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Monday, January 26, 2015

All about Mantids

This blog is the sum of my contributions to our SW Insect group on Facebook for the week-long theme 'Mantodea'
As usual, we looked at species diversity, biological cycle, physiology, behavior, and popular myths. 


One story that is NOT  a myth to be debunked: Female Mantids tend to bite their mates heads off. Obviously, it's not the rule as this happy couple demonstrates, but it does happen quite often. Research has shown that decapitation in no way interferes with the successful completion of the mating. Actually, it showed that the headless males were more eager than ever. Making the most of their last chance ..


With his permission, I am posting this great photo by Amit Mahajan, Mumbai, India, August 2014 because I cannot find mine of an ovipositing Manits.
He writes: When the female mantis is ready to lay eggs, a protective covering called "ootheca" will be extruded and this will serve as the housing of the eggs. The eggs will then be deposited into the folds of this ootheca.
The shape of the one produced here is similar to that of a Chinese Mantis. That species is sold by and for gardeners for biocontrol. Please do not buy (release) them. They will interfere with the balance of our natural system that already has a number of Mantids that are superbly adapted to the Southwest. So far I have not found any Chinese Mantis in Arizona, but Iris oratoria, a European import can be found.


The oothecae of mantids are species specific in shape, coloration (?) and probably size. Here are a few, Stagmomantis sp. are the most commonly seen ones in Arizona. Ground Mantids, Litaneutria minor should also be common, but I don't know where and for what to look. Top right and bottom left may both be Iris oratoria, but I'm not sure. The Pseudovates arizonae ootheca, bottom right, is cropped from Tony Palmer's excellent shot that he posted a while ago on FB


 Stagmomantis ootheca with hatching nymphs. Mantids are hemimetabolic insects. The nymphs will go through several molts while growing up, but the basic shape will not change. Stages of nymph between molts = instars. Wing buds will be apparent in the late instars. There is no pupation in hemimetabolic development. The adults will have sexual organs and, in this species, wings. After that stage is reached, there will be no further growth or molt.

Podagrion sp. male
Most oothecas of mantids have little round holes. These are not the exit holes of the mantid nymphs - the nymphs emerge through the gaps in the zipper-like structure that the mother has built into the egg mass cover. But like most large accumulations of eggs and embryos, the ootheca attracts parasites, mostly little specialized Chalcidoidea (Chalcid Wasps) in the genus Podagrion.


Arizona Unicorn Mantis nymph molting between instars 4 and 5: this is the last molt before adulthood and  the 4 budding green wings are recognizable


Adult Arizona Unicorn just after her last molt, winged and ready to find a mate.

Ground Mantids, Litaneutria minor, winged male
Picture Rocks, Pima County, AZ, USA, 5-20-2014
The males of this little mantis are very common at porch lights around our house. The females are flightless and seen more rarely.


Yersiniops sophronicum (Yersin's ground mantis)
Brown Canyon, Buenos Aires Preserve, Pima Co, AZ, September


Stagmomantis limbata female, French Joe Canyon
Cochise County, AZ
Here is my favorite mantis photo:
  Raptorial arms and binocular vision make them formidable predators.
Mantids are characterized by binocular vision and the ability to move their heads relative to the rest of the body. This feature that endears them to many human observers is of course vitally important to a hunter who needs to judge whether prey is within striking distance.

Male Stagmomantis with light-adapted compound eyes above and dark adapted eyes below.
 As visually oriented predators that are day and night active, Mantids also have eyes that function well under extreme lighting conditions.


