Saturday, June 24, 2017

Mothing at Clear Creek: The Subtle

Last weekend I had the pleasure of attending a moth night at Clear Creek Metro Park. The attendees saw a lot of moths over the course of the night, and I wanted to highlight a few species in particular. I'll be doing so in two posts; this post will focus on some of the more drab and subtle moth species of the night, while the next post will focus on the more showy and colorful moth species of the night!

EDIT: Click on this link to see the second post covering the showy moths of the night.

Mothing in Ohio

Moth nights are fun. The activity of mothing—a hobby involving the pursuit of moth diversity—centers primarily around moth sheets, like the ones pictured above. Moth sheets in themselves are nothing special; they're just plain white bed sheets. The magic lies in the lighting. Although normal household lights will attract moths here and there, you really need to use one of two types of special lights to really attract the moths. UV lights and mercury vapor lights are the weapon of choice here, with mercury vapor lights being the best of the best. This moth night at Clear Creek consisted of 4 mothing sheets set up throughout one section of the park. Several dozens of various moth species visited each sheet over the night, so let's jump right into some of the more drab and subtle species of the night!

Common Lytrosis (Lytrosis unitaria)
First up is the Common Lytrosis (Lytrosis unitaria). The Common Lytrosis is a rather large moth, coming in with around a 3 inch wingspan. I think this is a perfect species to start out with. If it were to fly by you, you might simply dismiss it as a big brown moth. But upon closer inspection, you would see all the minute and intricate details present in the wings. We humans tend to like the showy, eye-grabbing things in life, and we often skip over things that don't instantly grab our attention. But if you start taking a closer look at those "boring" things, you will soon find that they aren't so boring after all.

Barred Granite (Speranza subcessaria)
Mothing is like looking at abstract art. With abstract art, the appeal lies not within some straightforward meaning that the elements of the artwork create, but instead lies within the elements of the artwork themselvesthe colors and the contrast, the changing patterns across the canvas, the lines that take you on a journey through the artwork. The appeal of mothing, at least in my opinion, is the same. It's just fun to look closely at each species and see how all the colors, patterns, and lines interact with each other, and how that changes from species to species. This moth is called the Barred Granite (Speranza subcessaria), and its dark patches set among a pale gray background is a great example of contrasting elements.

Hemlock Angle (Macaria fissinotata)
One of the most enjoyable parts of mothing lies in the process of identification. This is the Hemlock Angle (Macaria fissinotata). At first glance, it looks almost identical to the previous Barred Granite, but closer inspection reveals differences in patterning. When I go mothing, I take photos of everything I see. I then spend the next week or so trying to identify each species from the comfort of my home. I use the Peterson Field Guide to Moths of Northeastern North America for this part. Identifying moths can be super frustrating, but in a fun way. Identifying these drab moths involves a lot of flipping from page to page through the Peterson Guide. Over and over. Again and again. Eventually you find the species you're looking for (but not always). As the name of this species implies, the larvae feed on Eastern Hemlock and occasionally Basalm Fir. Clear Creek Metro Park has a big population of Eastern Hemlocks, so it's no surprise that the Hemlock Angle is there!

Pale Metanema (Metanema inatomaria)
When I first saw this moth, I thought it was some species of emerald (subfamily Geometrinae), but it's actually the Pale Metanema (Metanema inatomaria) in the subfamily Ennomina. The caterpillar of the Pale Metanema uses various poplar species, and occasionally willows, as a host.

Bog Lygropia (Lygropia rivulalis)
This is a Bog Lygropia (Lygropia rivulalis). When it comes to most moths, we really don't know much information about their natural history. With most species, we at least know what types of plants the caterpillars feed on. With the Bog Lygropia, we don't even know that. In fact, from what I can tell we don't even know what the caterpillar looks like! There's so much fundamental information we're missing when it comes to the dark side of Lepidoptera.

The Beggar (Eubaphe mendica)
This is The Beggar (Eubaphe mendica), a rather common sight at mothing sheets. The common names of moths are strange. For decades, there were no common names. When people began "getting into" moths, those who made guides decided that they needed common names in addition to the scientific names. To solve this problem, they simply began making names up! Some common names were based off the scientific names. For example, the Bog Lygropia is called such because its scientific name is Lygropia rivulalis and it prefers wet and boggy areas. Other names are not as straightforward, and The Beggar is one such example. No one is exactly sure why it's call that, but the speculation is that whoever named it thought the dark patches on the wings looked like the holes in a stereotypical beggar's clothes.

Adult Woolly Bear
Next up is the Isabella Tiger Moth, which you probably better know as the Woolly Bear (Pyrrharctia isabella). A single individual visited the mothing sheet that night, and it happened to be a very worn individual that had lost a lot of its patterning. Luckily, there isn't much else that looks like an adult Isabella Tiger Moth. If you've ever wondered what the Woolly Bear turns into after metamorphosis, now you know! Side note: If you want to learn about some more "fuzzy" caterpillars, check out my previous post "Caterpillars of the Fuzzy Variety."

Arched Hooktip (Drepana arcuata)
I'll end this post with the Arched Hooktip (Drepana arcuata). The adults are your typical moth; the caterpillars, however, are unique. During the Arched Hooktip's caterpillar stage, the caterpillars like to be with other caterpillars of the same species. How do they find other caterpillars? They drum! One caterpillar will roll a leaf up, tighten it down with silk, and then crawl inside this new home. Once inside, the caterpillar will begin making vibrations by dragging parts of its anal segments against the leaf, drumming with its mouthparts, and performing a series of other actions. The resulting vibrations are a signal to any nearby Arched Hooktip caterpillars to come over and hang out in the new leaf shelter and eat together. This communicative behavior is super interesting, and very unique among the moths (at least from what we currently know). If you want to read more, here is a link to the original study: Invitation by vibration: recruitment to feeding shelters in social caterpillars

That's it for this post! I'll have the next post covering some of the showy moths up in a few days. Thanks for reading!

EDIT: Click on this link to see the second post covering the showy moths of the night.