Blapstinus, not welcome

Pogonomyrmex harvester ants dump scraps outside their nests.

Pogos at night.

Pogos at night.

For scavengers, this can be a lucrative place to visit for a meal. Tenebrionidae are frequent visitors. During our trip to TX this past summer, Blapstinus were very diverse and abundant around Pogonomyrmex nest entrances at night.

Blapstinus just eat trash so they’re a benign existence, but nonetheless are not welcome in the eyes of the ants.

This Blapstinus is not welcome.

This Blapstinus is not welcome.

New Tarsal Formula for Aleocharinae

It’s funny how life works out sometimes. Back in the day, tarsal formula was THE way to classify aleocharines. It’s a nice idea, very numerical and exacting. But, we now know, and this stinging fact is becoming more and more apparent with each additional study, that tarsal formula is super homoplastic and usage needs a bag, not a pinch of salt when considering.

Another addition to the aleocharine tarsal formula collage: 3-4-5!

Fore leg from this strange undescribed 3-4-5 Neotropical lineage.

Fore leg with 3 tarsomeres.

Script for comparing two matrices of equal dimensions

https://sites.google.com/site/staphylinidae/research-methods/script-for-comparing-matrices

Thanks to Boryana for writing this script for me.May be silly to the more computationally inclined, but I thought I’d share this in case there wasn’t already a way to do this that’s available.

Myrmecophily is a spectrum

Sometimes in the literature I come across definitions of myrmecophily that are quite restrictive, limiting the phenomenon to the most integrated members of the niche. I strongly think that myrmecophily is a spectrum, ranging into those that are more loosely associated with ants. If we don’t consider the entire spectrum, we miss the entirety of an ecosystem centered around an ant society.

From Texas again. This is Araeoschizus, a tenebrionid. These guys are loosely associated with ants, but they seem to have a tendency to be found with them. I often collect them with a variety of ant species. This trip, I observed them actively following Solenopsis (?) foraging columns at night for the first time. This adds to the complexity of Araeoschizus natural history.

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This one from Monahans Sand Dunes

This one’s from Monahans Sand Dunes

Adaptations for walking on plants

I would argue, the most under-appreciated niche among Aleocharinae are the myriad of associations with plants. Naturalists wouldn’t associate aleocharines and probably staphylinids in general as being associated with plants, but of course, the ecologically promiscuous aleocharines have managed to evolve plant-associations multiple times. Although they never really take off in number of species, the ways they associate with plants are rather intriguing.

There are those that eat pollen, such as Platandria, Microlia, Amazoncharis, Polylobus, Oxypodinus, Heterotaxus. Himalusa eats foliage. There are some stranger ones still that are predaceous in the confines of inflourecsens and leaf rolls, such as Charoxus, Ctenopeuca, Heliconandria, and Polycanthode. And then those that seem to be openly predaceous on foliage, like Oligota and Leucocraspedium Leucocraspedum (thanks go out to Margaret for pointing out the spelling error for the genus).

Below I quickly put together some adaptations that you can find on the fore leg morphology of plant-associated aleocharines.

Adaptations in the fore leg of Aleocharinae associated with plants.

Adaptations in the fore leg of Aleocharinae associated with plants.

Spines appear to be a popular theme in aiding with grip on a smooth surface, as can be seen in the pollen feeding Amazoncharis and Heterotaxus. Notice that Amazoncharis has stubby modified setae on the ventral surface of its tarsus in addition.

Heliconandria peoechma, on the other hand, lives in the leaf and flower rolls of Heliconia spp. Here, they likely prey on soft bodied organisms and participate in lapping up biofilms for microscopic food items. This species has additional fuzziness on the basal-most tarsomere and a modified tarsal claw. The tarsal claw is ventrally swollen, and has an additional facet which adds surface area.

Lab trip contributes to a carabid pub

A new study by Erwin and Zamorano reviews the Neotrpical Lachnophorini, which includes the enigmatic species pictured below. The image was taken by myself on our lab trip to Costa Rica. We were all collecting on a rock face seep for hydrophilids and I captured the imaging thinking, “oh, pretty carabid.” Later the image made its round to Terry and was able to contribute to his recent pub.

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Below, Andrew and Crystal are collecting at the seep. I doubt carabids were collected.

Erwin&Zamorano2014_Lachnophorini_Neotropical2

Rove beetles get parasitized too, just like everybody else.

I haven’t looked at these images in a long time. These are pictures of Exallonyx,  staphylinid parasitizing Proctotrupidae wasps. I was into trying to rearing these out in college. I would find them by collecting third and final instar larvae in the spring and rearing them out to see if I got any wasps. You’ll see from the images bellow, but the number of individuals are host size dependent, and emerge in a characteristic manner.

I’ve reared three species out on various occasions from 2007-2008 which I’ve uploaded bellow. The first two species emerged from Philonthus larvae and the third from a Platydracus (I’m guessing violaceous since I found it under bark).

Philonthus pre-pupa in a  chamber found under bark in early spring.

Philonthus pre-pupa in its chamber found under bark in early spring.

An Exallonyx larva emerges from the Philonthus pre-pupa.

An Exallonyx larva emerges from the Philonthus pre-pupa.

Exallonyx ready to emerge.

Exallonyx ready to emerge.

Exallonyx sp. 1

Exallonyx sp. 1

Collected 3 individuals from their own subcorticular Philonthus during a field trip to McLean Bogs for a class on insect larvae.

Another Philontus parasitizing Exallonyx sp. larva, exiting its host.

Another Philonthus parasitizing Exallonyx sp. larva, exiting its host.

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Exallonyx sp. 2 pupates, leaving the Philonthus larva a husk.

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Exallonyx sp. 2 pupa begins to darken.

sp. 2

Exallonyx sp. 2

A second species of Exallonyx from another Philonthus at Six Mile Creek, Ithaca, my old hunting ground.

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A closeup of Exallonyx sp. 3 reveals the larva’s minute mandibles and a vague eye spot.

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All in a row, Exallonyx sp. 3 pupae.

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Exallonyx sp. 3

I think this is Platydracus violaceous, the larva was under bark at Six Mile Creek. Unlike Philonthus, this large larva can house multiple individuals of Exallonyx. The larvae all emerge synchronously and orient themselves in the same manner, most notable once they have pupated.

In 2007, I was also able to rear out a Brachonidae from Sepedophilous to pupation, but the adult never successfully emerged. This was unfortunate, since this would have been the first documentation of Brachonidae parasitizing a staphylinid.