Tuesday, 19 April 2011

Titanic Turtles of Tele

Ndenki is spoken of as a truly tremendous freshwater turtle in parts of the Congo River drainage and especially around Lake Tele.This is another matter of some confusion in Cryptozoology. Some individual softshell turtles of the known, identified species can grow to quite enormous sizes. A pertinent example comes from Darren Naish's blog:

Anyway, Asia isn't the only continent with giant softshells. There are also giant African species (or one anyway: the African softshell Trionyx triunguis), and in an October 2009 post on the SA Reptiles discussion board, forum-user Herphabitat posted several photos of a huge, dead softshell he and colleagues discovered on a peninsula in the mouth of the Congo River. From a distance, they first assumed that the carcass was that of a dead sea turtle (perhaps a Leatherback Dermochelys coriacea). On discovering that it was a softshell, they assumed that it had died further up-river and had then been washed down to the edge of the Atlantic. However, this assumption isn't warranted, as T. triunguis inhabits brackish waters in places, and has even been captured 3 or 4 km out at sea (this was close to the mouth of the Gaboon River: Ernst & Barbour 1989). T. triunguis is a widespread softshell, occurring from coastal Turkey, Israel, Lebanon and Syria all the way west to the Atlantic coast of the Congo region.



As you can see from Herphabitat's photos, the animal was a pretty impressive beast (his photos of the animal's skull [one shown below] confirm, by the way, that it was indeed a T. triunguis). Its length along the curve of the carapace (known as the CCL, or curved carapace length) was 55 cm, and the total length was given as 106 cm. Its mass was estimated at over 60 kg. Very big indeed - and bigger than most measurements given in the turtle books. Ernst & Barbour (1989), for example, give a maximum length of 95 cm for this species. However, some sources give a maximum length of 112 cm. Again, I hope this brings home the point that softshells - which are relatively familiar turtles to many people - aren't all dinner-plate-sized or smaller; some are giants, among the largest of turtles.
















While we're here... it's been suggested that there might be monster examples of T. triunguis whose lengths well exceed 1 m. In his 1987 book on the mokele-mbembe, Roy Mackal wrote about the 'Ndendeki', a giant turtle of Lake Tele (and perhaps the surrounds) in the Congo. Local people didn't know much about it - other than that it was a turtle and that it was very large - but an estimated diameter of a ridiculous 4 or 5 m was suggested (Mackal 1987, p. 267). Mackal and his colleague Marcellin Agnagna both assumed that exaggeration had occurred, and that a more reasonable size might be about 2 m (this is for length [of the softshell carapace] and not diameter). That's still pretty incredible - though certainly not impossible - and really needs verification [adjacent Ndendeki reconstruction from Mackal (1987, p. 271)].



Anyway, full credit to Herphabitat for his excellent photos. Please visit the SA Reptiles post to see more images and more information. Thanks to Markus Bühler for bringing this to my attention.



http://scienceblogs.com/tetrapodzoology/2010/01/giant_african_softshells_-_wow.php



The latter link goes to the original article and it includes the statement:
"The boney part of the the carapace measured a CCL of 55cm and CCW of 54cm. The total length of the soft shell was CCL: 106cm"

Some confusion of the length of the gigantic turtles as stated by the Natives is probably the result of mismeasure again. In turtles, the overall length is not important to measure but the length of the shell is. In a softshelled turtle, it is entirely possible for the head and neck to stretch out as far again as the length of the shell: hence a turtle "Only" a meter and a half over the curve might be reported as three meters long overall (Which is evidently the allegation for really big ones both in Africa and in South Asia)
















Now for the part which I definitely wanted to get across: THIS IS NOT CRYPTOZOOLOGY. WE ARE IN ALL CASES STILL TALKING IN TERMS OF KNOWN SPECIES OF TURTLES ONLY!







Best Wishes, Dale D.








7 comments:

  1. On an associated note, Vietnamese scientists are taking tissue samples of the Hoan Kiem turtle to see if it is a new species but the DNA testing results are not confirmed against all candidates yet and the announcement that the turtle is a new species is premature.

    http://english.vietnamnet.vn/en/science-technology/7350/hoan-kiem-turtle-is-a-new-species.html

    Hoan Kiem turtle is a new species
    VietNamNet Bridge – Dr. Tran Binh, Director of the Institute for Biological Technology, on April 18 told VTC News that the institute had finalized the DNA test of the legendary turtle in Hanoi’s Hoan Kiem Lake.
    “We will report the test results to Hanoi authorities and the information will then be widely announced to the public,” Dr. Binh said.


    According to Binh, Hanoi authorities planed to announce the DNA test results later this week.


    “Our test results are not different from previous statements of Vietnamese experts. The turtle is feminine gender and a new species. It is not a Chinese or Dong Mo turtle species,” Dr. Binh added.


    Binh said the turtle genetic sample will be sent to the World Gene Bank in Switzerland.

    “After the World Gene Bank receives the sample, Vietnam can make public that the legendary turtle in Hoan Kiem Lake is a new species, named Rafetus Vietnamensis or Hoan Kiem turtle,” said Binh.

