Wooster’s Fossil of the Week: A twisted scleractinian coral from the Middle Jurassic of southern Israel
Mark Wilson April 24th, 2015
Another exquisite little coral this week from the collection of Matmor Formation (Middle Jurassic, southern Israel) corals Annette Hilton (’17) and I are working through. We believe this is Epistreptophyllum Milaschewitsch, 1876. It is a solitary (although more on that in a moment) scleractinian coral found in marly sediments at our location C/W-366 in Hamakhtesh Hagadol. I’m always impressed at how well preserved these corals are considering their original aragonitic skeletons were replaced long ago.
One cool thing about this specimen is the near 90° bend it took during growth. Apparently it was toppled over midway through its development but survived and grew a twist so it could keep its oral surface (where the polyp resided) upwards. Another interesting observation is the small bud visible near the base. Gill (1982) suggested that the solitary Epistreptophyllum in the Jurassic of Israel may have been able to branch into separate individuals. Pandey and Lathuilière (1997) doubted this and suggested that Gill had misidentified his Israeli specimens. Maybe so, but we’re pretty sure we have Epistreptophyllum here, and we definitely have budding. We’re always open to other ideas!
Here is another view of the specimen in its living position after the fall. I love the sweep of the vertical ribs as it made the bend.
To complete the tour of this specimen, here’s a view of the oral surface where the polyp lived. The radiating lines are the septa that extended vertically through the interior of the corallite.
Epistreptophyllum was named in 1876 by Constantin Milaschewitsch. Here is Plate 50 from that massive work. Epistreptophyllum is marked by the red rectangles. (Note the misspelling of the genus in the caption for figure 2.) I wish I knew more about Mr. Milaschewitsch, but his particulars are thus far not available. I can tell he worked in Moscow and St. Petersburg, Russia, but that’s all. If anyone knows more about this man, please add your information in the comments.
Gill, G.A. 1982. Epistreptophyllum (Hexacorallaire Jurassique), genre colonialou solitaire? Examen d’un matériel nouveau d’Israel. Geobios 15: 217-223.
Milaschewitsch, C. 1876. Die Korallen der Nattheimer Schichten. Palaeontographica 21: 205-244.
Pandey, D.K. and Lathuilière, B. 1997. Variability in Epistreptophyllum from the Middle Jurassic of Kachchh, western India: an open question for the taxonomy of Mesozoic scleractinian corals. Journal of Paleontology 71: 564-577.