Jul 272012
Banded Tussock Moth - Halysidota tessellaris

Banded Tussock Moth – Halysidota tessellaris – Toronto, Ontario

While some common names are great descriptors of a moth’s biology, some can be rather deceiving. Take the Banded Tussock moth for example, which although banded, isn’t a true tussock moth! While the “true” tussock moths are in the subfamily Lymantriinae, this moth is actually a tiger moth in the Arctiinae. The larvae of this moth have large tufts of hairs that are reminiscent of those found on “true” tussock moth caterpillars, which is where the common name comes from. These tufted larvae can be found feeding on a wide diversity of deciduous trees.

Tiger moths are known for their ability to hear incoming sonar pings of bat predators, and some have even evolved sonic countermeasures. The Banded Tussock moth was one of the first moths shown to protect themselves from bats by emitting high-frequency sounds (Dunning & Roeder, 1965). Remembering back to my undergraduate Physiology classes, I recall there being 2 ways in which these sonic displays could deter bats: 1) as a warning that the moth was distasteful and the bat should move on to something more tasty (the acoustic equivalent to the bright colours found on many other tiger moths and insects), and 2) some moths emitted a frequency so close to the bat’s sonar that they could disrupt the bat’s orientation and become hidden in a curtain of sonic feedback. Which method this species enlists I’m not sure, but I find it amazing that some moths have adopted such extreme defenses.

Of course, being loud isn’t going to save you from all potential threats, like the tachinid parasitoid Blondelia hyphantriae.

Dunning, D.C. & Roeder, K.D. (1965). Moth Sounds and the Insect-Catching Behavior of Bats, Science, 147 (3654) 174. DOI: 10.1126/science.147.3654.173

Jul 262012
Basswood Leafroller - Pantographa limata

Basswood Leafroller – Pantographa limata – Toronto, Ontario

This may be one of my new favourite Ontario moths; I find the colour and pattern of the wings to be quite striking. It also has one of the more literal common names, as the larvae role up leaves of a diversity of trees, including basswoods (Tilia). Although called a leafroller, this moth belongs in the family Crambidae, not the Tortricidae where most other leafrollers are found.

The Basswood Leafroller is host to tachinid parasites in the genus Carcelia, as well as Nilea erecta. Basswood Leafroller caterpillars have also been considered “Tasty” to Paraponeura clavata ants in Costa Rica.

Jul 252012
Fall Cankerworm - Alsophila pometaria

Fall Cankerworm – Alsophila pometaria – Geometridae – Guelph, Ontario

Not all moths have showy wings, or even wings to begin with! The Fall Cankerworm (Alsophila pometaria) is a moderate pest in the landscaping industry as the larvae skeletonize leaves of several different trees and as you can see here the females are completely wingless. Females emerge from the leaf litter in the fall and climb up trees and other vertical objects to attract mates (males are winged). As the name suggests, adults are only active in the fall.

The Fall Cankerworm is host to a variety of tachinid species: Blondelia eufitchiae, Cyzenis albicans, Gonia sagax, Blepharomyia spinosa, Smidtia fumiferanae, Phryxe pecosensis, Phryxe vulgaris, Phorocera slossonae, Tachinomyia nigricans, and Winthemia rufopicta.


Parasite information from A Host-Parasite Catalog of North American Tachinidae Diptera (Arnaud, 1978).

Jul 242012
Virginia Ctenucha - Ctenucha virginica moth

Virginia Ctenucha – Ctenucha virginica

I may be nearly useless with moth identification, but this is one I know by heart. Of course, this isn’t really brag worthy since there aren’t many moths with an iridescent blue thorax and yellow head, but I’m working on baby steps here.

Just because I can identify it doesn’t mean I can place it in the correct family however! When I was an undergrad (back in the day when I had to walk 10 miles uphill both ways, etc) I was taught the tiger moths were a family unto themselves. Since then however, they’ve been sunk into the family Erebidae, causing me much confusion.

The Virginia Ctenucha feeds on a variety of grasses and sedges as a caterpillar, and adults are active from late spring to mid summer.

What feeds on Virginia Ctenucha though? Compsilura concinnata, a tachinid fly that was introduced to North America to combat Gypsy moth (Lymantria dispar) in the late 19th and early 20th century. As is wont to happen with poorly understood ecology and introductions, Compsilura concinnata turned out to be a broad generalist, and is right at home within a wide diversity of caterpillar hosts. There’s concern that this “new” parasitoid is a contributing factor to declining saturniid moth populations in eastern North America, but the fly appears to be under heavy pressure from a hyper-parasitoid species of trigonalid wasp, which appears to be keeping fly populations low enough to prevent eradication of native moths.
Kellogg, S.K., Fink, L.S. & Brower, L.P. (2003). Parasitism of Native Luna Moths, (L.) (Lepidoptera: Saturniidae) by the Introduced (Meigen) (Diptera: Tachinidae) in Central Virginia, and Their Hyperparasitism by Trigonalid Wasps (Hymenoptera: Trigonalidae), Environmental Entomology, 32 (5) 1027. DOI: 10.1603/0046-225X-32.5.1019

Jul 232012
Waved Sphinx Moth - Ceratomia undulosa

Waved Sphinx Moth – Ceratomia undulosa (Hodges #7787)

I can’t help but get a little excited about sphinx moths; they’re so big and cool looking that I just can’t resist taking a photo (foreshadowing: expect to see more sphinx moth photos by the end of the week). This individual came in while I was blacklighting at the Rouge Valley BioBlitz, right in the heart of Toronto.