Their eyes, like most insect eyes, are compound aggregations of multiple vision-units, Ommatidia, that each consist of a lens, a cristalline cone and a receptor cell. These units are isolated from each other by pigment in pigment cells, allowing for focused, separate light reception of each unit.
In species that, like Mantids, are both, day and night active, the pigment enclosed cylinder tends to be especially long. You can see the clean separation of the ommatidia - a small, dark pseudopupilla seems to stare at you from the otherwise light-colored eye. The pseudopupilla is formed by those ommatidia whose angle is such as to allow you to look all the way down through the pigment enclosed cylinder into the depth of the eye. The light areas of the eye are ommatidia that don't look directly at you, so all you see is the reflection form their pigment cells.
But at night, the same mantis eye is dark all over and has no clear pseudopupilla. What happened? Most of the pigment in the pigment cells has moved towards the center of the eye, leaving the outer part of the ommatidium without focusing shield, but open to more incoming light. The reception is less clear this way, but brighter. The same principles that work on our own dark-dilated eye are at work.

Sunday, January 18, 2015

Camouflage and Hiding in plain sight

Most insects are small and delicious. So their constant problem is how not to be eaten. In our SW Facebook group we already explored aposematic colors in this context. This week it's the opposite strategy: Hiding from predators. We won't be purists. I will include insects that pretend to be parts of plants or other natural structures, even if those are sticking out like thorns. Some people may want to call that mimicry, but I will include them here. 

Platycentrus acuticornis Montezuma Wells, Yavapai County, Arizona, USA
May 30, 2010...

Enchenopa sp. (undescribed)
Florida Canyon, Pima County, Arizona, USA
November 19, 2010
If a bug 'pretends to be' a thorn among thorns, is that mimicry or camouflage? Anyway, a number of Membracidae (Treehoppers) avoids predation that way.

Santa Rita Lichen Grasshopper, Leuronotina ritensis, Ruby Rd, AZ
This is Bob Behrstock's photo that he allowed me to use for the d_UAIC on flickr, so I guess this use here is fair.
Anyway, all observations I know of are from AZ, so I'd be curious to see any from other areas - Sonora Mexico probably has them, too....
The grasshoppers seem to be confined to rocks with those specific encrusting lichens, so I assume they also feed on them,
By the way, the hind wings are bright orange


Sphingicampa montana (Syssphinx)

By themselves, and illuminated by flash at night the caterpillars of our small silk moths, the Sphingicampa (Syssphinx) species, seem outrageously colorful and showy. the little slivers on the back are actually reflective like mirrors, reminding of sparkling Turkish dancing dresses.
All of them live in leguminous trees or bushes with leaves broken down into little leaflets, like mimosa and mesquite. I had no good daytime photo (I borrowed this one from Ken Cave)... I usually don't see the caterpillars during the day because they are so well camouflaged. All the white markings and even more so the reflective bits break down the shape of the big caterpillar among those tiny leaflets, even seen against the light. You will find white or silver markings on almost all insects that live among Mesquite leaves, Creosote leaves, and Tamarix and Juniper twigs. There are stink bugs, geometrid caterpillars, leaf hoppers, katydids, grasshoppers - I'd even count the silver striped Glorious Scarab here (it feeds on juniper)

Synchlora frondaria, a green geometrid
on Acacia,  Molino Basin, Pima Co, AZ June,
 David L. Wagner says, "A Mardi Gras caterpillar that is out of costume only after a molt. The larva fashions its disguise by attaching plant bits (usually flower petals which it has chewed free of its food plant) to its back.


Mecaphesa (?) sp. and Misumenoides formosipes (middle and right) from AZ desert and sky islands
Many ambush predators have evolved to be masters of camouflage. This one is especially impressive:
"Crab Spiders in the genus Misumenoides formosipes are a sit-and-wait predators that do not use a web for prey capture. Instead, they sit perched atop flowers with their front pairs of legs spread open wide in preparation for capturing whatever unlucky insect comes near. These spiders are actually capable of actively changing their body color from yellow to white, or vice versa, depending on the flower they are perched on. They do this by transferring a liquid, pigmented material to the cuticle. The color change is not instantaneous; it can take anywhere from three to nine days to complete (G. N. Dodson, personal communication, June 2014)." Adapted from http://www.spiders.us/species/misumenoides-formosipes/
Hamataliwa grisea, a Lynx Spider. Molino Basin, Pima County
Good camouflage requires more than just the right colors or textures. Behavior is a big factor, too. First of all, the bug has to stay on the surface it is adapted to. Then it has to sit still. But there remains the problem of the cast shadow, as illustrated in the toad bugs that had more important things in mind. This spider gets it right, though. The legs are pulled towards the body to form one inconspicuous, continuous shape. Bristles form a soft connection without overhangs or abrupt angles to the surface it is sitting on. The result: No sharp cast shadow.
Hamataliwa grisea, a Lynx Spider. Molino Basin, Pima County

