Wednesday, September 2, 2015

Chemical messages of Soft-winged Flower Beetles are still not understood

Collops quadrimaculatus
 Our Mesquite trees are blooming for the second time this year. Among the insects drawn to nectar and pollen are colorful little Melyrids (Soft-winged Flower Beetles) probably of the species Collops quadrimaculatus. The whole genus is in need of revision, so who knows.
The larvae of Melyrids are predatory. Several species live under bark and prey on wood boring insects. Adults feed on pollen, nectar, but also other insects or their eggs.

Collops bipunctatus feeding on moth that a crab spider dropped
 I've even seen Collops grab prey from crab spiders, and I often find them lurking around the webs of cribellate spiders.
 These observation raise the question how these soft little guys can dare to be so bold?
Vivid aposematic (warning) colors seem to indicate that they are distasteful or even toxic.

Collops bipuntatus specimen with protruding vesicles photo Sam Droege

In addition, when disturbed the beetles can protrude red vesicles from the sides of prothorax and basal abdominal segments. But so far, attempts have failed to show that  predator deterrents are either on those pouches or are released from them. 


Now to some friendlier aspects of chemical signals: In males of the genus Collops several basal antenomeres are greatly enlarged. I have watched a male approach a female and present his vibrating antennae for her inspection, touching them to her antennae and sweeping the knobs across her head and pronotum. It looked as if he was maybe releasing pheromones towards the chemoreceptors on her antennae. Some literature suggests that he might release a substance that she would lick - which would make her receptive to his advances. In the case that I watched, she was not interested. He kept waving his antennae at her very persistently, but she eventually walked off. So my observation does not allow to decide whether he presents just pheromone communication or offers gifts and treats.  

Friday, August 28, 2015

Parasitism and Symbiosis


Thousands of Hippodamia convergens converge on mountaintops 
In summer in the mountains of AZ, we often see huge congregations of Lady Beetles. They may migrate up to higher elevations to escape the oppressive heat in the valleys.
In the mountain meadows around Flagstaff, a little parasitic wasp is ready for them: Dinocampus coccinellae, a braconid wasp, stings a ladybug to oviposit. The wasp's larva then develops feeding on the beetle's heamolymph. Also transferred is a virus: D. coccinellae paralysis virus (DcPV for short). The virus multiplies in the developing wasp larva and eventually infects the ladybug's nervous system. At the time the wasp hatches and pupates, the virus immobilizes the ladybug. The brightly aposematic and toxic beetle is forced to stand guard over the silk cocoon that its former unwelcome guest has spun beneath it, basically providing protection for the pupa. The beetle is still able to move, but not to walk away. The DcP virus may actually enhance the deterrent effect by making the beetle twitch. In a recent study, no wasps without virus were found, so there was no test group to see what happens if the wasp pupa has to develop without its protector. Surprisingly, researchers did find that a fair percentage of beetles actually makes a full recovery. Who would have thought? It is not clear though if those recovered beetles are still able to reproduce. And would the be possible hosts to the same sp. of wasp again? Would they be immune to the virus the second time around?


The wasp cocoon in my photo was already empty, and the beetle looked quite healthy, if still tethered. Ready to go, actually. I found it and several others on a mountain meadow near Snow Bowl, Coconino Co. AZ  8/5/2015'

Original research by The topic was recently also treated by Eric Eaton in his blog and by National Geographic' website.

Monday, August 24, 2015

Butterflies at Proctor Road

Jeff in action, here shooting an owlfly, not the hister on the right, that's something that happens later at the U of Madison, WI

 On Saturday morning (8/22/2015) I met with Jeff Gruber at Proctor Road, Madera Canyon to go bug hunting. Jeff is the most excellent macro photographer whose virtual insect collection  on BugGuide years ago gave me the first glimpse into the possibilities of stack montage photography. He was searching for myrmecophile beetles (beetles that live in ant nests).


A nest full of friendly ants and my attacker - the Pogonomyrmex whom we were not bothering at all
Because this involves the slightly Sisyphean job of turning rocks of the size one just about cannot manage, we started earlier than usual for insect observations. At the first nest  Jeff found a tiny (around 1 mm) hister (?). I leaned in to get some shots of workers and pupae for my impending talk about ants at the Senior Academy.  
While the ants who had the roof lifted off their nest were quite peaceful and never bothered Jeff, three members of a neighboring Pogonomyrmex colony  climbed up inside my wide cargo pants and nailed me. Outch! I was wide awake after that.


In grasses and shrubbery, night active neuropterans were hanging out for the day. There was one Owlfly,  but most were anlions (I hope their larvae will get a lot of Pogos!) that lined up along Sotol leaves and blades of grass. There, they all moved around in unison, trying to hide behind their narrow perches. 



This behavior made photography difficult but did not deter hunting jumping spiders in the genus Phidippus.     




