Brisbane River from pedestrian walkway on Eleanor Schonell Bridge

Christmas is high summer in Brisbane. The skies are blue, the breezes warm and the birds often raucous. Barbies are more common than traditional Old World feasts, but some insist on sweltering away in the kitchen to produce the ham, turkey or roast they remember from childhood. The native Brush Turkeys have nothing to fear, though, although reputedly they aren't such bad tucker. Well, nothing to fear from cooks, but gardeners are likely to chase them out of the veggie patch when they try to turn it into a mound of compost.

Male Australian Brush Turkey

Surprisingly, although Australia boasts 38 genera of cicadas (32 endemic), and cicada-season runs most of the year (August through June), the City days have been free from the intense droning that I remember from field work in the nearby scrub. That's quite likely because it has been dry and many cicadas do not emerge until after the rains have commenced. Each evening at dusk, however, for about 15 minutes the air fills with the trilling of cicada, one of the Small Bottle Cicadas and probably Chlorocysta vitripennis (Westwood, 1851) or a closely related species. 

Female Small Bottle Cicada

The cicada's common name comes from the bloated and empty bottle-like bodies of the males: the females are more sleek and apparently less likely to escape the attention of young proto-entomologists in the morning. 

At this age insects are still a wonder and not a yucky bug

If you'd like to learn more about Australian Cicadas, then Lindsay Popple maintains an excellent website at:
http://sci-s03.bacs.uq.edu.au/ins-info/index.htm

Not yet Native of the Week: English Daisy

A nymphal ('larval') Tarnished Plant Bug on an English Daisy

In south eastern Australia, the English Daisy Bellis perennis L. is very common, so common that without knowing its origin, one might think it native. Like the Dandelion, the English Daisy is low growing and rather impervious to lawn mowers. Hence another common name is Lawn Daisy (aka Lawndaisy). However, it does very well in national parks that have been over-grazed by too many kangaroos too. Although weedy in Australia and naturalized in much of North America, it is rather pretty and not especially noxious unless one is very much the purist about their flora. 

Overbred and not hardy, but nice

The wild forms quickly revert to a plain white daisy, but numerous often very attractive horticultural forms are available at nurseries and they bloom for a long time. Summer before last we succumbed to some of these attractions, although knowing of the daisy's weedy potential. Fortunately, a rather mild central Alberta winter proved too much for these well-bred daisies and nothing re-sprouted in the spring. I suppose that means we could try again next summer and enjoy a few months of pretty blooms without worrying about letting loose a weed. Well, assuming no hardy genes showed up.

The nymphs of bugs slowly develop their wings, moult by moult

Friday Bug: Pine cones, molehills, and gophers

Spruce with cones, snow, and setting sun

The Home Bug Garden is situated in the Aspen Parklands of Alberta, so although spruce trees (White Spruce Picea glauca and Black Spruce Picea mariana) survive in protected areas of the landscape, the natural fire frequency tends to keep them from dominating and favours the patchwork of grasslands and aspen forests that give the parkland region its name. So, for example, if you walk through the Saskatchewan River Valley, you might notice that spruce trees grow mostly on the sheltered, wetter north-facing slopes of the ravine - and in the parks and yards.

Strange "Pine Cone" on my spruce

Actually, you are likely to find many kinds of spruce growing in peoples' yards. The Home Bug Garden has White Spruce, Black Spruce, and (not a native) Colorado Blue Spruce Picea pungens. Like all members of the Pinaceae, spruce produce male and female cones, and each of these cones are distinctive. But our White Spruce produces a third kind of "cone" and although these look very much like cones, they are not 'pine cones' or even spruce cones, but Cooley Spruce Galls caused by an aphid-like bug Adelges cooleyi (Gillette, 1907). 

