Showing posts with label russian. Show all posts
Showing posts with label russian. Show all posts

Tuesday, April 16, 2024

BACK IN THE USSR: BEADANTICERAS OF THE NORTHERN CAUCASUS

This lovely oil in water coloured ammonite is the beauty Beudanticeras sp. from the Lower Cretaceous (Upper Aptian), Krasnodar region, Northern Caucasus, southern Russia. 

This area of the world has beautiful fossil specimens with their distinct colouring. The geology and paleontological history of the region are fascinating as is its more recent history. 

The territory of present Krasnodar Krai was inhabited as early as the Paleolithic, about 2 million years ago. It was inhabited by various tribes and peoples since ancient times. There were several Greek colonies on the Black Sea coast, which later became part of the Kingdom of the Bosporus. In 631, the Great Bulgaria state was founded in the Kuban. In the 8th-10th centuries, the territory was part of Khazaria.

In 965, the Kievan Prince Svyatoslav defeated the Khazar Khanate and this region came under the power of Kievan Rus, Tmutarakan principality was formed. At the end of the 11th century, in connection with the strengthening of the Polovtsy and claims of Byzantium, Tmutarakan principality came under the authority of the Byzantine emperors (until 1204).

In 1243-1438, this land was part of the Golden Horde. After its collapse, Kuban was divided between the Crimean Khanate, Circassia, and the Ottoman Empire, which dominated in the region. Russia began to challenge the protectorate over the territory during the Russian-Turkish wars.

In 1783, by decree of Catherine II, the right-bank Kuban and Taman Peninsula became part of the Russian Empire after the liquidation of the Crimean Khanate. In 1792-1793, Zaporozhye (Black Sea) Cossacks resettled here to protect new borders of the country along the Kuban River. 

During the military campaign to establish control over the North Caucasus (Caucasian War of 1763-1864), in the 1830s, the Ottoman Empire for forced out of the region and Russia gained access to the Black Sea coast.

Prior to the revolutionary events of 1917, most of the territory of present Krasnodar Krai was occupied by the Kuban region, founded in 1860. In 1900, the population of the region was about 2 million people. In 1913, it ranked 2nd by the gross harvest of grain, 1st place for the production of bread in the Russian Empire.

The Kuban was one of the centres of resistance after the Bolshevik revolution of 1917. In 1918-1920, there was a non-Bolshevik Kuban People’s Republic. In 1924, North-Caucasian krai was founded with the centre in Rostov-on-Don. In 1934, it was divided into Azov-Black Sea krai (Rostov-on-Don) and North Caucasus krai (Stavropol).

September 13, 1937, the Azov-Black Sea region was divided into the Rostov region and Krasnodar Krai that included Adygei autonomous oblast. During the Second World War, the region was captured by the Germans. After the battle for the Caucasus, it was liberated. There are about 1,500 monuments and memorials commemorating heroes of the war on the territory of Krasnodar Krai.

The lovely block you see here is in the collections of the awesome John Fam, Vice-Chair of the Vancouver Paleontological Society in British Columbia, Canada.

Monday, January 22, 2024

QUENSTEDTOCERAS WITH PATHOLOGY

What you are seeing here is a protuberance extruding from the venter of Quenstedtoceras cf. leachi (Sowerby). It is a pathology in the shell from hosting immature bivalves that shared the seas with these Middle Jurassic, Upper Callovian, Lamberti zone fauna from the Volga River basin. The collecting site is the now inactive Dubki commercial clay quarry and brickyard near Saratov, Russia. 

The site has produced thousands of ammonite specimens. A good 1,100 of those ended up at the Black Hills Institute of Geological Research in Hill City, South Dakota. 

Roughly 1,000 of those are Quenstedtoceras (Lamberticeras) lamberti and the other 100 are a mix of other species found in the same zone. These included Eboraciceras, Peltoceras, Kosmoceras, Grossouvria, Proriceras, Cadoceras and Rursiceras

What is especially interesting is the volume of specimens — 167 Quenstedtoceras (Lamberticeras) lamberti and 89 other species in the Black Hills collection — with healed predation injuries. It seems Quenstedtoceras (Lamberticeras) lamberti are the most common specimens found here and so not surprisingly the most common species found injured. Of the 1,000, 655 of the Quenstedtoceras (Lamberticeras) lamberti displayed some sort of deformation or growth on the shell or had grown in a tilted manner. 

