A couple of weeks ago I mentioned to some colleagues here at The Field Museum that I wanted to get some sizable snails or slugs for an upcoming presentation ("Meet a Scientist"). Margaret Thayer, Curator of Insects, replied, "I saw a bunch of fairly large slugs on my porch the other day. Shall I bring you some?" I gladly accepted the offer, assuming that she would bring one of the several introduced slug species that have long been known to live in Chicago and the suburbs. When Margaret delivered the slugs I was surprised. Sure, this was an introduced slug, but none of the expected ones. The family it belongs to (Milacidae) is easily recognizable and not native to the Americas. I knew immediately that this was a new record at least for Illinois where no members of this family had been found before. To figure out the species is trickier, since many of these slugs look rather similar externally and, in addition, display a fair amount of intraspecific variation. One has to dissect mature specimens and analyze their hermaphroditic reproductive organs to make a reliable identification. Luckily Margaret's specimens turned out to be mature. The result of the dissection was another surprise: this was not one of the several Milacidae species known to have been widely introduced to places, including the U.S., outside their original European distribution areas but a species that had never before been recorded in the Americas.
Naturally this sparked my interest. Who knows what else leaves its slime tracks around Chicagoland?
Therefore, Field Museum employees, volunteers, associates, friends:
If you have a yard, garden, compost heap or merely a planter on the balcony there is a good chance you share that space with slugs who like your lettuce and petunias at least as much as you do.
But don’t just cut the critters through with your garden shears or kill them with slug killer from the garden center — at least not all of them. Put a few of them in a clean jar with a tight lid. You may add a moistened (but not dripping wet) piece of paper towel. Put the jar in the veggie crisper of your fridge until you come to the museum (with the slugs, of course).
Then email me at firstname.lastname@example.org or call me at extension x7577 and I’ll take the slimy critters off your hands.
!!!!!!!!! Please note: I will be out of town from Aug. 3 to Aug. 25. Consequently, slug deliveries can take place until Aug. 2 or after my return !!!!!!!!
I will identify the slugs and voucher specimens will be deposited in the Field Museum’s Mollusk Collection. If enough of you from around the city and the suburbs participate, our little ad-hoc slug survey could render interesting results.
Go gett’em and thanks in advance for your help!