    Binh said the turtle may be sourced from the Red River from millions of years ago.


    Dr. Bui Quang Te, chief of the turtle treatment group, said that the turtle’s health is very good now. “We are going to complete our treatment mission later this month,” he confirmed.


    He repeated that the urgent task is cleaning up Hoan Kiem Lake, so the ancient turtle can return to its clean natural environment. However, the cleaning process seems to be slow.


    Earlier, experts suggested using carbon fibers, specialized sterilization substances and ultrasound waves to kill algae and bacteria in the lake.


    The problem in this case is that the Chinese turtle the scientists were testing against is NOT the species the turtle has been identified as and the one it should have been tested against.
    http://en.wikipedia.org/wiki/Rafetus
    quote:
    "Rafetus leloii (the Hoan Kiem turtle) has been proposed as a species, but is no longer regarded as a valid taxon; it is now considered a junior synonym of Rafetus swinhoei.[1]

    [1]^ Farkas, B and Webb, R.G. 2003. Rafetus leloii Hà Dinh Dúc, 2000—an invalid species of softshell turtle from Hoan Kiem Lake, Hanoi, Vietnam (Reptilia, Testudines, Trionychidae). Zool. Abhandl. (Dresden), 53: 107-112.


    Best Wishes, Dale D.

    ReplyDelete
  2. Very interesting. Thanks for sending the information. It is a large (and thick!) Trionyx, presumably triunguis, considering its size. I agree that the various measuring standards make it difficult to make comparisons. Ernst and Barbour are citing the carapace length rather than total length, and I can only presume that their source for the 95 cm figure is using the standard straight carapace length rather than the curved carapace length. If so, it's possible that some turtles with a SCL of a meter do exist. I'm assuming but not certain that SCL was the standard for older British-trained herpetologists like Loveridge in the 1950s; if not, the Harvard Museum of Comparative Biology may have clarified the standard used before publication. I've read the part of the Loveridge and Williams paper cited by Ernst and Barbour that refers to pancake tortoises, but I don't have a copy here (Arthur Loveridge and E. E. Williams, 1957. Revision of the African tortoises and turtles of the suborder Cryptodira. Bull. Mus. Comp. Zool. Harvard 115:163-557). Can someone clarify that point?

    ReplyDelete
  3. By "Somebody Here" you mean Dale: Darren has a separate (and widely respected) blog of his own. Both of us are referring to a third blog posted by "Herphabitat" and he is the one who was at the site of the African turtle mentioned, and was overseeing (or at least a party to) taking the photographs and the measurements: he was the one that kept the skull and I believe he is the one making a reference to Ernst and Barbour. I do not have access to that work myself but probably Darren does: The links provided above do go directly to Darren's blog and also to the originating blog with the notice from Herphabitat.

    The statements made by Native informants about giant turtles were taken down by Roy Mackal are published in a book about looking for living dinosaurs in the Congo basin; and the giant softshell turtles as described would be truly incredible if the dimensions that were alleged would be true. It is conceded by all parties that the figures given by the Natives are very badly exaggerated when they are talking about turtles three and four meters in carapace diameter, six to eight meters or more counting the outstretched neck. Most experts pick up their suitcases and leave in a hurry with a crisp "Good Day to you!" when they hear that part.
    The south Asian turtles are also alleged to grow very large, as big as an oceanic leatherback turtle in the Ganges according to the stories thereand the proponents of the Hoan Kiem turtle's special status have stated that it is the largest known turtle on earth. Those statements are also generally taken with a grain of salt.

    And thank you most especially for your very quick and quite knowledgeable reply.

    Best Wishes, Dale D.

    ReplyDelete
  4. Thanks, Dale. I have read the other blog posts you provided. My question referred to the degree SCL vs. CCL was/is standard; I have assumed the former.
    Rosemary
    http://chelonianconnection.blogspot.com
    Chelonian Connection: An independent turtle behavior lab since 1979

    ReplyDelete
  5. And I would agree, but that would be a point better fielded by Herphabitat, the original poster in this case. And I do thank you once again for your interest in the matter.

    Best Wishes, Dale D.

    ReplyDelete
  6. Personal Message from Richard K to my email this morning asks if the larger ones reported by the natives (the body section as 12-18 feet long is alleged) might not be the Mokele-Mbembe variant seen as a "Snake-strung-through a Turtle" and as added to the Plesiosaurian Taniwhas blog entry before-especially since it is obvious that the body part in that Traditional African representation is depiced as exactly the same as the turtle's body in the corresponding Traditional African representation at the start of this blog entry. My reply to him was that it would make more sense that way and that turtle-shaped and plesiosaur-shaped water monsters are often confused. In his book In the Wake of the Sea-Serpents, Bernard Heuvelmans created the category of Father-of-All-the-Turtles but then said it was an equivocal category, reports might otherwise be considered in the Plesiosaur-shaped category. And it is my belief that some reports of "Little Plesiosaurs" from South America are instead also a different sort of softshelled turtles.

    Best Wishes, Dale D.

    ReplyDelete
  7. This is a very informative article. I am glad to have discovered your blog.

    Thanks,
    Olive Ridley Sea turtle

    ReplyDelete

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