to the exterior, is nearly encased by an algal thallus (fig. 7d).Shamovella is found within the substrate as well as attached to the thalli. Mobile benthic textulariine foraminifers (fig. 7e) and gastropods (fig. 7f) also are associated with the community. Additionally, fragments of pseudopunctate brachiopod shells, bivalve shells, ostracodes, trilobites, and echinoids were observed on polished surfaces and in thin sections. These taxa do not appear to have contributed significantly to the fabric of the bafflestone. These associated organisms were either epiphytic on the phylloid algae or capable of surviving in the cryptic niches beneath or within the Calcipatera clusters."

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Missourian
On 2/26/2014 at 10:35 AM, Tethys said:

I may have solved this mystery. Your algae looks very much like the Calcipatera community illustrated in photo i of this paper. It also details the other organisms found in association with the thalli.

http://www.kgs.ku.edu/Current/2005/sawin/06_comm.html

 

Thanks. Yes, I've seen this paper. Some of the thalli I've found resemble the cup-like forms of Calcipatera, particularly Fig. 6 (i) and (j):

 

post-6808-0-19490100-1393455494_thumb.jpg

 

(j) comes closest of anything in the literature that resembles the branching, segmented forms. It's a shame that the illustrations in the paper are of such poor quality.

 

(i) resembles some the flat to cup-shaped thalli. A couple examples (both on the same slab):

 

Flattened 'cup'?:

 

post-6808-0-12572400-1393456361_thumb.jpg

 

Unflattened cross-section of 'cup':

 

post-6808-0-14063800-1393456364_thumb.jpg

 

There seems to be a continuum in form variation. The thalli range from smooth & sheet-like, to lobed & rippled, to branching & segmented. I still believe at least two species are represented, if not more.

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Missourian

FWIW, here are some reconstructions of various Pennsylvanian and Permian calcareous algae....

 

Archaeolithophyllum (Rhodophyta - red alga):

 

post-6808-0-16415600-1393458375_thumb.gif

 

From Archaeolithophyllum, an Abundant Calcareous Alga in Limestones of the Lansing Group (Pennsylvanian), Southeastern Kansas, Kansas Geological Survey Bulletin 170, at http://www.kgs.ku.edu/Publications/Bulletins/170_1/ ).

 

A few specimens found in the Raytown Limestone at Kansas City indicate cup-shaped thalli:

 

post-6808-0-51496000-1393458866_thumb.jpg

 

Eugonophyllum (Chlorophyta - green alga):

 

post-6808-0-44730400-1393458909_thumb.jpg

 

From Reconstruction of a Cyathiform Eugonophyllum, Upper Pennsylvanian, Palo Pinto County, Texas, Torres, A. M., Journal of Paleontology, 1997.

 

Ivanovia (Chlorophyta - green alga):

 

post-6808-0-67010300-1393459125_thumb.jpg

 

From Ivanovia tebagaensis Was a Cyathiform Permian Codiacean Membranous Alga with Dimorphic Cortices, Torres, A. M., Journal of Paleontology, 1995.

 

Calcipatera (Chlorophyta - green alga):

 

post-6808-0-22540900-1393459278_thumb.jpg

 

Reconstructions from Calcipatera cottonwoodensis, a New Membraneous Late Paleozoic Calcareous Alga, Torres, A. M., West, R. R., and Sawin, R. S., Journal of Paleontology, 1992.

 

These calcareous algae found in a limestone in Kansas City Missouri (Westerville Ls.?) seems to have a similar frilly thallus edge like Calcipatera:

 

post-6808-0-97722400-1393459491_thumb.jpg

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Tethys

The link is several pages long, I just linked to the page with the photos. On the introduction page it discusses the different growth forms that have been documented.

"Two growth habits have been recognized for Archaeolithophyllum: an encrusting form, A. lamellosum (Wray, 1964; Wahlman, 1988, 2002) and an erect "phylloid" form for A. missouriense (Wahlman 1985, 1988, and 2002). The growth habit of Calcifolium has been inferred, but in situ evidence is undocumented in the literature."

and this description

"As described by Laporte (1962, p. 531), the thin, wavy, plate-like thalli are generally oriented parallel to bedding, and in weathered relief, give the rock an irregular, crenulated texture--a texture often described as a pile of potato-chips or corn-flakes. At this exposure, the algal packstone is referred to as an accumulational occurrence, and the in situ unit is referred to as a constructional occurrence"

It took a few readings, but my take is that there are two growth forms which may or may not be the same species.