Developing Cooley Spruce Gall on White Spruce

Blue Spruce are often considered the primary host of the Cooley Spruce Gall 'Aphid', but like many aphids and aphid-like bugs, these insects have a complicated life cycle where they alternate between two different hosts. In this case it is usually a generation on Blue Spruce and then a generation on Douglas Fir (Pseudotsuga menziesii). In Edmonton Blue Spruce does fine in yards, but I can't say I've seen a Doug Fir hereabouts, perhaps because they are only marginally hardy (Zone 4). In any case, only our White Spruce produces spruce galls, so something strange is going on. Most likely a cryptic species or host-specific strain that can get by on just spruce trees is present and it just isn't enough of a pest to have stimulated the research needed to clarify the situation.

Very cone-like gall- but who is it fooling?

In any case, why these tiny bugs make homes that look like cones, I have no idea. Who do they think they are fooling? Well, they do fool most people, even some entomologists the first time they see one, but they don't seem to fool the squirrels. I have yet to see a Red Squirrel feeding on a Cooley Spruce Gall. Perhaps they are too stuffed with spruce seeds, acorns, and baby birds, but I think they know the difference between a gall and a cone.

Do Red Squirrels know a gall from a spruce cone from a pine cone?

Not knowing such a difference or using an  incorrect name are the kinds of things that tend to annoy scientists. So, although Adelges cooleyi was once an aphid (family Aphididae) and called the Cooley Spruce Gall Aphid, these strange aphid-like bugs are better referred to as 'adelgids' now that they have their own family, Adelgidae. Since it is a common name, though, 'aphid' can be argued to be as correct as it needs to be. But the local custom of calling cone-like structures on spruce trees 'pine cones' always leaves me perplexed. Logically, pine cones grow on pines and spruce cones on spruce! Yet, the common name for all cones in my neighbourhood is 'pine cone', no matter what kind of tree it grows on. I don't want to make a mountain out of a molehill, but when I hear 'pine cone' I expect to see one.

Neither mountain nor molehill, but pocket gopher mound

Speaking of molehills, Alberta has none. True moles are small, burrowing mammals related to shrews that feed on insects and worms. Alas, none of the six species of true moles known to live in Canada is found in Alberta. If something  that looks like a molehill is thrown-up in your yard in the Edmonton area, it is a mound created by a pesky, root and top-feeding Northern Pocket Gopher. Therefore, with irrefutable logic, I say this must be a gopher mound! Yet my neighbours looks at me and sadly shake their heads at the ignorance on display, tax dollars wasted, and say 'Gophers don't make mounds, they dig holes!'

If this head could speak, it would declaim: "I am not a gopher!"

"Those are ground squirrels, not gophers, Richardson's Ground Squirrels", I insist to yet more head-shaking. 'Squirrels live in trees. Those are gophers, or you can call them pickets if you want, but they don't make mounds. You can go to the Gopher Hole Museum in Torrington and see for yourself.'  is the response that I get. 

If you can't beat 'em, join 'em: Two Gophers in Torrington, AB

About then, things are starting to get uncomfortable. Either the neighbour thinks I'm an idiot or that I'm pulling their leg. It's time to talk about the weather - something that everyone agrees on. It's as obvious as the snow on your cap or the picket in the pasture.

Gopher, Picket, or if you're argumentative, Ground Squirrel

Friday Bug: Broad heads, thin necks, and ant mimics

Reaching for the sky, getting it in the neck

I don't suppose anyone ever asked General Sherman his opinion on good bugs, but he may very well have said that the only good bug he saw was dead. Then again, may be not. Entomophobia isn't universal or even all that common in people who are both observant and enjoy being out-of-doors. Few, except perhaps eccentric entomologists, are entomophiliacs, but even fewer are completely misentomonic. For example, seemingly everyone loves butterflies, and even it they have reservations about butterflies in general ( (e.g. if their cabbage was just eaten by green worms), few would be rash enough to cast aspersions on a Monarch.