Tetragnatha (Longjawed Orbweaver) Santa Cruz River bank,Marana
Pima Co AZ,
The problem with macro photographs for this topic is that we usually blow the bug's cover when we have finally found him. Imagine this Tetragnatha (Longjawed Orbweaver) in a tangle of twigs and grasses : she'd be quite hard to spot.
These spiders are often close to water where they spin circular (orb) webs, mostly in the horizontal plane, often just inches above the surface of water where they can intercept emerging insects like midges, mayflies, and stoneflies.

Arizona Unicorn Mantis Nymph (Pseudovates Arizonae)
Molino Basin, Catalina Mts, Pima Co, AZ
This girl was already big, over 2 inches, when I found her and molted twice before becoming a green-winged adult. The nymph seems more cryptic than the adult, but I must admit that I personally have found several nymphs (I raised this one) an no grown-up ever. The nymph has all the right patterns, colors and the shape to blend in with dry branches. It also moves in slow motion and hides its directed movement towards prey by simultaneously swaying from side to side as if the whole motion was wind induced. I'd call that camouflage of intent..

Gratiana pallidula (Eggplant Tortoise beetle)
Many Leaf Beetles (chrysomelidae) are toxic and announce that fact with warning colors, but a good number survives by being cryptic - larva to adult. Tortoise beetles have successfully eliminated the cast-shadow problem. The seamless contour with the surface is combined in some species with extreme strength holding the beetle to that surface - nearly impossible for ants to grasp or dislodge.
Gratiana pallidula (Eggplant Tortoise beetle)
can be found on several solanaceae

Gerstaeckeria sp. on Cholla, Blue Sky Rd, Willcox, Cochise Co. AZ

Cactus weevils in the genus Gerstaeckeria are hiding by lining up with the tufts of glochids in the areoles of a cholla cactus. The weevils are night active and come out at dusk when they blend in with those structures of the cactus surface even better. Experienced entomologists like Charlie O'Brien are not fooled. They look for tell-tale little circular feeding marks rather than for the weevils themselves. So right now, Charlie is describing a new species of the genus that lives exclusively in one of the rare and protected pineapple cacti. Obviously, the bugs are oblivious of the endangered species laws. On the other hand, that weevil is probably more endangered than its host.

Gelastocoris oculatus, Big-Eyed Toad Bugs.
 These pea-sized True Bugs live along muddy freshwater shorelines and are often overlooked. Their locomotion is described as walking, sometimes hopping. When we had 'hopping' as a weekly theme, I could not find any Heteroptera that hop - well, here is one. If that makes them look (if you see them at all) even more like baby toads, I don't think that would be a great mimicry protection, because those, too, get eaten. I think toad bugs and baby toads are both profiting from being nearly invisible. But: Motion draws attention. Occasional hops are of shorter duration than continued crawling along and thus would betray them less - so hopping may be a behavioral aspect of their camouflage.

Schinia miniama Kitt Peak, AZ, March
Some day active noctuids spend their time on spring time asteraceae. They feed, mate and lay their eggs on the flower disks and the caterpillars develop eating the maturing fruits. Some species are colored like the multi colored Indian Blanket and they usually even sit in the right position to fir the pattern. Maybe someone has a photo of that


Chrysoecia thoracica, Lochiel, Cochise County, AZ
 In September I saw a number of 'flowers' that I did not recognize. Then I realized that the 'petals' were actually sleeping noctuid moths. They were all oriented with their wings sticking out, heads towards the center.There were groups of them around many of the flowers (Cosmos parviflorus) When I got very close to photograph this group, 3 got upset and flew away, but you can still see the deception that all five together would have produced.

