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More Urban Species in the yard

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This weirdly attractive fly is Delphinia picta, a picture-winged fly. The wings are distinctively patterned, and moved in a rowing motion as the fly walks along--perhaps a sexual display or some kind of defense? I found no explanation for the horse-like shape of the fly's head, only the note that one scientist observed "adults feeding on fermenting beetle frass protruding from the bark of a black locust." Larvae feed on decaying vegetable matter, including compost and rotten onions.

More Urban Species by my porch light

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This little moth--just over a centimeter wing span--was by the porch light. At that scale it looked like a dainty pretty thing, but close up you can see a lot of detail in the wing pattern. Are those markings meaningful to the animal? I got a fairly confident identification from a moth ID group, calling it Idaea dimidiata, the "single-dotted wave." This species is native to Europe, found throughout the north of North America. It's larva is a small inchworm that must eat some plant found on both continents.

3:00 snapshot #1621: Tuesday

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Waxworms are moth caterpillars that, in nature, develop in the hives of honeybees, feeding on the wax and other products therein. Because they spend their larva lives in the dark of the hive, they are colorless and maggot-like.

They happen to be very hardy caterpillars that will survive a relatively long time if kept at a low temperature--say, in a refrigerator. This has contributed to them being incorporated into the captive insect food industry. These are intended for cotton-top tamarins, which are tiny monkeys. They are likewise fed to captive birds and reptiles. They are also perfectly good food for humans, and if you read the book "Edible" by Daniella Martin, you will find a simple recipe for preparing them. (No, I haven't tried them yet.)

More Urban Species in my shower

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I get that most people don't like it when they find an insect or spider in their shower. You're naked, you've taken your glasses off, you're as vulnerable as you get, suddenly you have to deal with a bug. My reaction was, "Oh god, yes! I better go get my camera!" It's been such a long winter--cold and snowy with insects all hidden away for months--that I was honestly delighted to see this tiny beetle on the shower wall. This one looked a little familiar to me--it's shape and colors look very much like the scarlet malachite beetle I found in the yard back in June of 2012.

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Only this beetle was a fraction of the size of its larger cousin. It turns out that this is Anthocomus equestris, in the Melyridae family of soft-winged flower beetles, in the same subfamily Malachiinae as the scarlet malachite beetle. This one appears to have no common name, however, aside from "soft-winged flower beetle" among many of its relatives. Also I can't find the origin for the scientific name, which seems to mean "Mounted flower-enjoyer." Flower-enjoyer makes sense, since these beetles are found on flowers, probably eating pollen, but the "equestris" business confuses me--chivalrous? on horseback? Dunno.

Like the scarlet malachite beetle, this beetle is a Eurasian import--insects from that continent had several millennia of practice living among humans and their buildings, and are often brought to our continent without the predators and parasites that keep them in check. Therefore, when a North American finds a small arthropod in their house there's a better than even chance that it's a species from across the pond.

Indoor winter visitor

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A small delicate fly, about the size and shape of a mosquito, drifts in from the porch door into the kitchen. I stifle the impulse to swat it--it's a reflex, an unconscious motion that many of us succumb to, to smash a flying insect. But mosquitoes are so rare in December in Boston that if I saw one it would be better to catch it and identify it for novelty's sake if nothing else.

You can see by the way this fly stands on the wall, all six legs down, that it is not a mosquito. Most mosquitoes land head down, back end up, with the last two legs off the surface--all the better to take a quick drink of you. To that point look at the fly's head: no proboscis.

This harmless visitor is a winter crane fly Trichocera sp. It is active in the warmer parts of the colder months, an adaptation that allows it to avoid predators. Their larvae are little white maggots that chew their way through compost and manure and wet vegetation, benefitting from habitat concentrated around humans such as leaf piles, rodent burrows, and even stored root vegetables.

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One of my favorite things about crane flies is how their halteres are big enough and exposed enough to be visible to the naked eye.

Late November visitor

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Of every 200 moths I see in November, 199 of them are winter moths. This one, much more robust and dare I admit it more charismatic, was perched on the sink in the upstairs bathroom.

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You can see its scales are worn away on its head and thorax. This is a stalwart survivor, battered by time and the elements, and clever enough to slip into the warmth of the house. Someone on the facebook Mothing and Moth Identification group identified it as the adult of the armyworm Mythimna unipuncta. This species is found on both New World continents as well as Europe, Africa, and Asia, not to mention various islands. The caterpillars feed on a broad range of grass species--an order of plants found anywhere modern humans are growing food or playing fields.

More urban species: Hallowe'en aphids

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Some zookeepers were passing through one of their exhibit gates only to discover their skin and clothes stained by some purple substance. There were also a lot of flies and yellow jackets flying around. Finally someone noticed the aphids.

