Infected Slugs: Case #2

Not many days after I discovered the first case of parasitic infection among my slugs (Lehmannia valentiana), I spotted two more on the same night. In this post I'll discuss the first of these. Unlike Case #1, Case #2 appeared to be in a different stage of development. The slug did not have a boil-like growth on its body. Instead, the growth suggested the ordered, somewhat circular arrangement of eggs on the skin. Of course I can't verify this, but that's what it looked like to me. The growth itself was not simply yellow or yellowish-white, but a greenish-yellow, almost putrid color, and seemed to be a cluster of matter on the surface, not a protuberance as in Case #1. Also, I knew to look for excess mucus on the ground, which enabled me to trace the slime trail to the infected slug. This method served me well in subsequent cases. An additional contrast to Case #1 was the fact that this slug was probably in an earlier stage of parasitic development and therefore, while it did secrete more mucus than normal, its movement was not hindered, nor were its tentacles retracted and darkened. In fact, it behaved like a healthy slug. I apparently came upon Case #1 in the last stage, just before it died.

The first clue.

There were no obvious bulges in this slug's body. Like I said, it looked healthy except for the growth and the excess mucus.

You can see he's leaving quite a trail of slime.

No, I don't know what that clear ribbon is to the left of the growth. Probably just a thread of mucus. It shows up in the rest of the photos.