That WAS a thought-provoking question Ceroill asked. Given that the Anime field is so vast and “complex,” I don’t blame you for not having an answer.
On a “unrelated” note:

Those are some good-looking women there at Kayo Dot.

As to your idea on the development of the human voice of the tsuchinoko, I think what you said is spot on. Sure, there are animals, like parrots, that are capable of being great mimics but snakes are not exactly known for that sort of thing. I think any of the vocalizations described for the tsuchinoko would be highly unusual for a snake, let alone human voices.

Concerning your inquiry on Japanese anime, I have to first off admit that this is one aspect of Japanese culture that I am not particularly well versed in, so I would have rather had someone here who is more knowledgable on the subject to answer your question. However in my opinion (I do have a passing knowledge), anime styles such as “super deformed” reflect a wide array of cultural aspects and sensitivities. So while I don’t think the tsuchinoko is the sole inspiration for that style, I wouldn’t be surprised if it had some influence. That is an interesting cultural observation you made, I only wish I was more informed to give you a better and more concise answer!

Finally, here’s a bit of cultural speculation: What do you think of the idea (just occurred to me) that the proportions of the tsuchinoko being an influence on the development of that peculiar style of anime called SD or Super Deformed?

You say that there is a group who seek it. Is there a general approach that they take? Not having been to Japan, yet, I wonder where I’d plan an expedition to look, actually it would be more like a pretext to get outta town and hang. Cheers.

PS, have you read Charles Mann’s “1491″? I am now and it’s altering my understanding of the way field science (archaeology and paleoanthropology in this case) and its interpretation work in the real world with some surprising new revelations.

I am very enamored with the stories of the tsuchinoko and the myths and folklore associated with it, indeed it is one of my favorite Japanese cryptids, yet I remain on the skeptical side as to its actual existence. To me, there are some key points that need to be looked at critically concerning the way the animal is typically described.

First off, the tsuchinoko is renowned for its ability to make great leaps of several meters. This is interesting as the snake is always described as quite thick in the middle, quite sturdy and heavy looking, which is not a good design for making such jumps. What to make of this? There was a good comment on the so called “flying snakes”, and this could offer a possible explanation, although accounts are quite clear that the snakes are jumping horizontally from a set position rather than gliding. It could also be the result of exaggeration or a misidentification of some other form of locomotion such as the “sidewinding” that some snakes do, or a particularly explosive strike at prey. And if you think the leaping is an odd feature, consider that there are reports of the snake taking its tail within its mouth and rolling along like a wheel.

Second is the shape of the snake, which as I mentioned is very thick in the middle. As someone else mentioned, this could very easily be caused by the witness seeing a recently fed snake. There was even a case some years back where someone claimed to have captured a tsuchinoko and it turned out to be just a gorged common variety of snake.

Third is the purported cases of the tsuchinoko’s wide range of vocalizations that range from whistles, to grunts, to chirping. Some accounts tell of their ability to even mimick a human’s voice. I feel this sort of vocal range would be odd for a snake to have developed, and I think instead this might be more exagerration or confusion of another sound for one made by the snake.

There are other reported seemingly magical abilities of the tsuchinoko as well, and so like other Japanese animals both real and imagined, I think it is sometimes hard to tell where the folklore ends and the facts begin. If there is a new species of snake out here in Japan, I am doubtful that it can do everything it is reportedly able to do. Of course there have been animals before that were very real despite being given fantastic or even supernatural descriptions, so I do not wholly rule out the existence of a new type of snake in Japan. There are groups out there who still actively search for the tsuchinoko and I would be thrilled for them to turn up a new reptile. I just think the more mundane possible explanations have to be given weight as well.

Although I have an open mind, I myself am a bit on the skeptical side of the actual existence of a new species of snake fitting the description provided from reports and the lore for several reasons. First, the description of the snake is always of one that is fat in the middle and fairly hardy and heavy looking, not at all the type of design I would think would be conducive to making the several meter long leaps it is reportedly capable of. Also, the snake is said to be capable of a wide range of vocalizations of the type that would be very odd for a snake to have developed. Some even say it is capable of mimicking a human voice. I won’t even get into the magical properties attributed to it through the ages.

These things in and of themselves probably do not rule out a new species of snake as we all know that native accounts of real ethnoknown species can often have some somewhat fantastic descriptions and yet they are based on an actual animal. I just think there are some possible mundane explanations for a lot of the sightings. Someone here already mentioned that the description of a fat middle body could possibly be caused by a snake that has recently fed. The jumping ability could be exaggerated, or a misrepresentation of some other form of unusual locomotion such as can be seen in the “sidewinder” snakes. The vocalizations said to be made by the snake could be exaggerated, the product of an overactive imagination, or even be caused by other strange sounds caused by something else during the sighting, and then mistakenly attributed to the snake. If there is a new type of snake in Japan, I feel it almost certainly cannot do everything it is said to be able to do and it would be interesting to see just what it CAN do and how it does move.

In the end, I am open to the idea of a new species of snake in Japan, but it is hard to say if this is the case when it comes to the tsuchinoko. It is hard to tell where any real creature might begin and where myth and folklore ends and so I think a critical approach should be taken. It could be a real snake, colored by folklore, I will not rule that out yet I think more mundane possibilities need to be looked at as well. Nevertheless, there are groups in Japan still actively searching for the snake and there are occasional rewards offered for a specimen, so who knows? Maybe it is the next new species waiting to be found.