Large Japanese Carnivorous Mountain Leech

I encountered this animal while hiking in the rain among the mountains near Okabe, Japan (east coast, central Honshu) with my friend and co-worker Takaaki Futami. As we set out to climb a high and rugged peak near the coast, I commented to Takaaki that I hoped we might encounter a giant carnivorous leech on our outing. I was optimistic as my past two encounters with this animal had occurred while hiking on wet and rainy days in similar leaf littered forests. Only one hour into our hike I was delighted to spot the telltale brown and orange markings of a giant leech moving through the leaf litter at my feet. This was my first encounter with one of these animals while it was prowling for food as the previous two leeches I had seen were both busy ingesting giant Japanese earthworms as large as themselves when I found them (please see my YouTube video titled Japan Mountain Leech vs. Giant Earthworm to learn more). Takaaki and I were startled to see just how fast this animal could move when disturbed. It had been my intent to film the animal naturally as it was casually moving along the forest floor, though I quickly found that my only chance to view this animal would be quickly lost lest I carefully try to detain and hold it. I apologize for the poor quality of this video which was shot under bad lighting in a dark forest and by an overly excited cameraman. I never squeezed the leech hard and it is my hope that the animal escaped without damage. The next time I meet this animal I will try to not disturb it while attempting photography.

While most people are familiar with the bloodsucking form of leech, the carnivorous leeches do not gain sustenance in this manner and instead use their large jaws to swallow prey whole. This animals favorite food is earthworms which are driven (flooded) from their underground lairs during heavy or prolonged rains and become easy targets for wandering carnivorous leeches. I am by no means an expert on this subject and welcome any corrections and comments which may correct any errors on my part or help better identify this animal. The limited research I have done seems to indicate that the scientific name for this phylum is Pharyngobdellae.


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~ by softypapa on May 24, 2009.

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