Along Madera Creek and Proctor Roads, Robber Flies seemed to be even more prevalent than usual. Most of them perched at the ends of twigs surveying the area for prey. The ones that were already  feasting all had beetles for breakfast: so that's why I could hardly find any.


The notable exception were leaf beetles of the species Leptinotarsa haldemani on a completely leafless Wolfberry bush and Zygogramma signatipennis whose larvae had shredded the leaves of Tithonia thurberi until only fine lacework was left. 


Still, the asteraceae were in full bloom and attracted scores of butterflies. We are both no lep people, but the amazing sight was not lost on us. A local butterfly hobbyist stopped by because he saw our nets: within minutes he yelled back that he had seen 28 species, including  Microtia elva (Elf ) that he was trying to breed. 

video

Luckily I had documented the tranquil scene before he showed up - just the creek rushing, Gray Hawk fledglings calling, and dozens or hundreds of butterflies dancing among the flowers in the dappled shade of hackberries, junipers and oaks. For better quality, please watch the video through this link


Eventually around 2 pm the thunderstorms forced us back to our cars. I drove home via Mission Road through the reservation and found myself in the aftermath of a downpour where the road was covered in sand, rocks and other debris. 
The radio program was constantly interrupted by 'damaging wind and hail' warnings and on the intersection of Ajo and Mission it felt like a load of rocks was pelting the car. But I escaped westward into bright sunshine and watched the dark wall rushing behind me towards Tucson.

   

Thursday, August 20, 2015

Bug Safari 2015 - Northern Arizona

I've been so busy lately that this blog was neglected. Lots of reasons. At least half a dozen public talks about our insect fauna needed to be prepared and presented. This is also the main season to collect bugs for breeders and scientists, so hundreds of ants and beetles had to be packed, shipped, declared ... Parties for entomologists like Pat Sullivan's Infestation came and went. An exciting new project with Art Evans involving my beetle photos is taking shape.

Navajo Horses. watercolor from an earlier trip north
But most of all, I got to spend several days in the field with a few of my best naturalist/entomologist friends. Robyn Waayers came from San Diego County,  Alice Abela and Aaron Shusteff all the way from northern CA.

Oak Creek Canyon, West Fork, Sedona, AZ
We all are very fascinated with the wonders of SE Arizona and we all had been there several (or many in my case) times. So this year, we headed to northern Arizona instead, knowing that the species and individual numbers of insects might be lower there, but all of us would find something new and probably unexpected. Luckily, Derek Uhey, a resident researcher of the NAU Forestry Department, invited us to join him at some of the research sites he knows so well.

Mydas xanthopterus
After settling in at Clear Creek Campground in the Verde Valley, our first excursion took us through terribly touristy and congested Sedona to Oak Creek Canyon's West Fork trail head. I have described the beauty of this area in another blog. This time, we did not get very far because our progress is slow: we turn over over just about every leaf along the path, check behind most sand corns, definitely look at every flower.

Eastern Box-elder Bugs, Lixus semivittatus, Asclera ruficollis (Red-necked False Blister Beetle), Paraphidippus aurantius, Bombus hunti
 Also, it was late in the day, especially for a shady canyon. But besides watching some crepuscular beetles, we soon discovered that sleeping bumble bees have a lot of charm and offer many photo ops. Hard to believe that Alice and I still found time to stuff ourselves with delicious black berries!  Aaron and Robyn indulged in a bath in Poison Ivy instead, but since nobody came down with any symptoms, our botanical knowledge seems to be lacking?


Black lighting at Clear Creek Campground attracted  mostly old acquaintances from southern Arizona. This also turned out to be our last night with temperatures warm enough to bring in multitudes of insects, the moth Eudesmia arida being the dominant species.

Derek, our local expert with his (or Hayduke's?) trusty blue Jeep. Photo by Robyn Waayers, another Abbey fan

Zygogramma continua, Collops bipunctatus (Two-spotted Melyrid), Megaphorus sp., Arethaea (Thread-legged Katydid)
In the Flagstaff area we followed Derek to one of NAU's garden arrays in a formerly heavily grazed, lava rock-rich habitat.  Garden arrays are fenced, controlled test sites where the progress of original vegetation and also of planted trees under the influence of the changing climate is monitored. Insect studies are mainly performed by pit trapping (Derek's amazingly demanding project), so with swipe net, cameras and simply gleaning we may have added a few species to the lists.

Next we headed towards the San Francisco Peaks, to a research site below Snow Bowl Ski resort.  A disturbed area along the road was covered in blooming thistles and made us curious enough to stop.

Bombus morrisoni (photo Derek Uhey)
 Were they native? Was this a field to grow bird seeds? We did not find out. Like most monoculture sites, this one did not offer too much of interest, but the bumble bees were of amazing size.