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Missourian
On 2/26/2014 at 10:35 AM, Tethys said:

"Specimens of the brachiopod Crurithyris, in presumed life position, occur on the exterior of some thalli (fig. 7a). Whole (articulated and disarticulated) and fragmented shells of Crurithyris also occur in the cup-filling sediment.

 

The brachiopods attached to the thalli are similar to Crurithyris in form, but they are a bit smaller and have short spines. Other fossils directly associated with the thalli are a few other small brachs (Kozlowskia?, et al.), encrusting bryozoans (Fistulipora), fenestrate bryozoans, sponges (mainly Coelocladia), and burrow traces. The Crurithyris-like brachs seem to be the most common. The other fossils are rather sparse.

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Missourian
On 2/26/2014 at 7:12 PM, Tethys said:

On the introduction page it discusses the different growth forms that have been documented.

"Two growth habits have been recognized for Archaeolithophyllum: an encrusting form, A. lamellosum (Wray, 1964; Wahlman, 1988, 2002) and an erect "phylloid" form for A. missouriense (Wahlman 1985, 1988, and 2002). The growth habit of Calcifolium has been inferred, but in situ evidence is undocumented in the literature."

and this description

"As described by Laporte (1962, p. 531), the thin, wavy, plate-like thalli are generally oriented parallel to bedding, and in weathered relief, give the rock an irregular, crenulated texture--a texture often described as a pile of potato-chips or corn-flakes. At this exposure, the algal packstone is referred to as an accumulational occurrence, and the in situ unit is referred to as a constructional occurrence"

It took a few readings, but my take is that there are two growth forms which may or may not be the same species.

 

I've seen descriptions like "tape-like" and "crenulated texture" in the literature that may indicate the segmented forms, but there's no way to tell for sure unless someone does a painstaking reconstruction of thalli locked away in limestone -- or happens to find specimens weathering out of shale, which is almost entirely unheard of.

 

The proper way to identify my fossils as Archaeolithophyllum or Calcipatera (or whatever) would be to examine the structure of thalli in cross-section under the microscope. Unfortunately, the thalli appear to be completely recrystalized and may no longer display any internal structure.

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Tethys

Doesn't everybody wish they had a SEM at their disposal?

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Missourian
On 2/26/2014 at 7:53 PM, Tethys said:

Doesn't everybody wish they had a SEM at their disposal?

 

I certainly would, but then I wouldn't get much else done. :)

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Missourian
On 2/26/2014 at 7:41 PM, Missourian said:

The proper way to identify my fossils as Archaeolithophyllum or Calcipatera (or whatever) would be to examine the structure of thalli in cross-section under the microscope. Unfortunately, the thalli appear to be completely recrystalized and may no longer display any internal structure.

 

For reference, a comparison between cross-sections of red phylloid algae (Archaeolithophyllum lamellosum) on the left and green phylloid algae (Anchicodium iranicum) on the right:

 

post-6808-0-48258100-1393580131_thumb.jpg

 

These specimens are exceptionally well preserved. Lesser-quality examples would lack finer details but show a sandwich-like layering in both cases, which would make it hard to distinguish between the two. Typically, though, all that is left is featureless, sparry calcite.

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Tethys

Speaking of not getting anything done, you might be interested in

Atlas Of Microbial Mat Features Preserved Within The Siliclastic Rock Record

I have not read all of it yet, but it has many excellent photographs of the different growth forms and preservation structures that occur depending on substrate, and deposition environment.

I'm currently admiring the quartz arenite sandstone fossil trackways in WI, but there is a large chapter devoted to muddy environments.

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Missourian

These Pennsylvanian thalli can be compared to modern calcareous algae. It's unlikely that they are closely related, but the growth forms may be quite similar.

 

The form of some modern coralline algae resemble many of the smoother thalli.

