Oviposition-Scars On A Calamite Stem From The Westphalian D Of The Piesberg, Germany

[paleoflor]

Dear all,

It was difficult, very difficult to wait with posting, since I am very, very excited about this fossil find. However, I also wanted the Dutch magazine version to come out first. Well, it finally did this Tuesday, so here is some info in English, along with a couple of the figures.

During a visit to the Piesberg near Osnabrück (Germany) in 2010, I found a stem fragment of Calamites decorated with strange, elongate-oval structures [Fig. 1]. While those features were unusual and quite remarkable, it proved difficult to find information about them and the fossil consequently went into my collection as unidentified. Last January, however, I stumbled upon a research paper that could shed light on the matter. The elongate-oval structures turn out to be one of the oldest-known examples of endophytic oviposition, i.e. egg-laying inside plant tissue, by insects.

Fig. 1.

The fossil specimen is atypical in several respects [Fig. 2]. The stem fragment doesn’t show the longitudinal ribs one usually sees on the internodes of Calamites. This is because we are looking at a preservation of the epidermis (outer layer of the stem), not at a cast of the central pith, which are more commonly found. Fossils of the epidermis (sometimes referred to as Calamophyllites) typically have internodes with a smooth surface (though it may be lightly striated or wrinkled), leaving few diagnostic features. Nonetheless, due to the presence of a characteristic nodal line with large, circular branch-scars [Fig. 2, shown on schematic in green], the fossil fragment can be identified as Calamites (subgenus Calamitina) with reasonable confidence.

Below the nodal line with branch-scars, about eight elongate-oval structures can be observed [Fig. 1]. They are all orientated roughly parallel to the axis of the calamite stem and vary in length from 6 to 16 mm. A foreign nature with respect to the plant tissue is suggested by the gümbelite film in which the epidermis is preserved (gümbelite is a hydromuscovite and responsible for the well-known silver-grey colour of the fossils from the Piesberg). Note how this thin film of mineralization does not extend across several of the elongate-oval structures, which may indicate that the plant tissue there is either missing or damaged. Their exact origin, however, remained a mystery to me. Until recently.

Fig. 2.

While looking for information on some Carboniferous localities in France, I happened upon the research article ‘Earliest Evidence of Insect Endophytic Oviposition’ by Olivier Béthoux et al. (2004). The paper describes insect egg-laying structures, called oviposition-scars, found on two stem fragments of Calamites cistii from the Upper Carboniferous (Stephanian B/C) of Graissessac, Southern France. These scars are elongate-oval structures, orientated parallel to the axis of the stem, occurring on a preservation of calamite epidermis [see their Figures 1 and 2]. Careful preparation of three of these scars yielded small spherical cavities, which the researchers interpreted as imprints of the eggs themselves [see their Figure 2b]. The oviposition-scars from Graissessac vary in length from 5 to 38 mm and are surrounded by a thin film of organic material [see their Figure 2c]. Given the strong resemblance with the Piesberg-material, it didn’t take long to make the link with the mystery markings I found years earlier.

Now, after confirmation by email from Olivier Béthoux and in person from Han van Konijnenburg-van Cittert, I can with reasonable certainty say that some sort of Carboniferous insect has laid its eggs in the calamite stem I found in the Piesberg quarry. This type of trace fossils is quite rare, so I am very happy I brought this one home. As a nice bonus this specimen comes from the Westphalian D, and is thus somewhat older (about 4 million years) than the published material from Graissessac (Stephanian BC), which is still cited as the oldest occurrence in recent literature. So you can really say this specimen from the Piesberg is one of the oldest examples around!

Hope this was as fun and informative as this fossil has been for me,

Tim

Edited July 17, 2014 by paleoflor

[Fossildude19]

Amazing, Tim!

Congratulations on this find.

Thanks for posting it.

Regards,

[Auspex]

I am stunned and amazed! And excited for you! And...practically speechless!

In light of your preceding body of work, and scholarship thereof, this is a crowning glory.

This deserves The Fossil Forum's Golden Drool Bucket Award, bestowed herewith!

[Mattalic]

AMAZING!

[paleoflor]

This deserves The Fossil Forum's Golden Drool Bucket Award, bestowed herewith!

Given the previous awardees, it is a real honor to have my specimen ranked among the GDB fossils/collections. Many thanks.

@ Tim (Fossildude19) and Mattalic: Thanks for the nice comments.

[Missourian]

Most fascinating.

It's amazing that signs of insect life are not more common in the Pennsylvanian. Those bugs certainly make their presence known in the garden.

[Rockaholic]

Great discovery! It’s a lesson in looking for subtle detail when examining fossil specimens.

[paleoflor]

Most fascinating.

It's amazing that signs of insect life are not more common in the Pennsylvanian. Those bugs certainly make their presence known in the garden.

Most trace fossils of insect-plant interaction involve traces of eating. Those are (relatively) common, see link below.

Great discovery! It’s a lesson in looking for subtle detail when examining fossil specimens.

Indeed! For me it was an eye-opener which spurred me to do a bit more reading on the fossil traces of insect-plant interaction. While looking for information, I came across the "Insect Damage Guide" by Conrad Labandeira. It provides some nice examples that help recognize this kind of beautiful fossils in the field.

