Handsome Trig Hijinks

by Carl Strang

Last year I followed a tip from Joe Balynas and found handsome trigs (Phyllopalpus pulchellus) established along the Cal Sag Channel, an extension of the Calumet River, in southern Cook County. This apparently was the first finding of the species in northern Illinois.

The handsome trig’s scientific name translates to something like “beautiful little leaf-mouth,” a reference to the expanded tips of its palps.

The Cal Sag Channel points toward the southeast corner of my own DuPage County, and I resolved that this year I would follow the trails along that waterway, and discover how far the trigs had come. That plan was blown to pieces on August 18. I was running along a recreational trail in Wheaton, central DuPage, when I heard the ratcheting mechanical trill of a handsome trig. I stopped to search, and was amazed to find four of the little crickets on the underside of a burdock leaf. Over the following weeks, I heard handsome trigs in scattered other locations in the southern half of DuPage County. I went back to southern Cook, and rode my bicycle west along trails that follow the Des Plaines River, past the point where it forms a complex with the Cal Sag Channel and the Chicago Sanitary Canal. Handsome trigs were audible at intervals along the trail, all the way into DuPage County’s Waterfall Glen Forest Preserve. This was one route by which the species may have reached my county.

What the hey? I have been able to recognize the handsome trig’s song for years, now. I had not found them in my own home county until 2017, and now suddenly they are in scattered spots across southern DuPage. Something about this year has favored the species, as they seem to be more numerous across the Chicago region. In 2017 I also added records for Will County, Illinois, Starke County, Indiana, and Berrien County, Michigan. This last is a new find for southwestern Michigan, but not for the state, as a recent paper reported them in southeastern Michigan (O’Brien, Mark F., and Julie A. Craves. 2016. Phyllopalpus pulchellus Uhler, the handsome trig (Orthoptera: Gryllidae), a confirmed Michigan resident. Great Lakes Entomol. 49:202-203).

The handsome trig is another species of singing insect that is expanding its range northward. It seems reasonable to think that they quietly have been spreading in DuPage County for years, but conditions in 2017 elevated their little local populations to the point where they drew my attention. I will be interested in following their numbers and possible ongoing range extension in coming seasons.

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Slightly Musical Coneheads Extend West

by Carl Strang

The slightly musical conehead (Neoconocephalus exiliscanorus) bears my favorite common name among all the singing insects of the Chicago region. That name was bestowed because W.T. Davis, who first described the species in 1887, thought its song was faint. He later changed his tune for good reason, as I find I can hear them easily through the open window of a car driven at a moderate speed. This was, in fact, how I came to add the slightly musical conehead to the species list for the Chicago region. Previously it was unknown in the northern third of Indiana, so I hadn’t expected to find it. Then, prowling the roads of the Indiana Dunes National Lakeshore with me in 2012, graduate students Gideon Ney and Nathan Harness, of the University of Missouri, recognized the katydid’s distinctive rapid buzz pulses.

Slightly musical conehead. They can be brown or green, and have longer cones at the tips of their heads than our other species in genus Neoconocephalus.

Subsequently I found slightly musical coneheads in several northern Indiana counties. They have not been a priority in my 22-county survey of the Chicago region’s singing insects, but I may make them one next year. In 2017 I added three counties: LaPorte and Lake in Indiana, and Kankakee in Illinois. Those last two additions extend the range significantly west, and provide the first observation of the species in the northern half of Illinois, according to the database in the Singing Insects of North America website.

Here is the updated map of my observations for this species:

Black dots represent the counties where I have found slightly musical coneheads through 2017.

And here is a recording of the song:

I often hear them singing in rural roadside ditches, and they are increasingly abundant as you go south. They sing only at night, in my experience.

Even More Melodious

by Carl Strang

Relatively little has been published about melodious ground crickets (Eunemobius melodius). These tiny insects with their beautiful trilling songs first revealed themselves to me at Indiana Dunes State Park in 2012.