 

Mesophyllum lichenoides

Rhodophyta (red algae)

 

post-6808-0-99441800-1393617132_thumb.jpg

 

These are similar in general form:

 

post-6808-0-56711400-1393617125_thumb.jpg

 

Lithophyllum stictaeforme

Rhodophyta

 

post-6808-0-45264500-1393617399_thumb.jpg

 

Archaeolithophyllum was compared with this when it was first described. Note the attached critter peeking out in the lower left.

 

Peyssonnelia squamarina

Rhodophyta

 

post-6808-0-12951200-1393617135_thumb.jpg

 

Another similar coralline.

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Missourian

Some modern red algae can be compared to the branching, segmented thalli.

 

Galaxaura marginata

Rhodophyta

 

post-6808-0-08711700-1393616361_thumb.jpg

 

The ribbon-like form and dichotomous branching of these lightly calcified algae closely resemble the segmented thalli:

 

post-6808-0-74993700-1393616641_thumb.jpg

 

Mastophora rosea

Rhodophyta

 

post-6808-0-14761900-1393616970_thumb.jpg

 

This alga is somewhat similar in appearance, but the branching is a little irregular. Note the attached epifauna.

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Missourian

Padina antillarum

Phaeophyta (brown algae)

 

post-6808-0-50828100-1393617695_thumb.jpg

 

The banding and (irregular) branching of the lightly-calcified Padina also has a resemblance to some of the branching thalli. Brown algae are extremely rare in the fossil record, so it's unlikely that these belong to that group. I would certainly be quite happy if they turned out to be an exception.

 

There are some modern green algae that have similarities.

 

Udotea cyathiformis

Chlorophyta (green algae)

 

post-6808-0-18144900-1393617697_thumb.jpg

 

These could be similar to some cup- to spoon-shaped thalli:

 

post-6808-0-52591300-1393617693_thumb.jpg

 

Udotea flabellum

Chlorophyta

 

post-6808-0-23072000-1393617699_thumb.jpg

 

This is more like the flatter, lobed thalli.

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Missourian

I finally made it back to the site to collect some more specimens. I also snapped some photos of the strata. The 'pahoeid' zone is near the top of the gray shale:

 

post-6808-0-50139400-1395014854_thumb.jpg

 

Unfortunately, the thin beds and lenses of limestone containing 'pahoeids' are not often exposed at the surface. Here is one instance:

 

post-6808-0-57903100-1395013220_thumb.jpg

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Missourian

In one spot, I found some 'pahoeids' at the top of the slope here:

 

post-6808-0-71883000-1395013436_thumb.jpg

 

One piece displayed some nice detail:

 

post-6808-0-75615400-1395013480_thumb.jpg

 

So I dug back into the shale a bit to see if I could get some more:

 

post-6808-0-19803000-1395013536_thumb.jpg

 

post-6808-0-86928700-1395013540_thumb.jpg

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Missourian

Pretty quickly, I found this beauty:

 

post-6808-0-57235000-1395013616_thumb.jpg

 

A portion of the thallus was loose:

 

post-6808-0-61761100-1395013625_thumb.jpg

 

beneath the detached portion is a second thallus (or group of thalli):

 

post-6808-0-83881900-1395013621_thumb.jpg

 

Interestingly, there are a couple crinoid fragments between the thalli. This may provide some information on the growth rate and habit of these organisms, as well as the paleoecology, taphonomy and sedimentation of the immediate area. Also, as previously suspected, I was able to confirm that these thalli are exposed on the bottom side of the beds.

 

I found many fragments at the spot. I've yet to clean them off, so I don't know how well preserved they are, or if they will combine together into a larger piece.

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Auspex

I doff my hard had to you; this topic is amazing!

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Wrangellian

Thanks for showing us how you collect these. Can't wait to see if your pieces come together.

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Missourian
On 3/16/2014 at 7:03 PM, Auspex said:

I doff my hard had to you; this topic is amazing!

 

Thanks. I'd have to agree. :)

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Missourian
On 3/17/2014 at 4:02 AM, Wrangellian said:

Thanks for showing us how you collect these. Can't wait to see if your pieces come together.

 

It may be a while. The caked-on mud will take a little time to clean off (mainly due to my laziness :) ), and because of Murphy's Law, I'm sure there are a few pieces of the puzzle that remain in the muddy hole.

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