Category Archives: Collecting

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.

Cryptic species complex in a North American Deinopsis species.

Sometimes it can be tricky deciphering the difference between intra- and inter-specific variation – differences between individuals of a given species as opposed to those that exist between representatives of different species – without consulting molecular divergence. When molecular data is lacking, taxonomists typically compare a large sampling of individuals across the available morphological variability in order to identifying species boundaries; taxonomists typically look for breaks in a seeming continuum of morphological variation.

In the case of the genus Deinopsis, there was a noticeable lack of available specimens for this sort of approach when the genus was revised in 1979. Understandable given the scarcity of Deinopsis, they seem to be a rare group.

Genitalic variation in Deinopsis harringtoni, illustrated by Klimaszewski in his revision of the genus.

Genitalic variation in Deinopsis harringtoni, illustrated by Klimaszewski’s transformative revision of the genus.

In Klimaszewski’s comprehensive revision of the genus, genitalic vatiation (a feature commonly used to distinguish species) in Deinopsis harringtoni, a rather widespread northeastern North American species, was determined to represent intra-specific variation.

Deinopsis species occur in swampy and more muddy banks of slow to stagnant bodies of water compared to Gymnusa, a related genus that I previously introduced how to collect. Incidentally, I had the opportunity to collect Deinopsis on several occasion last summer.

Exemplar Deinopsis habitat.

Exemplar Deinopsis habitat from Vermont.

Among the Deinopsis specimens I collected were two series which I had tentatively identified as D. harringtoni, but males from the two samples sported different genitalic morpho-types. Considering the possibility that this genitalic variation in fact represented species boundaries, I sequenced both D. harringtoni samples to compare their pairwise molecular divergence.

Modified by CombineZPModified by CombineZP

Low and behold, comparing partial COI sequences of the tentative D. harringtoni specimens in reference to a Palearctic species, D. erosa demonstrated over 20% sequence divergence between every pairwise comparison of the three Deinopsis specimens. The morphological differences between D. erosa and harringtoni qualitatively appear significant, suggesting that the degree of molecular divergence I found in the partical COI sequences sufficiently identifies species boundaries.

What was previously considered intra-specific variation in D. harringtoni genitalic morphology may in fact indicate boundaries between species that: geographically occupy close to overlapping ranges with little to no external morphological identifiers – Deinopsis harringtoni could be a complex of cryptic species. Pretty exciting stuff and definitely warrants more collections to be made across the country to sample more populations. This will be fun and challenging since these guys can be pretty rare.

Deinopsis spp sequences Mesquite

These are larval Baeocera scaphidiines. The adults are super un-rove-beetle-like.

Baeocera larvae weave in and out the hymenial surface of polypore fungi.

Baeocera larvae weave in and out the hymenial surface of polypore fungi.

Bass are spawning, so I went to check out the fishing over at WCP for 2 hours. The fish were small but active. Even picked up a bluegill with a larger top-water minnow. 3 l.m.bass, max of 12 inches, and 1 blue-G.

Today’s lures were:

Rebel Pop-R, an unstoppable top-water lure. The fact that you can see the bass attacking from below, visually, is amazing.

Rapala Original Floating, something someone picked up for me at a garage sale. The Original is a pricey lure and I was hoping to reek the benefits of tradition. In fact, picked up most of the fish off this baby today. Was using a darker natural color on a cloudy day, I’ve gotta get some brighter colors.

Soil washing and Mayetia

Our collection manager Zack and I have been talking about soil washing in Kansas for some time now. Soil washing, for those of you who don’t know, is a technique used to collect insects (in my case) that are subterranean.

In staphylinids, two lineages, Leptotyphlinae and Mayetiini (Pselaphinae) are exceptional in having taken this lifestyle to its extreme and have appreciably diversified in doing so. The two are surprisingly convergent in morphology, although they occupy disparate regions of the rove beetle tree of life.

Zack had heard a rumor that a leptotyphline, one of these subterranean staphylinids, had been collected from a root-ball in a Kansas prairie. Rumor passes down to me, and this rumor was what fueled our motivation to put into action, what is arguably the most tedious method of collecting.

Step 1. You dig. I don’t know, pick a spot, any spot. We chose a variety.

Me, digging for, well… soil, out in Kansas prairie. Photo courtesy of Zack.

Step 2. For this step, you literally wash the soil. I dumped the soil etc. into trash bin and added water with a hose. After a reasonable amount of water had covered the soil underneath, I sloshed the soil around and skimmed off anything that floated to the surface (this is all organic material, including bugs).

Wash'n some soil.

Washing some soil.

Step 3. I then wrapped any organic material I skimmed from the surface of the water into a bundle, using cheesecloth. I then wrung out this organic bundle of any excess water, wrapped it again, this time in paper towels to further dehydrate, and stored them in labeled baggies until Berlese time.

A bundle of organic stuff. The samples can be stored like this for about a week. So you can transport them back from the field if you're far from home.

A bundle of organic stuff. The samples can be stored like this for about a week, so you can transport them back from the field if you’re far from home.

Step 4. Berlese time. It only took about a day, the stuff wasn’t very dense.

Berlese!

Berlese! A little makeshift spot for this particular project.

Step 5. Sort.

Mayetia peasei are easily packed into a 1 cm square.

Mayetia peasei are easily packed into a 1 cm square.

To some extent, I think I speak for both Zack and I when I say we had low expectations. This added to our surprise when we found close to 20 individuals of a teeny-teeny staphylinid. We go back and forth for some time about whether it was a leptotyphline or Mayetia, finally settling on the later – I mean they’re so damn convergent-looking!

A little more digging around lead to a species identification, Mayetia pearsei. This species is presumably parthenogenic, argued from the fact that not a single male has been discovered, despite some serious effort. Other species in the genus are known to demonstrate extremely female-biased sex ratios.

Mayetia populations aren’t very dense and individuals are poor dispersers. If chances of meeting a mate are unlikely, this can fuel the establishment of parthenogenesis in a population. In some species where males are present in low frequency, they may play a dwindling role as a population marches on towards purely parthenogenic reproduction. Also possible, males are retained for periodic out-crossing, which theoretically can help avoid pitfalls like Muller’s ratchet and environmental instability. Whatever the case, it seems clear to me that this is an interesting system that deserves more attention; several obvious questions and solutions immediately pop in mind.

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?

First termitophile of 2013

I checked out the weather Friday evening and Saturday was forecast to be excellent weather, in the high 70s. Couldn’t resist, I woke up at 5 AM on Saturday and headed 2 hours south of Lawrence to a favorite inquiline spot.

I’ve introduced some collecting from here previously.

It was a little early still in the season, but the social insects were out and so were their guests. This time I brought home the Philotermes species that occurs here along with its hosts and observed its behavior. Conclusion, a damn lot of grooming.

Philotermes sp. in typical abdomen-over-body look.

Philotermes sp. in typical abdomen-over-body look.

A worker termite checks out Philotermes.

A worker termite checks out Philotermes.