Antroducing: the red ants of the Carpathian mountains (Myrmica ruginodis)

The second week of our holiday in Romania we would spend high up in the Carpathian mountains.We had traded in the brother and his family, for Kittenmancer's parents as our travel companions. They were quite amused by out antics so far and her father helped us out enormously by scrounging a few test tubes, because not only do these make more reliable housing, it's also a lot easier to scoop up escaping ants (from the bed) with a test tube than a scrap of paper and a brush.

Outside our hotel, I flip the first rock we see and lo and behold, it has ants under it! Little red ants start sluggishly collecting their pupae towards deeper in the dirt. They look exactly like the Myrmica rubra we have at home, but since we dug up their larger, darker cousins from the dunes the previous week, I had been reading a lot about this genus in an attempt to uncover their true identity. Thus I remembered that, while rubra is very common in Romania, the higher the altitude, the more they get replaced by Myrmica ruginodis. And, as we were above 1400 meter, pretty high in the Carpathian mountains, I was fairly certain what species we were dealing with, even though it was impossible to confirm (the differences between the two are really tiny, as in few and small).

M. rubra to the left, M. ruginodis to the right, spot the differences
(but not color: that's mostly lighting and preservation techniques).

Tempting as it might be to dig them up right away, a wiser course of action was to put the stone back. If we waited a few days for the ants to reclaim it and have their pupae soak up the last bits of warmth before the increasingly colder weather forced the colony into hibernation, we wouldn't have to dig as deep through the rocky soil.

We then took a walk to the nearby skiing area, called the Platosh Arena, to see how high we can go up the mountain for some spectacular vistas. Along the way we spot fallen trees and lone treestumps in the thick pine forests surrounding us. As much fun flipping rocks is, we were actually hoping to find Camponotus ants next and these 'carpenter ants' much more prefer decaying wood over some stone in the dirt. Yet every piece of rotten real estate we carefully peel apart only occasionally reveals some centipedes, a beetle or some wood-boring grubs. Not only is the lack of insects mysterious, we don't see any of big piles of sawdust typical for the Camponotus ants as they turn the rotten wood into Swiss cheese.
No snow when we were there. We walked up along E and then down right through the middle.

We hiked up the skiing piste, passing by some rather tacky dioramas depicting tales of folklore. Ofcourse little chance of finding any wood ants on this green meadow slope with few standing trees. It's white blanket of snow still a few months off, the place was abandoned save for some downhilling daredevils on mountain bikes and some kids trying out some even more dangerous looking sledding ramp. As far as we could look we saw foresty greens in the distance, though lower in the valleys there were deciduous trees mingling with the pines. Was that where all the insects were hiding? Were we simply too high up? We planned to investigate in one of our later hikes through the area.

View from the top.

After reaching the top, we did what what tourists typically do: take pictures. However, we were probably the first tourists there to catch an ant next: After only a few steps back down the side of the slope, looking down for sure footing, I spot something small scurrying across a molehill. It's a Myrmica queen! As this one too looks very much like a rubra, it's likely yet another ruginodis instead. Kittenmancer's dad got the honour of naming her, so it became 'Bambi', after one of the dioramas.

Just to be sure that the molehill wasn't an antnest in disguise we tried out this awesome folding shovel we borrowed from the awesome brother. Conclusion: no ant was going to hide from us underground for long (except if it wasn't there, of course).

We left the Platosh Arena, further along the main road and past tacky tourist hotels. There, on the roadside in the grass we spotted some rocks among the grass. Now there is a bit of a 'Goldilocks zone' to whether there will be ants under them or not: too small and they won't be embedded enough into the dirt, too large and the sun can't warm up the stone enough during the day. There also has to be vegetation nearby providing food for the colony. To show off my ant-hunting prowess to my girlfriend's parents,  I predicted that the big rock was going to have ants under it, likely the same Myrmicas as we had found before, but not the small rock.

A piece of prime ant real estate.

Moist grassy area with wild flowers and herbs.