The Waved Sphinx Moth feeds on a variety of plants as a caterpillar, including ash (Fraxinus), privet (Ligustrum), oak (Quercus), hawthorn (Crataegus), and fringe (Chionanthus). and can be found across much of eastern North America throughout the summer.

As for parasites, being big and widespread has it’s drawbacks, as this species has at least 10 species of Tachinidae known to develop in it (Belvosia borealis, Compsilura concinnata, Drino incompta, Chetogena claripennis, Chetogena floridensis, Hyphantrophaga hyphantriae, Hyphantrophaga virilis, Lespesia aletiae, Lespesia frenchii and Winthemia datanae).


Moth identification and biology from the Peterson Field Guide to Moths of Northeastern North America (Beadle & Leckie, 2012).

Parasite information from A Host-Parasite Catalog of North American Tachinidae Diptera (Arnaud, 1978).

May 112011

A few days ago I was walking through the University of Guelph Arboretum taking some down time and trying to get back into the photography groove when I noticed a peculiar sight…


Tree weeping sap covered in insects

The trees were weeping, and dozens of flies were lapping up the sweet, sweet tears! Since there were several of these patches on two nearby trees (my tree bark ID skills are severely lacking, I’m a leaf man) and the wet marks were 4 to 10 feet off the ground, I felt it was a safe guess that it wasn’t a territorial marking (unless the UofG men’s basketball team was having a summer camp…), and last I checked I wasn’t in Fangorn Forest, so I did a little detective work to discover the story behind the sadness.

Closer inspection revealed these curious holes:

Yellow-bellied Sapsucker holes drilled into tree bark

My first thought was to scan for long-horned beetles (Cerambycidae) or perhaps metallic jewel beetles (Buprestidae), but after seeing nothing but flies and wasps, I took a closer look and noticed that the holes only pierced the bark, and not the xylem (aka sapwood). It dawned on me that what I was looking at was a tricky, sticky lure set by a bird I’d seen plenty of times before in the Arb; the Yellow-bellied Sapsucker (Sphyrapicus varius). This crafty woodpecker will cause superficial injuries to a tree, and then sit back while the sap flows free. The bird will then return to the tree and pick off the insects which are feeding on the sap, as well as some of the sap itself! Clever bird…

Pretty cool biology, so I took the opportunity to see what sort of insects were at risk of becoming an early spring brunch for the hungry sapsucker.

I observed a few butterflies when I first approached the trees, but they quickly flitted away, not to return while I was there. I’m by no means a Leper (i.e. a Lepidopterist), but I think they may have been Red Admirals (Vanessa atalanta, Nymphalidae), which are one of the earlier butterfly species to be found in Southern Ontario.

There were a number of hymenopterans taking advantage of the Saturday afternoon bounty including many Ichneuomoid wasps and this fuzzy female:

Andrenid bee eating tree sap Andrenidae

This andrenid bee (Andrenidae) seemed quite content to sit and lap up the sugary sap running down the tree bark, not caring when I moved in and out trying to get a decent photograph of it’s amazing hairdo.

Tenthridinidae wasp eating tree sap with a calliphoridae and muscidae fly

While the bee was busy enjoying a solitary meal, this sawfly (Dolerus unicolor, Tenthredinidae) was more than happy to share the sap with a couple of calyptrate flies (a blowfly [Calliphoridae] on the right and what I believe to be a Muscidae at the top). In fact, the calyptrates made up the vast majority of the insects visiting the tree, in some places packed so tightly you couldn’t see the tree for the flies!

Blow fly Calliphoridae sponging up tree sap

The sponge-like mouthparts found in many calyptrates are well demonstrated in this blowfly (Calliphoridae, possibly subfamily Chrysomyinae). You can see the maxillary palpi sticking straight ahead as the membranous labrum and associated sclerites mop up any residual tree sap on the bark.

Scathophaga sp. Scathophagidae

Another, lesser known calyptrate family was also making an appearance; the Scathophagidae. I could make out what looked to be two species of scathophagid, including this Scathophaga sp. perched nearby awaiting its turn at the sugar shack.

Tachinidae fly on tree drinking tree sap

Not everything went according to plan on this outing however, as I made a major n00b move – I forgot to pack specimen vials! While normally I’d have a dozen or so snap-top vials in my camera bag in case I ran into something which needed to be examined at a later date and added to the University of Guelph Insect Collection, after transferring my photo equipment into my new camera bag (courtesy of the best wife ever), I neglected to throw in the vials! The first rule of entomology (besides “ALWAYS talk about entomology”) is to collect the damn specimen, and as luck would have it, I came across a fly which I instantly wanted to collect (pictured above & below).

Tachinidae with tree sap fly

This Tachinidae caught my eye right away, and after several attempts, I managed to get a couple of decent images. Unfortunately, tachinid flies are one of the most diverse groups of animals on the planet, and the specimen would be vital in identifying it to the genus or subfamily level on my own. A lesson learned, and needless to say I threw a couple of vials in my bag as soon as I got home!

After getting my fill of photos and not having any means to collect some specimens, I decided to pull back and let nature take it’s course. While I never saw the sapsucker, I certainly appreciated the opportunity it created, allowing me to photograph a great diversity of flies and wasps!