Melodious ground cricket

They were abundant in an open, low wet forest associated with the shrub swamp that occupies a central position within that park. The ground there has relatively little vegetation beneath the trees, with abundant rotting logs on the ground, mosses, ferns, and some other vascular plants, but much ground with nothing but wet leaf litter. On another day, I heard a few melodious ground crickets in a similar habitat at Warren Woods in Berrien County, Michigan, and in a shrub swamp in Warren Dunes State Park, also in Berrien. There the matter rested until I heard a single individual in a bottomland forest in Tippecanoe River State Park, Pulaski County, Indiana, late last year. That observation planted an idea: perhaps this species is more abundant than I realized. Flood plain forests, resembling that original site at Indiana Dunes State Park, can be found along all the major rivers in the Chicago Region. Could melodious ground crickets be found in all those places? That set the stage for one of this year’s goals.

I first tested the idea on August 11 at the Momence Wetlands, a state-owned property in Kankakee County, Illinois. As I walked into this Kankakee River floodplain forest, I was struck by its similarity to other places where I have found melodious ground crickets, and before long I began to hear them singing. As I have come to expect, they were on the ground, in or close to rotting logs. I made sound recordings to analyze for confirmation, but the contrast between their songs and those of Say’s trigs (Anaxipha exigua), which were singing nearby up in tall herbaceous vegetation, made the identification clear in my mind before the analysis later confirmed it. According to the comprehensive database used to build the species’ maps for the Singing Insects of North America website, this was the first time the melodious ground cricket was documented in Illinois.

That same day I found them on both sides of that same river in Indiana, adding Lake and Newton County records. With that success in hand, I put some time into searching for melodious ground crickets in other counties and river systems. So far, I have found them along the Kankakee River in Starke and LaPorte Counties, and the Tippecanoe River in Fulton and Marshall Counties, all in Indiana. The significance of this is that the Kankakee River flows west to co-form the Illinois River and flow into the Mississippi. The Tippecanoe joins the Wabash River, flowing south to the Ohio River. Though the Yellow River (a tributary of the Kankakee) and Tippecanoe both cross through Marshall County, their watersheds are well separated by miles of dry moraines and sandy areas. The crickets were absent from bottomland areas that recently had flooded, but rotting logs in slightly more elevated portions consistently held singing crickets.

In Illinois, I found melodious ground crickets in Will County around the confluence of the Kankakee and Des Plaines Rivers, and upstream from there along the Des Plaines in my home county of DuPage. That is as far as I will go with this pursuit as the season winds down, but I expect to add more counties to the list next year. I conclude that at least in this limited but widespread habitat type, the melodious ground cricket can be sought throughout the southern portion of the Chicago region. Here is the map to date:

Map showing counties where I have found melodious ground crickets in the Chicago region, updated with 2017 observations.

I close this post with a couple sound recordings, both made at the Des Plaines Riverway Forest Preserve in DuPage County, Illinois, on September 6. The first, of a melodious ground cricket:

The second recording is the song of a Say’s trig:

Ground crickets, as the name suggests, sing from the ground (or, in the melodious ground cricket, sometimes from within a rotting log). Trigs sing from perches up in the vegetation. In this pair of recordings, the statistics quantify the differences you should be able to hear. The melodious ground cricket had a lower-pitched song, at 5.11 kHz, and a slower pulse rate, at 22/second. The Say’s trig’s corresponding numbers are 6.10 kHz and 31/second. The temperatures near the two singers bring out the contrast even more, the elevated trig at 17.7C and the ground cricket at 19C (i.e., if the trig had been singing at the ground cricket’s temperature, one would expect the dominant frequency and the pulse rate both to be even higher). The two species, as I mentioned above, often occur close to one another, making this difference worth noting.

 

A New North for Nebraskas

by Carl Strang

The Nebraska conehead is a katydid whose northern range limit is within the Chicago region.

Nebraska coneheads can be green, like this one, or brown. The entire underside of the cone is black.

This insect of forest edges and open woodlands sings at night, its high-pitched buzzes readily audible through the window of a moving car. It is common and widespread in the southern counties of the Chicago region, but becomes less abundant, and more locally distributed, farther north. Entering this year, I had found it in nearly all the southern counties. There was a record in the literature for McHenry County, Illinois, but I had not found it there or in neighboring Lake County. I made it a focus for this year’s searching, and was able to complete the map. On July 30 I heard them in both the Lake and McHenry County portions of Chain O’Lakes State Park. I tried to find them in northern Lake County, Indiana, on August 2, but was unsuccessful. On August 11 I found a group of them a short distance north of the southern Lake County border.

