A reader wonders if the creature in this photograph is a dead slug. From the photo we can tell that the creature has black coloration, a smooth exterior, a shape that is bulbous at the head but thins out towards the tail, and is small compared to the $10 bill our reader exhibited for size comparison.
Our reader adds that he cannot tell if the creature is really a creature at all, saying it could be “a slug or some sort of dropping.” If it was a slug though, he guessed that the yellow color we see surrounding the slug could be urine or a slug trail. Now, when it comes to a creature of this size, it is very difficult to give a specific identification. This is especially due to its lack of defining characteristics. Though given its shape, color and supposed texture, we could venture to say that is is either indeed a slug, or a leech.
Slugs are common garden pests that have evolved over time from the snail. They have incredible abilities and are quite intelligent creatures. For example, slugs can regrow parts of their bodies, including their heads! In fact, slugs are even able to “self amputate” to escape prey, according to AllAboutSlugs. Furthermore, slugs leave ‘slug trails’, as we call them, to find their way back to their dens underground where they sleep. Slug trails are not yellow though, so we doubt that that is what the yellow matter in our reader’s photograph is. It is more likely that it is urine or some other kind of secretion.
On the other hand, leeches are exterior parasites that live in freshwater bodies such as lakes and rivers, though of course there are exceptions. Some leeches even live on land. They attach themselves to their hosts, which consists of any animal larger than themselves, and suck the blood out using teeth that discretely sink into the victim’s skin. They also choose spots to feed on the host’s body where they are least likely to be found. Leeches grow in size the more blood they drink, which is a given as that is their primary food source. Although the creature in our reader’s photo does not appear as slimy as most leeches do, it is possible it dried out and that is why it died. Leeches do urinate, although we don’t know what color their urine is, so it is possible that the yellow matter in this case is urine, as it does not resemble dried blood.
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In any case, regardless if it is a slug or a leech, they clearly wandered in there by accident, as a dry home is not the ideal environment for either of the two creatures. It is also possible that the creature got carried in by something else, like a pet (if that applies to our reader) or on produce. Additionally, infestations of slugs or leeches do not occur, at least not in a household, so that is nothing our reader needs to worry about. And since the creature is already dead, it cannot pose any threat to our reader, unless he were to eat it, which is unlikely (we hope).
To conclude, it is unclear whether the dead creature in our reader’s photograph is a slug or a leech, but either way our reader should not have anything to fear in terms of infestation or for his safety and health. However, if more of these do appear, we invite our reader to send in another query with more pictures, and perhaps more context as that is always of great help.