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A lot of aphids. The purple staining came from the crushed bodies of hundreds of aphids. Since aphids normally spend nearly their whole lives on their host plant, this behavior is a little strange. My best guess is that they overpopulated their host plant and dispersed out of necessity. Above this gate is one of many Austrees in a row. An Austree is a ornamental willow hybrid developed for use as a windbreak--it grows straight and very fast. Researching willow aphids, I found that they feed on second year growth; there would only be so much of this kind of growth on each tree.

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Most aphids are wingless, but some are born with wings, allowing them to fly to new host plants to establish new colonies.

Aphids famously produce a waste material called honeydew, which other insects use as a food source. Ants are usually the ones you think of accompanying aphids, but in my experience yellow jackets are drawn to aphids in the fall, when the yellow jackets are desperate for a source of liquid food. (Yellow jacket adults can't feed on solid food, so they feed their larvae solid food and the larvae regurgitate a liquid the adults can eat. In the fall, the queen stops producing new larvae and the workers must find liquid sugar on their own, thus the misery they cause to late summer soda drinkers and ice cream eaters.)

Looking on bugguide, it's clear that these are genus Pterocomma, large aphids that feed on willow or poplar. They most closely resemble, in appearance and behavior, other aphids on bugguide not identified to species, but named "halloween aphids" by one user. Their coloration plus their sudden appearance in October justifies this common name to me. I hope some aphid expert identifies them to species (and keeps the name "halloween aphid.")

More Urban Species: Acorn weevil

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Acorn weevil, Curculio sp.

I caught this acorn weevil as it flew around the zoo library. There are no oak trees in there, so it must have hitched a ride on a human being. Just outside, however, stands the grand red oak forest that is Boston's Franklin Park. Strangely, this is the second time I've included a weevil caught indoors in this blog; likewise, when I led a reporter from The Weekly Dig around a few years ago, our first wildlife encounter was with a weevil. I don't think of weevils as being all that common (I don't think of weevils all that much at all), but they comprise the most numerous family* within the most numerous order (beetles) of all animals.

Acorn and nut weevils are numerous indeed, with at least 22 species feeding on seeds of oaks and others feeding on hickory, chestnut, and pecan tree seeds. Adults seek out acorns still on the tree, use their preposterous proboscis to drill through the nut shell, and feed on the meat inside. Females lay their eggs into these holes, and the legless larvae hatch and live within. The larva is somewhat protected by the seed shell, but a nut is no real obstacle to a squirrel, who will happily eat a fat weevil grub. One study showed that gray squirrels immediately consumed weevil-infested acorns 3/4 of the time they were available.

If the grub survives uneaten, it waits until the acorn falls, then chews its way out and digs into the soil to pupate. One genus of ant, Temnothorax, may move into the vacant nut to build its tiny nest. Conversations with an entomologist friend suggest that the pressure of weevil predation is a possible explanation for (or important factor influencing) year to year feast or famine acorn production.

*Wikipedia claims a controversy on this fact, suggesting that some experts assert that rove beetles rival weevils for numbers of species, but does not specify what experts those are.

(I'm a little worried I'll be remembered more for my awful fingers than for my contributions as a naturalist)

100 More Species #100: Chinese mantid

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Chinese mantid Tenodera sinensis

The praying mantis, with its centaur body plan, head that swivels to look at you, and fierce raptorial forelegs is an immensely charismatic insect. I wonder how many (other) naturalists would list an early encounter with one of these creatures as an influence toward their studies. Even people who don't like insects like mantids (as we nature nerds call them), and today I had two different coworkers show me cellphone pics recording their encounters. One made a gesture indicating a length of 8 to 10 inches for the one she saw, which is of course impossible, but underscores how large these creatures are. In fact the Chinese mantid is the largest mantid found in North America--this individual was about four inches long. When you consider that their closest relatives are cockroaches, and what a likely human reaction would be to a four-inch cockroach, then the size seems to matter.

Alas, as you might have guessed, the Chinese mantid is not native to my yard or the region. Chinese mantids and a related European species are sold as beneficial predators at garden shops. They are more visible, if not more common, than native mantid species, and there is some worry that they are displacing North American mantids. I have mixed feelings about the Chinese mantid, since despite the harm they may be causing, they inspire awe and wonder about nature and insects.

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Holding out for a really good 99

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This moth was attracted to the porch light, then slipped past the threshold to the kitchen wall. I caught it up and chucked it outside.

The chances are really good that this is the "dingy cutworm moth," an unkind name for a lovely little animal. The larva is distinguished from its close relatives by being darker and less well-patterned, thus "dingy." The adult looks enough like its close relatives that even the entomosnobs at bugguide declare "Species identification a bit difficult."

There are four lookalikes that are possible visitors to my yard, including the awesomely named "subgothic dart." Alas, I'll let this one go by as Feltia sp., unidentified dart moth, and wait for something to knock my socks off (or at least have a firmer identification) for the penultimate species in my 100 species project.
EDITED TO ADD: I should hold out for a better picture, too. Yeesh.

(Cutworms are caterpillars that eat young plants, cutting them at the soil level, like this one.)


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