Cicadas of the Cornell University Campus

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The face of a Linne’s Cicada (Neotibicen linnei). The large “grill”-like bump on the front of the face is the clypeus, which contains the muscles that act like a pump to power the cicada’s mouthparts.

The sizzling calls of cicadas are a familiar sound to anyone who has spent time outdoors on hot sunny days in late summer. Most cicadas sing from high in trees, making finding them a challenge. While they may all sound similar at first, their songs are all distinct and can be used to recognize species. I believe it is useful and fun to learn the calls of species that exist in your area. At the very least, it is a handy bit of trivia to have, and it’s also helpful in documenting biodiversity. With that in mind, here are the cicadas of Cornell University’s campus in Ithaca, New York. I have linked to recordings of each species from InsectSingers.com, a fantastic resource for cicadas.

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A male (left) and female (right) of the Linne’s Cicada. 

Neotibicen linnei, the Linne’s Cicada, is one of the two most common cicadas to be heard at Cornell. This species sounds a bit like a salt-and-pepper shaker to me. Its rattling buzz can be heard here. Individuals are nicely patterned in green and black, and have a prominent bend in the forewings that is a helpful guide to distinguish them from similar species. However this is not definitive, as some populations have less of a bend than others, and this should be used in conjunction with other traits to conclusively identify a specimen.

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Two females of the Lyric Cicada. Left is N. lyricen lyricen and right is N. lyricen engelhardti

Neotibicen lyricen, the Lyric Cicada, is the second of the two most common cicadas of Cornell’s campus. Its call is similar to the Linne’s but lacks the pulsations (hence the “lyric” moniker). It has been described as a syrupy buzz and can be heard here. I find that since these often drone on and on, they can become ‘white noise’ and fade from one’s notice easily. There is quite a bit of variation in the coloring of individuals. Around Ithaca there are two main color forms, known as N. lyricen lyricen and N. lyricen engelhardti. The former is patterned with greens, browns, reds, and tans while the latter is usually black with a very small amount of color on the pronotum, often in the shape of an anchor. These are not true subspecies and are better described as clinal variations. There are often intermediates in transitional zones such as Ithaca.

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A male Dog-day Cicada (Neotibicen canicularis).

Neotibicen canicularis, the Dog-day Cicada, is present on Cornell’s campus, but is not as abundant as the first two species mentioned. This is a more northern cicada, found in Canada and the northern tier of U.S. states. Its call is a high-pitched whine sounding like a buzz saw, and can be heard here. Dog-day cicadas look very similar to Linne’s cicadas but are quite a bit smaller.

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A comparison between a male Neotibicen linnei (left) and a male N. canicularis (right). Note the obvious size difference.

A few other species that I have not been able to document well here (or photograph) deserve brief mention:

I have heard Okanagana canadensis, the Canadian Cicada, numerous times around Cornell, but have been unable to find any. This is a very northern species on the southern edge of its range here. Males call from high in conifers. The call is an extended, cricket-like series of clicks (song).

Neotibicen tibicen, the Swamp Cicada, is a species that I think I have heard twice at Cornell, but both times were from quite a distance away. It is possible that these may have been Linne’s cicadas, as they sound rather similar (song). I will be listening for more this fall.

Finally, I must mention Neotibicen winnemanna, the Eastern scissor-grinder cicada. I heard this animal but once, at the edge of Cayuga lake in the early evening. However, there is no mistaking this cicada’s crazy call for anything else in the region. True to its name, it resembles the loud grating sound made by grinding scissors (song).

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A teneral (newly emerged) Linne’s cicada. At this stage they are very soft and vulnerable to predation. After several hours, the normal coloration sets in and the exoskeleton hardens up.

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A katydid’s nightmare

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Something is clearly wrong with this katydid – note the discoloration and the head hanging by a thread.

One day in late July of this year, I was out on an early morning walk on the trails around Cornell’s campus. Heading down some stairs down to the Fall Creek gorge, I noticed a dead katydid on the ground and picked it up. I recognized it as a male Scudderia fasciata, the treetop bush katydid. This species lives high in conifers, and has dark striped wings to match its habitat. I usually find them either at lights or by accident, so I figured I’d keep this one as a specimen. I noticed that its head was hanging by a thread and that the entire head and thorax seemed to be empty. In stark contrast to this, the katydid’s abdomen was brown and bulging. Perhaps it was rotting? As I peered at it closer, a scene straight out of the movie Alien – four huge wriggling fly maggots burst forth from the katydid’s carcass! I am not one to be creeped out by insects, but this was such a shock that I dropped the whole mess! This was an especially creepy scene given that katydids are some of my favorite insects. After a moment I realized that this was a golden opportunity to see what fly species would be parasitizing bush katydids in upstate New York. I gathered up the fly larvae and dead katydid and placed them in a container with some soil.