These were my contributions to this weeks topic of the Facebook Group SW U.S. Insects & Arachnids. While many aspects of camouflage and hiding in plain sight were covered, many more could have been mentioned, or were posted by other members. Robyn Waayers had a particularly nice Bag Worm cocoon.
Amy Jaecker-Jones posted trichoptera larvae masquerading as leaf litter at the bottom of a creek

Saturday, January 3, 2015

Jumping Bugs

Most land insects get around by walking and many by flying. Active flying is usually long-distance and more or less direction controlled and it depends on specialized extremities, with aerodynamic structures and powerful, aerobic muscles that need suitable operating temperatures to function (parachuting spiders are a different story).
Many arthropods have an efficient, simpler way of locomotion: they jump or hop. Jumping is often less directional than flying and may be used as a startling, sudden way to escape from danger, even in insects that are able to fly. But flightless arthropods like spiders may also jump in attacks with great precision. To jump, arthropods may employ their specialized hind-legs, usually elongate and muscular, but there are many other structures that are also used – don’t forget click beetles and spring tails ….. So let’s see where this new theme will get us (this was another week's topic for our Facebook group) – and, by the way,  I hope you had a pleasant jump into the New Year 2015!

Lepidocyrtus sp., Slender Springtail
 Springtails (Collembola) are no longer considered insects. But they are Hexapoda (have 6 legs) and (probably) closer to insects than Arachnids which our group does include, and they certainly are 'jumping bugs'.
I had never photographed any, so yesterday I grabbed one of our hedgehog cacti that died last year and shook it over a white basin. sure enough, hundreds of 'slender springtails' fell out. They are too small for my camera but I'm showing a shot anyway.
M...ost species of springtails have an abdominal, tail-like appendage, the furcula, that is folded beneath the body to be used for jumping when the animal is threatened. It is held under tension by a small structure called the retinaculum and when released, snaps against the substrate, flinging the springtail into the air. All of this takes place in as little as 18 milliseconds.




Systena sp. Rock Disk Park, Marana, Pima co, AZ November
Within the beetle family of the Chrysomelidae (Leaf Beetles) is a tribe called Alticini (Flea Beetles). The hind-femur of most beetles in this group is enlarged to accommodate big muscles and they can get away with considerable leaps. Some are metallic, some are striped some have spots, but they are all leaf eaters and rather small.

Acanthoscelidius utahensis, Photo by Won Gun Kim
 There are not many families of beetles that can jump in the traditional sense, using their legs: D.G. Furth and K. Suzuki. 1992. The independent evolution of the metafemoral spring in Coleoptera. Systematic Entomology 17, 341 -349: “The metafemoral spring jumping organ was known previously only from all Alticinae (Chrysomelidae), one genus of Bruchidae, and two species of Rhynchaeninae (Curculionidae).” ""In the Bruchidae the metafemoral spring has been found in one genus Eubaptus. ... The extent to which the metafemoral spring was discovered in the Ceutorhynchinae was unexpected, particularly because only three genera Hypocoeliodes, Aulentes and Acanthoscelidius have been observed to jump." Thank you to Henry Hespenheide for finding the quotation and to Won Gun Kim for the permission to use his weevil photo!


Platycotis vittata (Oak Treehopper)
Molino Basin, Catalina Mts, April
 One of my favorite hoppers. They often occur in big groups, and that must look really spectacular. But I have only found single ones in my beating sheet. Maybe most of them are not easily knocked off their branches. They are wide-spread: much of US and Canada / Mex. to Brazil

Antianthe expansa, Keeled Tree Hopper
on Datura, Sabino Canyon, Pima Co, AZ
December
 Treehoppers (Membracidae) in the order Hemiptera differ from related families in having a large pronotum that extends back over the abdomen and (often) covers the head; many species appear humpbacked or thorn-like; others have spines, horns or keels
Members of the genus Antianthe are subsocial, you'll find maternal egg guarding and ant-attended nymphal aggregations. They, like all hemiptera, are hemimetabolic. This means that they are undergoing an incomplete metamorphosis without a pupal state. Instead they develop over several instars of nymphs. Adults on the left, nymphs on the right.

