TravelFeedTravelFeed Logo

Mosquito/fly hybrid (Mikiola fagi) larvae & slugs (Arion ater) weird behaviour - Basque Country 🐌🌳

November 2022 · 2 min read · Autonomous Community of the Basque Country

I start this article by saying that if anyone knows for sure what kind of behaviour the two specimens of slug are carrying out, please share it in the comments.

Going into the mountains.
Going into the mountains.

As you know from previous articles, on my travels around the Basque Country I usually spend several days walking through the Basque forests, feeling Nature and exploring its native flora and fauna.

Entering a deep beech forest.
Entering a deep beech forest.

When I was walking for some hours I noticed for first time in my life some beech leaves with bumps on its surface that I didn't know what exactly they were at that very moment.

Beech leaves with bumps (1).
Beech leaves with bumps (1).
Beech leaves with bumps (2).
Beech leaves with bumps (2).

Now I know that those lumps are called "galls" and are made by an hybrid of mosquito and fly (Mikiola fagi) that lay their eggs on the leaves and their larvae feed within the tree/plant leaf tissue.

Even though inside these galls there is, usually, a living bug feeding on it, interestingly, it's not harmful to the general well-being of the plant or tree (as a general rule).  

I continue into the forest.
I continue into the forest.

After walking another couple of hours I reached an area of the forest covered with dry leaves, which was the place where I met the main protagonists of this article.

Common slugs (Arion ater) on top of that ball of compact mucus.
Common slugs (Arion ater) on top of that ball of compact mucus.

At first I thought they were carrying out some mating ritual or even reproducing, but after reading more about slugs, I am not so sure.

Don't Forget: Get Travel Health Insurance!

To make your trip a worry-free experience, TravelFeed recommends SafetyWing Nomad Insurance. It provides comprehensive health coverage while you travel, so you can focus on exploring, not the unexpected. Get a quote here

Slugs are hermaphrodites (they can fertilize themselves and also use either of their two sexes with another specimen to reproduce, according to National Geographic), but if you look closely, neither of them have their sexual/reproductive organs outside (they can be seen from naked eye).

Perhaps inside that ball is their new progeny but, according to what I have read, slugs are born buried in holes so I still have the doubt about what they were doing there.

Video recorded with Samsung Galaxy S20 Ultra 5G camera.

Photographs taken with my Samsung Galaxy S20 Ultra 5G camera.

Travel Resources for your trip to Spain

Recommended by TravelFeed

Flights: We recommend checking Kiwi.com to find the best and cheapest flights to Spain.

Accomodation: Explore the best places to stay in Spain on Booking.com, Agoda and Hostelworld.

Travel Insurance: Medical emergencies abroad can be pricey, but travel health insurance is not. We always use SafetyWing for affordable and reliable coverage.

Transportation: Use 12go and Omio to find detailed bus and train schedules, making travel planning easier.

Car Rental: For hassle-free car hiring, DiscoverCars is our trusted choice with a wide selection of vehicles.

Internet: Got an eSIM compatible phone? Airalo is perfect for reliable internet access during your trip. Just install it before you go, and you're set!

Day Trips & Tours: We recommend GetYourGuide for a variety of well-organized and enjoyable activities.

Tickets: Save on entrance fees in Spain with Klook and Tiquets.

Travel Planner: Need a hand planning? Our free travel planner chatbot is your personal guide to Spain. Chat now.

Disclosure: Posts on TravelFeed may contain affiliate links. See affiliate disclosure.


Share this post