Category Archives: Myrmecophiles

In situ Pella is the best kind of Pella

Finally got it! Evidence of Pella planifer behaving in its natural environment.

Pella planifer investigating the vicinity of Crematogaster activity.

Pella planifer investigating the vicinity of Crematogaster activity.

We know from work conducted in the Palearctic that species of Pella hang around the nest vicinities of their host ants, preying upon weakened workers and scavenging on whatever opportunities that may arise. But these observations were geographically limited and the few Pella species of North America were a behavioral enigmas.

Based on my own previous observations, it had been becoming clear that North American Pella exhibit similar behaviors and ecologies as their Old World cousins. That’s all dandy but there is nothing that can top visual evidence to support an organism’s behavior in its native environment – today, I’ve finally accomplished this.

Pella planifer biting and tugging at a Crematogaster queen in midst of colony recruitment.

Pella planifer biting and tugging at a Crematogaster queen in midst of colony recruitment.

Crematogaster wake for spring

There’s a Crematogaster colony that lives in my backyard where I’ve periodically searched for Pella planifer. I also use the colony’s activity as a proxy for ant activity. Before I set out to go collecting, I frequently check the activity of ants in my yard in order to assess how the collecting that day is going to be.

Ants active? Great, I’ll check foraging trail periphery for Pella today.

Ants not active cause it’s too hot? Too bad, maybe I’ll put off myrmecophile collecting until fall.

It wasn’t until around 1 PM that the Crematogaster began to forage, a little chilly today. Nonetheless, decided to check out the column for Pella later in the afternoon, hoping to snap some in situ action shots of Pella destroying Crematogaster workers.

For a second there I saw a scuttle out of the corner of my eye - not Pella but a free-living athetine of some sort. Maybe Acrotona?

For a second there I saw a scuttle out of the corner of my eye – not Pella but a free-living athetine of some sort. Maybe Acrotona?

Unfortunately, it was a little too cold today and the previous night’s drop in temp. didn’t help either, oh well. Still got some interesting shots of Crematogaster workers interacting with queens that had recently dropped their flight wings. This species of Crematogaster is polygynous, not sure but I interpreted this behavior as workers trying to recruit new queens. Oddly, the queens weren’t cooperating with the workers.

Crematogaster_5.iv.2014_2 Crematogaster_5.iv.2014_1

I heard some pleasing news today and it made my day.

This photo’s from Costa Rica. I think it’s a Microdon sp., checking out the nest entrance. Honestly, I know they’re myrmecophilous so I should be able to identify the genus from other hover flies, but the characters that define them are found in the wing venation, so kinda hard to check out in the wild.

Thanks to a comment by Martin, this fly was identified as a species of Lepidomyia. Martin also informed me that the larvae are unknown, but those of a related genus develops in decaying wood. Makes sense, this individual was scouting a tree hole opening, which was coincidentally occupied by an ant colony.

Whatever, gestalt is a taxonomist’s best friend anyways.

Gestalt betrayed me…

Microdon checks out an ant nest entrance.

Lepidomyia checks out a tree hole opening.

And, some more myrmecophiles from Sat.

Camponotus were preparing for colonial proliferation.

Reproductives patiently wait for the right moment.

Reproductives patiently wait for the right moment.

Some case-bearing leaf beetles can be found with ants, where they feed on nest refuse. I’ve previously collected adults and larvae from Arizona, Arkansas and Oregon. The ones from Arizona and Oregon were in the genus Saxinis.

I kept them alive. We'll have wait and see what the adults look like.

I kept them alive. We’ll have wait and see what the adults look like.

Poster child myrmecophile, Myrmecophilus, hey it’s right in the name!

An immature female, you can see her still-developing ovipositor.

An immature female, you can see her still-developing ovipositor.

The current revision that treats North American taxa, in my opinion, is not that reliable. I don’t think hind leg spine number is a stable enough character to be used in identification. I have seen taxa with unequal numbers between their hind legs. I think molecular data will give us an entirely new perspective, just as the research in Japan has. I suspect this is what people call Myrmecophilus pergandei.

There is some evidence to suggest that individuals develop according to the size of their hosts. Therefore, some species are known to demonstrate extreme size polymorphism. Could this really be the reason behind these observations?

There is some evidence to suggest that individuals develop according to the size of their hosts. Therefore, some species are known to demonstrate extreme size polymorphism. Could this really be the reason behind these observations?

More Masoncus!

The female yesterday was a little teneral. The ones today are fully pigmented, and look, an immature!

Masoncus_sp_blog4

Masoncus-season #2 begins

About a year ago I blogged about how I had started collecting a species of linyphiid spider with Formica ants that nest in my front yard. I left the post open ended, hoping that someone would have an idea of what the spider species might have been. I was picking up multiple life stages, both sexes and had accumulated over 40 specimens over the course of the field season. Given these statistics, it was hard for me to believe that these spiders were accidentally occurring with ants and became convinced these spiders were myrmecophilous.

A mature female Masoncus sp. wanders among its hosts.

At the time little did I know that I was to receive an email informing me that the spider may belong to the genus Masoncus and was directed to the research of Paula Cushing. She worked with a, at the time, new species of Masoncus that occurred with Pogonomyrmex in southeastern USA. Observations revealed that these spiders follow host trail pheromones to accompany host nest site switches. I contacted Paula and we believe that the species in my yard might be a new species, which had also been collected recently in Wisconsin.

Masoncus sp.

A mature female Masoncus sp.

Masoncus sp.

A mature female Masoncus sp.

Several of us are now working together to further understand the biology of Masoncus in relation to its hosts. As a part of this objective, we are currently accumulating material for gas chromatography-mass spectrometry (GC-MS) to compare guest and host cuticular hydrocarbon profiles (CHC). These spiders wander the nests freely, undetected, and may be acquiring CHCs from their hosts either passively or actively, essentially camouflaging themselves among the ants. On the flip side, these spiders may just “have no smell.” These are both commonly employed strategies to infiltrate ant colonies among arthropods. Either way, the GC-MS should tell us more.

More minis.

TA meeting, applied for money, reviewed a manuscript… Before I continue on with more pressing tasks, here are a couple more mini-clavs. These are from the KU collections.

Mini-clavs

Mini-clavs

And, something to stimulate your auditory senses while these little guys blow your visual fuse box.

Oh, and next time your lab gets dry ice.