San Francisco Peaks, Arizona' highest
We then drove through miles of pine forest to our target site within a nature preserve. A beautiful mountain meadow surrounded by aspen and pines was rich in blooming yellow Sneeze Weed that was past its prime but still attractive to many interesting flies and bumble bees.

Chaetorellia sp., Xanthoepalpus bicolor, other tachinid, bumble bees
We camped outside the preserve at the border between open meadows and pine forest. While we set up camp, Common Night Hawks entertained us with loud nasal shrieks that I had never heard before. Then it got cold. We brought out all our warm clothes and feared that no insects would show.

Trichocnemis spiculatus neomexicanus          Alice, Aaron and me (Photo Robyn)                       Tragosoma harrisii
Alice, undiscouraged, laid endless trails of cereal. To me, she seemed to turn into a fairy tale character, and darkling and ground beetles as well as many camel crickets soon fell for her magic.

Catocala grotiana ,Pseudohemihyalea ambigua, Estigmene albida, Hypercompe permaculata (Many-spotted Tiger Moth) Bertholdia trigona (Grote's Bertholdia), Lophocampa ingens, Grammia williamsii
But our lights also were successful despite the low temps. I guess bugs that live up in the Flag area are used to the cold. From the coniferous forest we drew some large Cerambycids. Moths in the family Eribidae which now includes the Tiger Moths added a lot of color. I saw my first Pandora Moth.

At Navajo Bridge
The next morning we made our way towards the North Rim of the Grand Canyon. We drove through some of the most amazing red rock and badland country of the Navajo Reservation without stopping or photographing. Did I mention that our lead driver had just been on a trip through Utah's Canyon Lands and got oversaturated with that kind of beauty?  We also thought that on the way back ....

Nankoweep
This week our newspaper reported record tourist crowds that choked traffic at the South Rim of the Grand Canyon. We saw none of that. With the famous cookie shop inn in Jacob Lake, we left all of it behind. The mixed conifer forest was majestic the dirt roads were empty. At Nankoweep, our first choice camp site right on the rim was taken, but with three tents plus Derek's hammock  we were better off some 50 m from the rim anyway. Promising wild flowers, fallen trees with loose bark, thickets of raspberry bushes - the site was ideal and seemed very rich. But rather soon, dramatic storm clouds were rolling through the canyon, obscuring parts of the incredible view. Derek, experienced with the land, pointed north, away from the Canyon: those clouds were coming right at us. We put up lights at protected spots among Aspen and Alice laid her cereal trail.

If Alice had not forgotten to bring the white table cloth, her cereal buffet would have looked like this
We got little, but what came was good. Before turning in for the night we still had to move Robyn's and my big coolers, full of of food and bugs, from Robyn's canvas-top truck into Alice's sturdier vehicle - it's bear country after all. Derek sang us to sleep accompanied by Aaron's tiny traveling guitar. During the howling storm and pelting rain of the night, poor Derek in his hammock did not get a lot of rest and no bear ventured out.

Canyon view in the morning
 In the morning Derek had to visit his research sites in the area but we did not, as planned, accompany him; the weather was just too bad. So we looked longingly through our truck windows at beautiful wildflowers nodding with dripping wetness and searched  the road in front of us for salamanders - shouldn't they, at least, be out and about in this weather? Very impressive lightning strikes close by. Robyn raised the question if it's really safe in a car? I chose to firmly believe in Faraday's cage right then and there.


Charlie Brown Blister Beetle and Pandora Moth
We stopped for breakfast at Jacob Lake and found the outside walls covered in Pandora Moths and a few good beetles - those had come to the lights of the gas station at night. Definitely a spot to spend some more time, next time.

I wanted to look for Sage (Artemisia sp.) specialists on the way back, but again, the rain got us as soon as we left the cars.

 Beautiful red rocks shrouded by rain, no photo stops possible on this leg of the trip.

At the Little Colorado River: next to the water the sandy area where the tiger beetles would be.  Between Aaron and the cliff dead and dying Tamarisk trees all along the river
Aaron knew about a rare Tiger Beetle on the banks of the Little Colorado River. No access at Navajo Bridge, but more luck at Cameron. We did not get the Tiger (who was probably hiding from howling wind and pelting rain). But we were hardly out of the trucks when Robyn pointed: 'Weren't you looking for those bio-control leaf beetles that kill tamarisk?