Alydus eurinus Say 1825 meets well-camouflaged Crab Spider

Thomas Say was one of those eccentric entomologists who may have loved insects. He described more than 1400 species of them and, as both a Quaker and a resident in the New Harmony utopian experiment, one might expect him to have held a benevolent attitude even toward bugs. In any case, we can thank Thomas Say for today's unfortunate bug meal for a near perfectly camouflaged crab spider (probably a species of Xysticus): Alydus eurinus Say 1825, a member of the Alydidae or Broad-headed Bugs.

Ant-mimicing nymph of Broad-headed Bug (Alydidae)

We have three species of Broad-headed Bugs inhabiting our pasture. The late Alydus eurinus, its congener Alydus conspersus Montandon, 1893, and its more colourful relative Megalotomus quinquespinosus (Say, 1825) all belong to the subfamily Alydinae and so are probably feeding on the vetch, clover, and alfalfa. In any case, they are common and as nymphs (or larvae if you prefer) do their best to look like black ants.

Mystery alydid mimic of black ant

Unfortunately, I can only key them as adults, so the nymphs remain mysterious, but rather good mimics of ants (presumably the common Formica podzolica and its relatives). 

Megalotomus quinquespinosus (Say, 1825)

The "Broad-headed" aspect of these bugs is more or less visible in the picture above - the head is rather broad compared to the thorax, at least compared to most of their relatives in the Coreoidea. But I do think this 'common name' (possibly made-up by an entomologist) leaves something to be desired. It's nowhere as evocative as, for example, the Tarnished Plant Bug, which also seems to make a habit of getting bitten in the neck by crab spiders.

A Tarnished Plant Bug gets it in the neck from another Xysticus.

Friday Stink Bugs: from the gaudy to the dowdy

Fall aggregation of stink bug nymphs

When I was a child, life was so much simpler. For example, a stink bug was a stink bug was a stink bug (although sometimes a stinkbug) and always Pentatomidae. 'Penta', of course means 'five', as in Pentagon, pentagram, etc., and 'tom' means 'cut'. Undoubtedly, this refers to the antennae of these bugs which are 'cut' into five segments. Most true bugs (Heteroptera) which get along with four or fewer. Alas, now we have two families to choose from: Pentatomidae and Acanthosomatidae. Well, whatever family they now inhabit, stink bugs usually live up to their names - they smell and, e.g. if one is too hasty eating a blackberry (not the electronic kind), taste bad too. Of course, many and possibly most 'true bugs' have thoracic glands that produce an odour that no one would mistake for a rose, but stink bugs are reliably smelly. Usually, though, they are not so brightly coloured.

Understated stinkyness - One-spotted Stink Bug

Take, for example, the One-spotted Stink Bug Euschistus variolarius (Palisot de Beauvois, 1805). Although not leaf green, as many stink bugs are, she clearly has no interesting in standing out. This is a full grown adult, but what I think is a nymph is similarly unremarkable.

What I think is a nymph larva of the One-spotted Stink Bug

Well, in my youth this was a nymph, as all immature terrestrial insects that did not go through complete metamorphosis were called. But now 'nymph' is out of fashion and hip entomologists call all immature insects, from maggots to hoppers, larvae. I'm sure the heuristic value of a holistic view of metamorphosis makes up for the loss of information conveyed by anachronisms like 'nymph'. Anyway, as long as someone knows that 'larvae' is plural and 'larva' singular, I'm unlikely to have a fit. (Although this information does not seem to be being passed down very well to the larval generation of entomologists.)

Twice-stabbed Stink Bug Adult and Larva: Cosmopepla lintneriana Kirkaldy, 1909 

Stink bugs are capable of advertising their distastefulness in both the adult and larval stage, as in the Twice-stabbed Stink Bug above. That our larval One-spotted Stink Bug does not is is interesting, in a rather intricately drab way. Why not advertise one's ability to make one go 'yuck!'? The One-spotted has a rather broad diet, everything from grass to veggies to fruit trees to other insects. So perhaps it finds being rather averagely drab an advantage in a variety of habitats. Sure, brightly coloured stink bugs may taste inexecrably bad, but who's to know until one tastes one?

Ground beetle that likes smelly food?

