We received a question from a reader who found some sort of larvae in his house. One was found in the hallway, and the other was found on the carpet by the baseboard. The reader says the larvae are white and red on top and green on the bottom, and this can more or less be seen in the photo he submitted along with his question. The reader also reports that the larvae has eight to ten legs. We think our reader found grub worms, which aren’t worms but scarab beetle larvae, so that answers one of his questions. However, he was also curious where the larvae came from, so we’ll address this topic as well.
First, here is the picture the reader submitted:
We aren’t entirely sure why this larva has a patch of green on its underside, but this definitely looks like a grub worm, the fat white larvae with brown heads that we have written about several times before. The strange thing about our reader’s situation (which we will return to shortly) is that he found them inside his house, and grub worms are almost always found outside, mostly in lawns, but they turn up in other places, like mulch piles. If our reader cares to check, he’ll notice that the larvae pictured in these other articles looks very much like the creature in the above image. Once more, the green on its underside is unusual and something we haven’t seen before, but there are tens of thousands of different scarab beetle species, so it is not as if they all look exactly the same. Also, in the above image, it almost looks like the green patch is some sort of stain that is not a part of its natural body color, but we aren’t exactly sure how this might have happened.
|No Paywall Here!
All About Worms is and always has been a free resource. We don't hide our articles behind a paywall, or make you give us your email address, or restrict the number of articles you can read in a month if you don't give us money. That said, it does cost us money to pay our research authors, and to run and maintain the site, so if something you read here was helpful or useful, won't you consider donating something to help keep All About Worms free?
Even with the color set aside, it is also strange, as mentioned above, to find a grub worm inside, but there are of course ways that this could happen. Grubs are quite common – problematically so, as they cause lawn damage – so if a relatively large population lives around one’s home, they could manage to get inside somehow. Even though a house is an unnatural place for them to gravitate toward since they live underground, they might still manage to crawl inside. Occasionally fluctuations in weather or moisture levels will drive insects and larvae inside. The grubs might have also been brought inside by accident, either by a pet or person. Dogs sometimes eat grubs, for example, so if our reader has a dog, perhaps it brought one inside in its mouth, but then didn’t end up eating it. Obviously, we don’t know exactly how they got inside, but our point is that there are clearly ways that this might happen.
One final note before we conclude. If our reader did find a grub, it can only have six legs, just like all beetles (and insects in general). Some larva appear to have more than six legs, but the extra appendages are in fact only prolegs. Grub worms actually don’t have prolegs, so perhaps our reader simply miscounted the number of legs on the creature he found, or he is confusing a part of the grub’s somewhat chunky body for legs.
So, despite some complicating factors, it seems like our reader found grub worms. Since a house is not a good habitat for them, this should only be a one-time (or at least rare) occurrence. If our reader wants to know more about what he found, he can research local species of scarab beetles, but perhaps knowing that he found grubs is enough for him.