Here’s another view.

Chain O’Lakes State Park is not far from Wisconsin, so on August 18 I drove the rural roads of southern Kenosha County, just north of the park. Though the habitat looked suitable in places, there were no Nebraska coneheads. They are already vanishingly thin in Lake and McHenry, so this was not surprising.

The Chicago region range map for the Nebraska conehead. Black dots indicate the counties where I have found the species. The red star marks Chain O’Lakes State Park, the northernmost known location in the region.

For my purposes, I am satisfied that I can close the book on Nebraska coneheads and focus on other species.

 

Currency and Milestones

by Carl Strang

Last week, in a location just north of the Indiana border, I heard a single long-spurred meadow katydid singing in Berrien County, Michigan.

Long-spurred meadow katydid

Earlier in the season, I had found that species in two locations in Kane County, Illinois. These results amounted to two county records and a milestone in my 22-county survey of singing insects in the Chicago region. As I outlined in a blog post last year, the currency by which I measure progress is county records. The goal for each species, however, is either to find it in every county or to conclude that I have reached the limit of its range in the region. When I do so, as now is the case for long-spurred meadow katydids, it marks a milestone in the survey. I no longer need to expend time and effort in searching for that species.

The resulting map for the long-spurred meadow katydid. Black dots indicate counties where I have found the species, and red stars indicate the northernmost locations in Kane, DuPage, Cook and Berrien Counties (i.e., the range limit).

With 100 species and 22 counties, there theoretically could be as many as 2200 county records and 100 milestones. Many species are limited, however, with the edge of their range occurring within the region (as in the long-spurred meadow katydid) or else by having ecological needs which cannot be met in every county. As of this writing, I have a cumulative total of 1129 county records and 32 milestones. The year’s count is up to 87 county records. I hope to reach 100, but if I do, this will be the last year in which I can do so, as I estimate that there will be a total of only about 200 more to be found in future years. The wild card here is in the singing grasshoppers. I have not been very successful in finding these, so if I hit upon a method that opens the door to finding them, that could greatly increase the number of potential county records to be added. At this point, however, it seems more likely that most of these are very limited in their distribution.

 

Closing the Book on Prairie Cicadas

by Carl Strang

The prairie cicada is a small (1-inch) insect that occurs in a few remnant prairies in northeast Illinois. Work by Dennis Nyberg and associates at the University of Illinois Chicago has revealed much of what is known about them in the state. I first gained experience with this species a few years ago at the UIC’s Woodworth Prairie in northern Cook County, then quickly discovered them in two DuPage County locations. I expected then that I would find them consistently in prairie remnants, but this has not proven to be the case.

Prairie cicada, June 2017

Recently I finished checking the last of the remnant prairies I know about in the Chicago region, and have not added any more locations to the UIC group’s 8 sites (they also listed 3 sites in downstate counties). I have not found them anywhere in the region’s Indiana or Wisconsin counties.

All the sites are small, so all the populations are small and vulnerable. Mated females do not disperse beyond their little prairie plots, as far as anyone has been able to determine. If the species is to survive in the region, the landholders (mainly forest preserve districts and railroads) will need to continue managing those sites so that the prairies can persist, and prairie cicadas with them.

Closing the Book on Protean Shieldbacks

by Carl Strang

The protean shieldback is the most common native predaceous katydid in the Chicago region. Because of their broad diet, they can develop quickly in the spring. They begin singing in June, the males broadcasting their extended, high-pitched rattles in open woodlands, as well as prairies with at least a little woody vegetation.

Male protean shieldback in singing posture.

At first, they begin to sing in the late afternoon from hidden locations near the ground. When it becomes dark, they climb up onto open perches, often on woody stems. As their season progresses, they begin to sing later, until a few begin at dusk and most wait until dark.

This year I learned that they are more abundant than I had realized. I need the SongFinder, a pitch-lowering electronic device, to hear most of them. With that final lesson, I sought them out in portions of my 22-county Chicago region where I had not found them before. That mission was successful, the final 15 counties resulting in some late-night returns home. At this writing, they still are going strong.