So is this predatory ground beetle (Carabidae) about to get the surprise of its life or does it like stinky food? Or perhaps caution will get the better of hunger. Alas, the photographer didn't stick around to find out, so we will have to end with a double mystery: and unknown larval bug and an unknown ground beetle.

Friday Phymatorama: Not as simple as it looks

Ambush Bug eating Cabbage White on Canada Thistle

This is the kind of picture any biological control entomologist or food-web modeller can instantly understand. The biocontrol person may see a natural enemy (the American Ambush Bug Phymata americana americana Melin, 1930) feeding on a pest (the Cabbage White Butterfly Pieris rapae (L., 1758)). If they are particularly perceptive, they also see that the pest is a potential pollinator of another pest, the misnamed Canada Thistle  Cirsium arvense (actually a native of Eurasia introduced here). So, the ambush bug is doing double duty. The food-web modeller might see it a little different: predator (bug), herbivore (butterfly), and primary producer (thistle), the typical three trophic-level food chain.

Ambush Bugs transformed into pests

Let's change the set-up slightly and look at another thistle. Here the female ambush bug (guarded by a smaller, darker male) is feeding on a Honey Bee (Apis mellifera L., 1758). The food web modeller doesn't see much different here, although they may wonder if the bugs would be better modelled as parasites of the plant (they are eating its pollinators). But, Hey! That's one of our bees! That bug is a pest, not a biocontrol agent/ natural enemy!

A slight change of focus turns good bugs bad

Let's change focus slightly again and look at another thistle plant. Here another pair of ghoulish bugs have a flower fly (Family Syrphidae: Helophilus sp.) by the tongue and the female bug is draining out its life's blood. Many flower flies are our friends, their maggots eat aphids, but this one's larvae feed on rotting vegetation. So, this is a more neutral interaction for our biocontrol person: the use of an alternative prey by a natural enemy/ pest of bees, depending on their perspective. This does complicate our food web model, though, the adult fly is an herbivore (feeding on pollen and nectar), but the larva is a detritivore (feeding on microbes and detritus), so a fourth trophic level needs to be added to the model as well as some omnivory (defined as feeding at more than one trophic level). The bugs are getting some of their energy directly from the detritivore level (as well as the herbivore level).

Flower fly that should've watched where it put its tongue

Let's shift focus slightly again, to another unfortunate fly. Here another pair of ambush bugs are feeding on a thick-headed fly (Family Conopidae), in this case Physocephala furcillata (Williston, 1882). Well, really the female bug is feeding and the male looking out for any other males that might be interested in his perch (but males aren't above sneaking a bite or two).

Ambush bugs feasting on a thick-headed fly

Our biocontrol specialist is likely to see this as more alternative prey behaviour. Good for keeping a predator around to feed on Cabbage Whites or bad if they are feeding on Honey Bees. But for the food-web modeller, this is just another complication.

Thick-headed flies mimic wasps, but are parasites of bumble bees

For our thick-headed fly is not a detritivore, but a fast-flying, wasp-mimcking parasite of bumble bees. They lay eggs on the bumble bees while they are in flight and the parasitic maggots eat out the bumble bees insides over a matter of a few weeks. This means we have to add another trophic "level" to our model - number 5 (detritivore, plant, herbivore, predator, parasite), at least as a concept, and because a predator feeding on a parasite is taking energy to one trophic level above the parasite (which in this case is functionally equivalent to our predator). 

Helophilus mimics a bee, but functions as both bee and detritivore (and dinner)

All of this is very destabilizing to our model food web: the more links (especially those between more than two levels), the more likely the model is to crash. And all of this comes from just looking at what one species of predator is doing on one afternoon in one field and on one plant. Imagine trying to model all of the interactions that must be going on in that one field with its dozens of plant and many hundreds of insect species. No wonder most modellers prefer to sit at their computers and play with their models and leave the real food webs to the bugs.

Not seeing eye-to-eye, but looking for the same thing: dinner