[piranha]

Congrats on the GDB award for all of your excellent and informative research!

[Xiphactinus]

Awesome find, and congrats on the GDB!

[Missourian]

Most trace fossils of insect-plant interaction involve traces of eating. Those are (relatively) common, see link below.

Well then that would explain all the incomplete leaves in my collection.

Edited July 22, 2014 by Missourian

[rew]

Very cool. Congratulations on your find.

[Plantguy]

I am stunned and amazed! And excited for you! And...practically speechless!

In light of your preceding body of work, and scholarship thereof, this is a crowning glory.

This deserves The Fossil Forum's Golden Drool Bucket Award, bestowed herewith!

Golden Drool Bucket.jpg

Hey Chas, I know I've seen these super fossil awards and they are always real stunners......Is there a single thread/repository or way to see them all...Is it in the members sections somewhere? Regards, Chris

[Plantguy]

Given the previous awardees, it is a real honor to have my specimen ranked among the GDB fossils/collections. Many thanks.

@ Tim (Fossildude19) and Mattalic: Thanks for the nice comments.

Hey Tim, this is a really fantastic plant/insect fossil find! I'm quite sorry that I missed the post it in my sporadic visits to the site...so glad this got bumped again! Neat to see how you were able to arrive at the ID.

So, I'm not clear and it could be that we just got back from the Brooksville quarry on an echy field trip and I'm baked and overheated but what are the next steps f any...is further study of the fossil planned/review/publication in the works?

Quite a find! Congrats! Regards, Chris

[paleoflor]

Whoa, I should've kept more of an eye on this topic. Sorry for the sloppy responsiveness.

@ All: thanks for the congratulations. Getting the GDB award for this specimen is an honor.

@ Chris: Before I wrote something on it, I sent images of the fossil to several palaeo-entomologists asking whether they would be interested in studying it further. While they could confirm the ID, nobody showed interest in studying the specimen in more detail. Actually, it is this lack of interest that spurred me to write a little something on the fossil myself, for it was a new occurrence of this type of trace-fossil, and the oldest occurrence known at that. Anyway, the only manuscript dealing with the specimen is a short, non peer-reviewed publication by the Dutch Geological Society, in Dutch. About half of that article I translated into English above.

Tim

[fossilized6s]

Thanks for the informative write up Tim. I'll have to keep a sharp eye when finding my Calamites from Mazon.

Congrats on the awesome find and award for a long and hard detective work! Your knowledge on fossil flora is priceless on here. Thank you!

[Shamalama]

Amazing find and even more amazing that you found research to explain it! Congrats on the GDB, you deserve it!

[docdutronc]

Hi Tim

Look here ,these enigmatic shapes could be oviposition cavity on a fern rachis ( Aulacopteris ) . They are counterparts in compression impression . Pictures collection of my friend Hervé ,Liévin Basin ( France ) ,Bolsovian .

Best regards

Bruno

Edited April 24, 2015 by docdutronc

[paleoflor]

Hi Bruno,

Interesting specimens! Not sure whether these could be oviposition scars, but if they are, they are simply enormous! Perhaps it is worth sending your photographs to Conrad Labandeira to ask for his expert opinion?

In the meantime, I have been able to find photographs of additional specimens in the literature (though not identified as such). Will need time to digitize these though...

Cheers,

Tim

[paleoflor]

Hi Bruno,

The image below might be of interest to you. I vaguely remembered seeing something similar in one of my books, and I have located that photo. Below a photograph of Plate 133-2 of Kidston and Jongmans (1915). The oval markings on this specimen look rather similar to your structures... but then on a Calamites stem. Unfortunately, Kidston and Jongmans do not address these structures at all in their text-volume.

Have a nice w/e,

Tim

[paleoflor]

Calamites specimen from Poland with apparent oviposition-scars?

[docdutronc]

Hi Bruno,

The image below might be of interest to you. I vaguely remembered seeing something similar in one of my books, and I have located that photo. Below a photograph of Plate 133-2 of Kidston and Jongmans (1915). The oval markings on this specimen look rather similar to your structures... but then on a Calamites stem. Unfortunately, Kidston and Jongmans do not address these structures at all in their text-volume.

Have a nice w/e,

Tim

P1060442.JPG

Hi Tim

very curious these ovals markings !!!!

These vertical scars on this Lepidodendron bark attracted my attention, what do you think about these vertical marks?

Bruno

Edited May 10, 2015 by docdutronc

[paleoflor]

Intriguing! Do you know what they are?

[docdutronc]

Bonsoir

No , I don't know , probably not parichnos or not leaf beams !!!!

Bruno

[paleoflor]

My apologies for reviving this long-dead thread, but recently an interesting paper was published on the earliest record of exophytic oviposition (as opposed to endophytic) from the Gzhelian of Germany by Laass and Hauschke (2019). Beautiful trace fossils and ditto interpretation. The paper also provides a rather nice overview of the Palaeozoic fossil record of oviposition scars, including a reference to the Piesberg-specimen discussed in this thread, which is now officially listed as the oldest to date! Not sure whether everyone will be able to directly access the full-text PDF, but if not consider obtaining the paper from the authors via ResearchGate.