Illinois terrestrial leech

schmiggle

Arachnoprince
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I found a description from the 19th century of a large (up to 7") terrestrial leech from Illinois that feeds on earthworms. It was apparently fairly common at the time--56 collections were made between 1876 and 1890. It was described at the time as Semiscolex terrestris, but the genus Semiscolex and family Semiscolecidae as currently defined are confined to South America. This isn't surprising in and of itself--worm taxonomy is a mess--but it makes it impossible to find any more recent findings or descriptions of the leech.

Does anybody know anything about this? Alternatively, do you know anyone who I could talk to? I had thought terrestrial predatory leeches were restricted to South America and east and southeast Asia, but it would be really cool if you could find them in Illinois (and big ones at that!)
 

MTA

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There are some terrestrial Haemopis species in some parts of the eastern US.
 

schmiggle

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There are some terrestrial Haemopis species in some parts of the eastern US.
Ah, I figured Haemopis was blood-sucking largely because of the Latin root haem- in the genus but partly because the easiest species to find is called the horse leech (despite being a predator of invertebrates--whoops). I'll look into those.
 

schmiggle

Arachnoprince
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Here we are. I think three species have been described so far: Haemopis terrestris, in the Midwest east to Ontario (but not south of Ontario), is entirely terrestrial and often found far from water; H. septagon, in the Southeast from South Carolina to the southernmost tip of Virginia, prefers water-land interface habitat; and H. ottorum, from the pine barrens (probably) of New Jersey, which has similar habitat preferences to H. septagon. H. ottorum is up to a foot long! I would never have guessed there's a leech in the US as big as Mt. Kinabalu giant leeches.
 

pannaking22

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Poke around on the Illinois Natural History Survey page. There may be someone that has locality info if you want to go looking. I'm trying to think who works there who works with leeches or at least would be coming across them fairly frequently.
 

Amybio

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I found a description from the 19th century of a large (up to 7") terrestrial leech from Illinois that feeds on earthworms. It was apparently fairly common at the time--56 collections were made between 1876 and 1890. It was described at the time as Semiscolex terrestris, but the genus Semiscolex and family Semiscolecidae as currently defined are confined to South America. This isn't surprising in and of itself--worm taxonomy is a mess--but it makes it impossible to find any more recent findings or descriptions of the leech.

Does anybody know anything about this? Alternatively, do you know anyone who I could talk to? I had thought terrestrial predatory leeches were restricted to South America and east and southeast Asia, but it would be really cool if you could find them in Illinois (and big ones at that!)
I found this leech in the middle of my backyard this morning. I live in Worden, Illinois.
 

schmiggle

Arachnoprince
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That's pretty cool. Guess it's probably Haemopis given the conversation above. Did you keep it? Have you tried feeding it?

On the other hand, I'm not an expert, and it's always possible it just fell off of a deer or similar and was trying to get back to water. I will say, though, that it looks rounder than I would expect for an aquatic blood sucking leech.

Pretty cool you found this thread, I had forgotten about it. Maybe one of these days I'll make it out to the Midwest and try to find one of these.
 
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