A Mystery Solved: Miogryllus!

by Carl Strang

In 2014 I first heard what sounded to my ear like a singing striped ground cricket, but it seemed too early in the season. It was June 21, at Hoosier Prairie Nature Preserve in Lake County, Indiana. I made a recording, then moved on to the Indiana Kankakee Sands, where I heard it again. Though these sites are a bit south of my DuPage County home, I didn’t hear striped ground crickets in DuPage until July 13. The next year I heard the same odd songs, this time at the Midewin National Tallgrass Prairie, in the middle of Will County, immediately south of DuPage. This was even earlier, on June 10. Again I made a recording. And again, I did not hear striped ground crickets in DuPage until, as it happened, July 13. In 2016 I went down to Midewin on June 28, and heard the same early, striped-ground-cricket like songs. This year, the same story, Midewin, June 23. This time, though, it seemed to me that the songs were not quite right for striped ground crickets. They seemed too precise, too even and strong. Here is a recording I made in the same location on June 28:

I went back and listened to my earlier recordings, reviewed my list of hypothetical singing insect species for the Chicago region, then checked reference recordings of their songs. The early songs did sound different from my recordings of later-season striped ground crickets, an example here:

The odd, early songs seemed to be a match for one of the hypotheticals, the eastern striped cricket, Miogryllus verticalis. Furthermore, references indicated that M. verticalis is an early season species, most abundant in June. I drove back down to Midewin on June 28. Trying to zero in on the singers was very frustrating; they seemed to have a ventriloquial quality. Eventually I flushed out and captured a female cricket near one of the singing mystery males. Looking through the clear plastic cup that held her, I could see that she was indeed an eastern striped cricket. I took a couple photos looking down into the cup. It was well that I did, because when I tried to get her positioned for a shot from the side, she gave me the slip and I was unable to recapture her.

Female eastern striped cricket, dorsal view

She was just a little smaller than a spring field cricket, which species was sharing the grassy meadow where Miogryllus were abundant. This confirms that eastern striped crickets are established in the southwestern portion of the 22-county area I define as the Chicago region. They would seem to represent yet another example of a range extension northward by a singing insect species.

Bioblitz 2017

by Carl Strang

This year’s bioblitz in the series organized by the Indiana Academy of Sciences took place on June 10-11 at the White River Woods and McVey Memorial Forest, two sites near Muncie. This early in the season I did not expect much in the way of singing insects. Spring trigs were common, so I gained more experience with them, but there was a surprising lack of spring field crickets.

Green-striped grasshoppers still were displaying at McVey.

A Roesel’s katydid at White River Woods

I joined Jeff Holland’s Purdue University group at their light station in the forest at McVey, assisting as a moth spotter. A few photos from that night follow.

Banded tussock moth

Io moths, when resting, do not show their dramatic hind-wing eye spots.

Barred granite

A few walnut sphinxes were attracted to the light.

A couple black-sided pygmy grasshoppers also made an appearance.

Male black-sided pygmy grasshoppers have a distinctive white, black and brown pattern.

Females are all dark. The pygmy grasshoppers are distinguished not only by their small size, but also by the pronotum’s extension over much of the abdomen.

 

Closing the Book on Sulfur-wings

by Carl Strang

The sulfur-winged grasshopper is an early season species that I wanted to close out this year, in my regional survey of singing insects. Though it probably occurs in all 22 of the counties in my survey region, it is common only on soils heavy in gravel or sand. I targeted 3 counties with such soils where I had not yet found this crepitating (wing-rattling) grasshopper: Walworth in Wisconsin, LaPorte in Indiana, and Berrien in Michigan.

Success came first at the Lulu Lake natural area in Walworth County. I did not find it in the Nature Conservancy portion of the property, but gravel-hill openings in the forest on the state nature preserve side proved to have a good population.

One of the series of photos documenting sulfur-winged grasshoppers at Lulu Lake.

Subsequently I found them in the Lake Michigan coastal zone in LaPorte and Berrien Counties. In the process I learned a final lesson from the grasshoppers: they don’t like loose dune sand, and need to be sought a little farther inland, where plants and the accumulation of organic matter have made the soil more stable. That closes the book on sulfur-winged grasshoppers as far as my survey is concerned, and I will put my time into other species at this point of the season in future years.

The updated Chicago region sulfur-winged grasshopper map, marking counties where I have found it.

 

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