Ants indeed: lucky guess. But also: lucky find! This colony had a lot more brood than the colony on our hotel's driveway and not just cocoons, but larvae too. And here we were also more likely to dig a hole without people complaining. Just keep an eye out for crazy Romanian car-drivers as we were right next to the road. We had to go back to the hotel for some more supplies like boxes and catching tubes, which meant all the ants were hiding in deeper parts of the nest by then. But we figured with our fancy new shovel, that wasn't going to help them for long.

We started digging and spreading the dirt out to pick out the workers and brood, while keeping an eye out for the queen. Myrmica queens are hard to spot, being only slightly larger than their workers. The best way to recognize them is for their much larger thorax as this was where their flight muscles used to be. The cold ground was making the ants sluggish, so they were moved into our collection box with ease. We even find a winged alate (an unmated queen). A bit of a mystery what she was still doing here (overslept her nuptial flight?), but she goes into the box nonetheless and we put her out of our mind as we focus on finding her mother. Still avoiding capture after 30 minutes and a big hole in the ground, we were close to giving up. But just like with the previous dug up colonies it was the 'one more look' that did it as her majesty revealed herself and was scooped up.

Back at the hotel we set ourselves up on the bed to move our new Myrmicas into a testtube. But the ants had warmed up by now and were not as docile anymore. Trying to murder the brush as their larger cousins did before and even the alate was brush-biting like the best of them. We decided to sift the dirt in the collection box, looking first for the queen and any worker carrying brood so at least the ants wouldn't try to escape their new home so much. Thus the whole colony was succesfully transferred and give a cotton swab dipped in fruity juice, settling them down. We named the queen Platosha, after the skiiing piste, and she and her workers wouldn't give us any more hiccups until after we got home.

Bambi hiding in the second catch tube to left, Platosha's colony in the bottom test tube.
Notice the size difference with the Myrmicas from the delta in the big bottle.
Also the Temnnothorax from Karaorman in their acorn in the left-most tube.

Later that week we went on our investigative hike down the valley in our efforts to catch a Camponotus species, joined by Kittenmancer's cousin and her husband (Cristian). We mostly walked over forest paths with tall pines looming over us on both sides, as I explained to them about ants. Their initial knowledge didn't go much past beyond 'little insects that ruin picnics' and the Romanian belief that disturbing an ant nest would cause rain the next day (I can imagine how the timing of nuptial flights has coaxed that idea along).

They were quite interested however and especially Cristian was getting anthusiastic. Romania is blessed with an exceptional variety of European ants, having both temperate species and more heat-loving species from the south. It also still has a lot of nature left and Cristian personally owns a piece of old-growth forest he was anxious to check for ants.

Every good investigation has a map.

In the meanwhile our investigation into the missing carpenter ants proved that we were indeed simply too high up, as we ran into several big lone workers crossing our path when we finally got near the valley. However, this blog post isn't about them (the next one will be), but about Myrmica ruginodis, who proved that they were the dominant species around here, as we again ran into them, twice.

First when we had a lunch break in the lush meadow in the valley at the end of our hike. I flipped another Goldilocks rock to show our travel companions the ants beneath. This time however, for a change, the queen was immediately spotted among a ton of brood, putting us in an unplanned collecting frenzy. Not as sleepy as the Platosha colony (it's a lot warmer down the valley), but four pairs of eyes and hands made the colony's abduction into our collection box go extremely quick. We would transfer into a test tube later back at the hotel with practiced ease and name the queen Shanta, after the youth summer camp we passed by on our hike that both Kittenmancer and her cousin visited when they were kids.

The second time we ran into our Myrmicas was a bit later that day when our investigative hike finally yielded a Camponotus nest with a huge colony of the little red scrappers right next to them in the same wood log. All nests we had found so far were under rocks in moist grassy areas and had only a few hundred workers, but this one had several thousands of them, unhappy with having their house compromised and taking it out on their neighbours.

Needless to say that we were pretty much done with Myrmica ruginodis by now (even the ones under the rock at the hotel) and moved on to different species, starting with the ones we had just found. Read about that rescue operation in the next blog post!