Scolopsella reticulata, Alphina glauca, Poblicia fuliginosa,
Rhabdocephala brunnea, Acanalonia sp., Poblicia fuliginosa nymph
 
Very typical jumpers are in several families of the order Hemiptera. My collage shows actually members of a superfamily, Fulgoroidae, the Planthoppers. They can look quite bizarre, especially in the tropics, like the alligator look-a-like, the Lantern Bug. Some of our Arizona ones (my picture) also have moderately fancy head gear and some nymphs can produce fluffy waxy tails ... they are all able to hop, they have piercing sucking mouthparts
and are vegetarians (although the story of the biting Lantern Bug will not die....) I like them very much because they are the life-long specialty of my octogenarian close friend Lois O'Brien who just sent me the most hilarious year-end letter about her ongoing research.



Cat Flea
One of the most well known and athletic jumpers, a circus star, but usually very much despised is the flea.
Siphonaptera (Fleas) » Pulicidae are wingless insects with sucking mouth parts and strong jumping legs.
Living with 5 dogs and 2 cats In Arizona, we had one infestation in 12 years. It meant disinfecting all carpets and dog beds repeatedly and washing 8 animals every second day with flea shampoo. We got rid of that pest and afterwards I have only once seen a single flea - strangely on a white surface, not even on an animal. We were expecting the worst again, but no further signs. Arizona's dry climate and sandy soils are not the 'best' conditions for fleas it seems. Constant vigilance and cleaning also keeps any larvae from growing up because they rely on the excrement of adult fleas for food.


Alaus zunianus (Zuni Click Beetle)
Upper Madera Cny, 8/8/2013
 Click Beetles (Elateridae) have no specialized extremities that allow them to jump. Instead, the joint at the union of the prothorax and mesothorax is much more flexible than in most beetles, allowing up-and-down movement of the head/prothorax against the rest of the body. On the underside of that junction, a prosternal spine fits barely into a groove on the mesosternum. Whenever the beetle lies on its back (it often lands like that when threatened and playing dead), it begins to press the thorn against the grove (which has a restricting rim at its entrance), building up potential energy like a coiled spring. When the thorn eventually snaps into the grove, the two jointed body parts perform a sudden movement (click) that catapults the beetle off the ground (hopefully landing right side up) or out of and attackers grasp. If you see one of the large species like this 2 in long Alaus perform the trick, you will agree that this can qualify as jumping.

Bristletail from Peppersauce Canyon, Catalinas, Pima County, Arizona, USA
July 14, 2011
 Microcoryphia (Bristletails)
are 'wingless (insects); body cylindrical, brownish or yellowish with darker mottling or irregular pattern; thorax arched dorsally; tip of abdomen with 1 long medial filament and 2 shorter lateral cerci; long thread-like antennae with many segments; eyes large and meet in middle; mandibles articulate at one point only; short lateral styli (rudimentary appendages) on abdominal segments 2-9; able to jump up to 10 cm by snapping abdomen against ground' quote from Bugguide.net

Salticus palpalis, the Metallic Clown Jumper, Tucson Mountain Park, February
When arthropods are cute enough for the general public to care, they actually have memorable common names! Meet
Salticus palpalis, the Metallic Clown Jumper
Jumping spiders have typically 3 pairs of eyes. The anterior median eyes (the pair of eyes in the center front) are comparatively very large and give these spiders excellent color vision and a high degree of resolution. The shape of the retinae indicates that these eyes function like tele lenses. Obviously they also provide binocular vision, meaning that the spider can judge distances accurately - a must for a jumping predator. The spiders behave like they are more intelligent than other bugs. I think this impression is partly based on the fact that humans and salticids both are very much vision-oriented and thus seem to understand each others reactions quite well.