Again, some of the Q. lamberti had small depressions in the centre likely due to a healed bite and hosting infestations of the immature bivalve Placunopsis and some Ostrea

The bivalves thrived on their accommodating hosts and the ammonites carried on, growing their shells right up and over their bivalve guests. This relationship led to some weird and deformities of their shells. They grow in, around, up and over nearly every surface of the shell and seem to have lived out their lives there. It must have gotten a bit unworkable for the ammonites, their shells becoming warped and unevenly weighted. Over time, both the flourishing bivalves and the ammonite shells growing up and over them produced some of the most interesting pathology specimens I have ever seen.    

In the photo here from Emil Black, you can see some of the distorted shapes of Quenstedtoceras sp. Look closely and you see a trochospiral or flattened appearance on one side while they are rounded on the other. 

All of these beauties hail from the Dubki Quarry near Saratov, Russia. The ammonites were collected in marl or clay used in brick making. The clay particles suggest a calm, deep marine environment. One of the lovely features of the preservation here is the amount of pyrite filling and replacement. It looks like these ammonites were buried in an oxygen-deficient environment. 

The ammonites were likely living higher in the water column, well above the oxygen-poor bottom. An isotopic study would be interesting to prove this hypothesis. There's certainly enough of these ammonites that have been recovered to make that possible. It's estimated that over a thousand specimens have been recovered from the site but that number is likely much higher. But these are not complete specimens. We mostly find the phragmocones and partial body chambers. Given the numbers, this may be a site documenting a mass spawning death over several years or generations.

If you fancy a read on all things cephie, consider picking up a copy of Cephalopods Present and Past: New Insights and Fresh Perspectives edited by Neil Landman and Richard Davis. Figure 16.2 is from page 348 of that publication and shows the hosting predation quite well. 

Photos: Courtesy of the deeply awesome Emil Black. These are in his personal collection that I hope to see in person one day. 

It was his sharing of the top photo and the strange anomaly that had me explore more about the fossils from Dubki and the weird and wonderful hosting relationship between ammonites and bivalves. Thank you, my friend!

Tuesday, August 23, 2022

ELASMOTHERIUM: THE STEPPE RHINOCEROS

Elasmotherium was a prehistoric cousin of the rhinoceros. These animal lived in Europe and Asia during the Pleistocene. They have a wonderfully impressive large horn that makes them easy to identify.

Elasmotherium means, "Thin Plate Beast." They are sometimes called the Steppe Rhinoceros. 

By any name they are an extinct genus of giant rhinoceros endemic to Eurasia during the Late Pliocene through the Pleistocene, documented from 2.6 million years ago, to as late as 50,000 years ago, possibly later, in the Late Pleistocene, an approximate span of slightly less than 2.6 million years. 

Three species are recognized. The best known, E. sibiricum was about the size of a mammoth and is thought to have borne a large, thick horn on its forehead which was used for defense, attracting mates, driving away competitors, sweeping snow from the grass in winter and digging for water and plant roots. 

Like all rhinoceroses, elasmotheres were herbivorous. Unlike any others, its high-crowned molars were ever-growing. Its legs were longer than those of other rhinos and were designed for galloping, giving it a horse-like gait. The Russian paleontologists of the 19th century who discovered and named the initial fossils were influenced by ancient legends of a huge unicorn roaming the steppes of Siberia. To date no evidence either contradicts or confirms the possibility that Elasmotherium survived into legendary times.

Thursday, November 11, 2021

CADOCHAMOUSSETIA SUBPATRUUS

Cadochamoussetia subpatruus (Nikitin 1885)
I have a thing for chunky ammonites and find their inflated shapes very pleasing. 

This lovely chunky macroconch is the female of the species Cadochamoussetia subpatruus (Nikitin 1885). 

She hails from the Middle Jurassic, Lower Callovian, Elatmae zone, Subpatruus subzone in a clay mining quarry near Uzhovka 2, in the Pochinoksky district of Nizhny of the Novgorod region of western Russia. 

This specimen has signs of intravital damage (i.e., damage that did not immediately lead to death) on the edge of her shell. 

We see this type of non-lethal damage recorded on the shells of ammonites and other marine goodies in the fossil record. These telltale bits of evidence for challenges to the species while living are recorded and preserved long before the burial event. We see similar signs of damage on the shells of modern Nautilus. 

These lesions resemble frequently bitten edges. Perhaps damage from predation or the result of bashing up against something solid on the seafloor. There is a wee bit more damage on the mouth of the shell. Where the shell should have stopped growing upon the ammonite reaching puberty, the growth continues for another 5 cm of thinly laminated shell — perhaps signalling physicochemical impact or shortage of resources for the ongoing construction of the usual thickness. This photo is courtesy of the deeply awesome Emil Black.