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Slugs Mating

Monday’s post stated that the nature of the activity the slugs were engaged in was undetermined.  Since then it has come to my attention that had I been truly “naturally curious” and popped the bubble of slime, I would have had the rare opportunity of seeing two entwined slug penises.  Here is a descriptive quote describing slug reproduction.

Like all slugs, those in the genus Arion are hermaphrodites (possessing both male and female sex organs). They can reproduce either by self- or cross-fertilization, depending upon conditions and habitat stability. When two slugs mate with each other, they each simultaneously play the role of both sexes, exchanging sperm with their male genitalia. At times, the male sex organs of two slugs become entangled during mating and the slugs may bite them off in order to free themselves, a not uncommon sacrifice known as ‘apophallation.’ From then onward, the apophallated slugs are only able to reproduce as females. Arion subfuscus mates in the mid-to-late summer. Several days after mating, slugs will lay hundreds of 3-4 mm eggs in the soil, and die shortly thereafter. Although there is no parental care in this species, the eggs are imbued with a caustive agent called miriamin that serves in a large part to protect them from predation. In around a month, the juveniles hatch as small, pale-brown versions of their adult selves. They typically take at least 4-6 months to achieve sexual maturity, mating and dying themselves before the new generation hatches from the eggs.” (

7 responses

  1. Alice

    That’s a lot of interesting info. You’ll most likely be going on a slug hunt, Mary.

    September 22, 2020 at 10:19 am

  2. Diane

    Very interesting.

    September 22, 2020 at 10:20 am

  3. LOL🤣

    From Susan Gilpin


    September 22, 2020 at 11:46 am

  4. Well, who are we to pop someone else’s bubble!

    September 22, 2020 at 11:57 am

  5. Gaylee Amend

    fortunately, I’m speechless.

    September 22, 2020 at 12:31 pm

  6. Judy Ross

    Oh my! It’s a good thing I didn’t know the whole story behind today’s “slugfest” BEFORE I shared it with my online ZOOM class of 21 4th-graders. Yikes! I can almost hear the parent emails now. Let’s just say the clarification email will just stay between friends of Mary’s, okay?

    September 22, 2020 at 5:41 pm

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