Cydia latiferreana (Filbertworm Moth)
You are probably surprised to find a moth under this heading. And our Arizona species Cydia latiferreana (Filbertworm Moth) is really no jumper in any way I know of.
BUT:
Its mexican genus-mate is Cydia deshaisiana, the Jumping Bean Moth. The adult moth of that species does not jump either. But the caterpillar does, sort of: It develops in the bean shaped fruit of a shrub (Sebastiania). When the ripened fruit falls to the ground, it may land in an exposed locatio...n where it gets much too hot for the caterpillar inside. So the caterpillar begins to spasm and buck inside the 'bean'. Since the caterpillar has attached itself firmly to the inside of the bean with silken threads, it is able to move the whole fruit, to make it actually jump. So the bean may eventually end up in a micro climate more suited to the needs of the inhabitant. Or not. But what is there to lose if the stimulus for action is sudden overheating?

Friday, January 2, 2015

Photos of the year 2014

In 2014 I developed a fondness for shots with diffuse, non-flash lighting. I also moved away from field guide like documentation of local species to more interesting shots.

Diffuse lighting is especially suited to show the true colors of reflective surfaces, and most beetles are shiny.

I try to get images that show some typical behavior, like this predatory stink bug spearing a leaf beetle on its beak 

This photo has deep emotional value. My beloved Cody followed me on a pre-sunrise search for blooming Queen of the Night Cacti and happened to walk into the picture. It was our the last walk together and the last photo before he died.

Some delicate little insects are still better photographed under controlled studio conditions

I am breeding big scarabs and the larvae get quite enormous. This Dynastes granti still had to grow for at least another year

A shot that took a lot of patients and many failed attempts: a Leaf-cutter Bee is cutting a perfect circle from a Bell Pepper leaf to use as tapestry in her nest

Simply beautiful: the eggs of a Green Lacewing on a Milkweed flower. Practical too: the hatching larvae may feed on the aphids in the background

Also on Milkweed,  Oncopeltus sanguineolentus (Blood-colored Milkweed Bug) a relative of the more common Oncopeltus fasciatus (Large Milkweed Bug)

 Some photos might inspire interesting blog stories, like this little wasp in Ichneumonidae Diplazontinae who's host are aphidophagous Syrphidae

This nest of Polistes aurifer had been exposed when the willows along the Sta Cruz River path were pruned. The wasps were upset and spent a lot of time ventilating the sunniest spots. Late in the year (October), the colony was in decline and maybe because of that the wasps were not at all aggressive. My hand held camera was nearly touching the nest while I shot stills and videos. After hours of observation I could eventually recognize individuals and learned something about their ranks, roles and duties. It was very fascinating.

Thursday, January 1, 2015

Desert Snow 2015



The new year is starting out cold here in Arizona. On the last day of 2014 a storm blew in from the northwest and it rained nearly all day.






On New Year's day we woke up to sunshine and snow on all the mountains around us. So I jumped into the car and headed towards the Sonora Desert Museum that sits just a few hundred feet higher than we in the Tucson Mountains. Before getting there, I turned off Kinney Rd into the Bajada Loop.  This is the backdrop of many John Wayne westerns and the series High Chaparral (much of which was actually filmed on land that we now own.)  Anyway, this morning it did not look like any Western backdrop.









While I was slowly driving through this winter wonderland, the sun disappeared and fog-banks rolled up the canyons. I could feel the temperature drop. When I got home, we covered some smaller Mexican cacti and aloes with boxes and blankets, but most of our plants are too big to be protected. Anyway, they have already survived the biting frost nights of 2010 and 2012, so it has to get very cold for them to be harmed.


However, I discovered today that a big barrel cactus is collapsing. It grew fast and furiously in the run-off from the roof and I'd always wondered how it could survive repeated flooding - so after this wet year its finally giving up.    

Happy 2015!