Diorhabda carinulata (Northern Tamarisk Beetle)
 That tree does not look too good!' The tree turned out to be literally covered in beetles. As I described in one of my first blogs,  Tamarisk is an introduced, invasive tree that displaces many riparian plant communities. Efforts to fight it with beetles and scale insects introduced from its countries of origin have proven to be successful in Colorado and Utah. In AZ the release of the 'agents' was not allowed: The birding community feared for the protected Willow Flycatcher that had switched in some areas to breeding in Tamarisk. Some Tamarisk thickets also offer resting places to large concentrations of migrating birds, and birders do not want to loose those great observation opportunities. Another argument was that mature, established Tamarisk thickets would have made the soil permanently unsuitable for willows and other pioneers due to salt accumulation. The question arises of course if it is better then to let the invasive trees spread unchecked? So no leaf beetle release in AZ. Well, the bugs do not respect state borders - they are here. And they are chewing up Tamarisk. Being established in flood planes and riparian corridors, they will probably spread throughout the state pretty quickly. Lets hope that the results are catastrophic only for the invasive Tamarisk.


Going through Flagstaff, we encountered down-poors so strong that the windshield wipers threatened to give up.  And no silver lining anywhere, just more heavy clouds and lightning. So we kept going south, to Prescott. That way, we missed our planned visit to the insect collection of the NAU and did not see Derek again for now. Too bad,we had very much looked forward to both.


In Prescott, the sky finally cleared. We black lighted at Watson Lake Campground, but found that the tall, bright lights of the park drew the larger scarabs. A nice big male Strategus aloeus crash landed right next to the bath room (hot showers!). There was still enough of a light show to inspire Robyn to try and photograph lightning bolts instead of yet more beetles.

Leptinotarsa rubiginosa (Reddish Potato Beetle)
Alice found a Reddish Potato Beetle, one of the two species that I still needed for Sean Shoville's research project which includes all 7 AZ Leptinotarsa species. In the morning we explored the banks of Watson Lake and Granite Creek first from the campground side, then from the path through the Granite Creek Nature Preserve.

photographing bugs at Watson Lake (photo Robyn Waayers)
 I know the area very well, but it always has something new and interesting to offer. For example, I had never found Euphoria inda anywhere except in Portal, in the very SE corner of AZ. Now we found 2 of them, and just like the one in Portal, they were clinging to narrow-leaf milkweed flowers.

Cicindela obsoleta santaclarae
Beautiful, very large Tiger Beetles Cicindela obsoleta santaclarae appeared on vegetation free patches along the lake, and a smaller, also emerald-green ones, kept getting away from my lens. Finally the heat (!) wore us out and over a nice Mexican lunch we said good bye until we can hopefully do something like this again.

Nemognatha sp. with eggs, Apiomeris flaviventris, Batyle ignicollis oblonga, Neoalbertia constans, Euphoria indaPepsis mildei
Since I'm back in southern Arizona, Derek, who is not only an extremely hard working field biologist but also a remarkable artist with his camera, keeps tantalizing me with the most beautiful landscape and night-sky-scape photos from up north, and I feel a great urge to load my van to drive back up. Lets see how long I can resist.    
 
Night sky over the badlands by Derek Uhey

Wednesday, August 12, 2015

Swarming Leaf-cutter Ants

Last night we finally had a very heavy rain storm here in Picture Rocks on the NW side of Tucson. The rain came in in horizontal sheets, lighting flashed while simultaneously thunder clattered, tree branches flew, washes rushed and Spade Foots bleated. This morning then, volcanoes erupted.


Columns of moving particles rose into the air, hovering up and down over the tops of trees and my head. Leaf-cutting Ants  Acromyrmex versicolor  celebrating their nuptials.


 Winged males and females had been waiting for their chance in the depth of the colony and were now pushed into action by busy workers. They did not actually poor out of the volcano but out of another exit of the wide-stretched underground city.


During their aerial dance, males and females found each other, began to mate and tumbled to the ground, the pair often imbedded in a cluster of less lucky males. The small headed males die shortly after mating.
   


The young queens are easily recognizable by their big, well formed heads. They do not only carry a piece of the old colony's fungus (the only food this species enjoys) in their crops, they also have the mandibles and muscles to start cutting leaves and begin a new fungus garden. Until the first workers are born, all the work is done by these young queens. They often gang together in small groups to get started, but the dominant queen may later eliminate her sisters. 


Colonies of this species are huge under-ground cities with many chambers. They are always located in the vicinity of trees, not out in the open. I have watched the mother colony in front of our house for 13 years now. The 'volcanoes' vary in size and location, activity levels around the entrances go up and down, but the colony survives. The swarms appear after a heavy rain fall, sometimes as late as October. All colonies in the neighborhood are active at the same time. But they are so far apart, and the swarms so stationary - exchange between them seems rather unlikely. So are the ants constantly inbreeding?

Entomologists thought that the devoted altruism among colony members is based on the fact that all of the workers are full-sisters, sharing 75% of their genes. Doubts came up when it was discovered that the queens mate with several males, so their offspring might share only 25% of their genes. But if all those males are really just brothers of the queens from the same colony, the off-spring would be related to a much higher degree and altruistic, self-sacrificing behavior would be much more understandable - in the end it's the egoistic gene (-nom) not the egoistic individual.