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This is what keeps katydids up at night – a sarcophagid fly parasitoid of Scudderia fasciata, as yet unidentified.

In a few hours, the maggots had dug into the soil and pupated. I had no idea how long they would remain there, but less than two weeks later I looked at the container and four small flies were flitting around. They were sarcophagids, a group known as “flesh flies” that are known for feeding on dead bodies but which also contains species that parasitize other invertebrates. They are quite difficult to identify from photos alone, but I kept the specimens and hopefully I will be able to pin an ID on them some day.

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A healthy male Scudderia fasciata, found nearby several days later (Ithaca, NY).

In search of the green-legged grasshopper

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Melanoplus eurycercus, a member of the Melanoplus ‘viridipes group‘ (Cameron, NY)

The genus Melanoplus contains around 240 species of mostly dull-colored grasshoppers distributed over most of the nearctic region, with one species in Eurasia. It is the most species-rich genus of Orthoptera in North America, and not surprisingly it is also one of the most confusing. Most species can only reliably be told apart by the male genitalia, and many short-winged species in the southern U.S. are still undescribed. I have had experience with quite a few species of the genus, but one always stood out to me as one I really wanted to see. The Melanoplus ‘viridipes group’ includes around 12 very similar looking species collectively known as green-legged grasshoppers, which may be subspecies or geographic variations of one (more study is needed!). They have very short wings as adults, barely reaching the middle of the abdomen, and are vividly patterned in green and black. From what I could gather, they occurred in small colonies in open areas at forest edges. They do not appear in most field guides and are not well known.

While looking through specimens in the Cornell University Insect Collection (CUIC), I discovered that one species in the viridipes group, M. eurycercus, had apparently been recorded in and around Ithaca. In early July, my dad visited me in Ithaca and we decided to make a search for this animal. We first checked out a few sites within a few miles of Cornell’s campus, turning up quite a few orthopteran species, mostly nymphs, and even another Melanoplus that was new to me – M. confusus. While this was certainly exciting, I knew that my real quarry was still out there. The next day we visited an area about 1.5 hours away from Cornell that Jason Dombroskie of the CUIC had recommended I visit, Cameron State Forest.

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Melanoplus confusus, the pasture grasshopper. A widespread species found in sandy grasslands in late spring and early summer (Ithaca, NY).

Not more than 10 minutes into the hike, I noticed a sluggish grasshopper slowly moving across the path and quickly grabbed it. Excitement – it was a female of M. eurycercus! I bottled her and started moving ahead looking for more. The trail emerged out into a small forest clearing and then headed into the forest again. In the clearing I found 3 more females on the ground, some of them with heavy parasitic mite loads. All were quite easy to capture, just managing a couple of weak hops before settling in the grass. Once I thought I saw a male sitting in vegetation, but it disappeared before I could get a better look. A male would be the big prize, since they are much more strikingly patterned and also have the distinctive genitalia that would confirm their identity. After searching the clearing for a while, I decided to move on, hoping to find similar habitats.

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Females of M. eurycercus are more drab looking, but still share the characteristic pattern of the males. 

We spent the rest of the day walking the trail down to a small prairie area. Many interesting insects were present, including more Melanoplus confusus, but eurycercus had not shown itself since the original forest clearing. When we arrived back at the clearing while returning to the car, I decided to have another look to see if I could find a male. I spotted several more females before I saw what I was looking for – a gorgeous male eurycercus sitting on some low bramble leaves. I carefully moved towards him, but once I got within about two feet of him he spooked and shot off into the vegetation, never to be seen again. I knew now what I was up against, and began systematically combing the clearing for more. It took me about 20 minutes to find another, sitting at the edge of a thick fern tangle. I moved ever so slowly to try and intercept him before he noticed me. Of course he did notice me and made a high-powered leap into the ferns, but I was prepared. I slammed my cupped hands down onto the spot where it looked like he landed, and then slowly lifted my fingers, feeling for a struggling little presence. After a minute, it was looking like he wasn’t there. Suddenly I saw movement off to the right – I had misjudged my grab! I pounced on that spot, and sure enough I had him. He was lovely, looking just like the images I had seen at BugGuide. I find it extremely rewarding to come across something that you have never seen before and immediately recognize it due to having seen it in books or online. Of course now that I had put out all this effort to capture this one male, I caught another one within minutes that was just sitting on the trail and didn’t even try to hop off. This one was a bit more beat up, missing an antenna and hosting several mites.

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A heavily mite-infested female of Melanoplus eurycercus

So the entire adventure was a success. Males and females of my quarry, plus another species that I hadn’t even expected!