While stalking ants in the southern Australian state of Victoria, I encountered one minuscule species over and over again. Another stone, another nest. It was a nearly translucent little dolichoderine:
I didn’t think much of it. The insects resembled- in appearance and odor- the ubiquitous Tapinoma that is so abundant elsewhere in the world. That I stopped to photograph it at all has more to do with, what- that I’d lined up the aesthetics of solid ant nest shots? I can’t even remember. It certainly wasn’t any realization that what I was shooting was perhaps interesting.
Yet looking at the photos yesterday evening, something didn’t quite add up for a Tapinoma. The petiolar node was scalar, and there weren’t many records for Tapinoma in that region.
Consulting Steve Shattuck’s excellent Australian Ants, I checked relevant characters for Doleromyrma. Clypeal setae curved: check. Petiole with scale: check. And so it was:
Doleromyrma, although frequently encountered, has received little attention in the published literature. They occur most commonly in dry forested areas, including coastal scrub or heath, where they nest in soil, under rocks or rotten logs…
A Google image search turned up a few images of preserved specimens, but not a single photograph of a living Doleromyrma. Am I really the first person to photograph this common ant in the field? Perhaps so. Or at least, I may be the first person to identify the live photos as such.
If so, it is my great pleasure to introduce the first living photograph of a Doleromyrma queen:
And, cropping in, the first living photograph of the queen’s mites:
So often it’s the little brown things, the ones I never think twice about, that end up being the interesting stories.
Note to self: stop pre-judging the insects.
Great photos and story, Alex. I always love a great story, especially with mites.
+1 for the fancy red arrows too !!
I’m kind of surprised that Dave hasn’t chimed in. Mites, you know.
Unfortunately, very little is known about mites on Australian ants, many of the names are almost unpronounceable and harder to spell correctly than Doleromyrma, and the existing literature is mostly ancient and minimalist.
Based on what is known and what I can see in the picture, the mites are probably in the Aenictequoidea and in either the Ptochacaridae or Messoracaridae. At least Messoracarus is mellifluous and no doubt the type species came from a Messor (or what would have been one in 1911). Ptochacarus is good for clearing the throat. In any case, I would love to retire and work on these mites. Looks like one of them is in a good position to steal some regurgitated food.
I don’t blame you for almost skipping over them – for some reason, most Dolichoderines have what looks to me like a very generic ant form. As such, I don’t find them quite as exciting as others! And I seem to not be the only one, if the lack of scientific material on this genus is any indication.
Ah, but the thing about Dolichoderines is their colonies. By saving resources from not overinvesting in cuticle, they are freed to make a great many more individuals, thus creating massive armies for world domination.
Great photos, as per usual. I always feel it’s a shame these less charismatic species receive less research effort. It often seems like when people look, they find something interesting, it just remains for us all to start looking!
PS, what sort of size are the queens and workers of this species?
Thanks, Henry! These are really tiny. Queens are maybe 4mm, and workers 2mm.
That’s awesome! The photo of the living queen of course, and the fact that your photography skills have so progressed that your pictures are now living… 😛
Is this actually a Doleromyrma? http://www.nelsoncitycouncil.co.nz/darwins-ant
Because if so, it would seem that someone has beat you to a picture, assuming the ant is actually alive!
Yeah, I saw that photo when searching around, but it’s too elongate for Doleromyrma. Instead, that’s a stock-standard Argentine ant Linepithema humile.
I thought that might be the case!
Is it just me, or is that genus a real tongue twister…?
I kept typing “Deloromyrma” in the draft.
So, a finger twister, at least. But then for me, any typed word is!
On the other hand, when spoken, I find that Doleromyrma has a lovely, sonorous quality that easily rolls off the tongue.
And it reminds me of “Bolero” — very sensual.
How do the mites stay on the ants without being removed? Do they anchor themselves really tightly? Stealth tactics?
There are some mites with setae modified as suckers that attach to insect cuticle (that could be what these mites are doing – resolution is too low to be sure). There are some that secrete a glue from their bums that hardens into a stalk – they look like tiny lollipops sticking out from the insect. Some stab into the cuticle and suck their blood. Then there are a number with bizarrely modified bodies that fit closely around an ant tarsal or antennal segment. But if I’m correct about what these mites are, they just hang on with there feet and probably use a chemical to make the ants oblivious to their being not an ant. Those are the kind that would be most fun to study.