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.

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Sound Ideas: Coneheads

by Carl Strang

When I mention the coneheads to people unfamiliar with singing insects, the response almost always is a smile. I have to agree: one reason why the slightly musical conehead is my favorite singing insect (at the moment) is that name. Our coneheads are all katydids in genus Neoconocephalus. I have been fortunate to spend some time in the field with Gideon Ney, a Ph.D. student at the University of Missouri who is working out of a lab led by Johannes Schul that has done a lot of work with the evolution of that group. Thanks to Gideon I am aware of two species of coneheads that are not supposed to occur as far north as the Chicago region, but turn out to be at least locally common. Today I share recordings of the 6 documented species in the region. Warning: these are not delightfully musical or even (despite the name mentioned above) slightly so. We’ll ease into it with one that is somewhat pleasant to hear: the sword-bearing conehead. Its song:

That recording was made in a grassy upland meadow, typical habitat for the species, but close enough to the edge of the woods that a few common true katydids came through loud and clear. The conehead’s song is the continuous string of rasping ticks or brief buzzes. It has been compared to the sound of a sewing machine or a distant steam locomotive.

The sword-bearing conehead is named for the very long, straight ovipositor on the female.

The sword-bearing conehead is named for the very long, straight ovipositor on the female.

The next species also has a discontinuous song. The slightly musical conehead was given that name because W.T. Davis, who described it, thought it was not very loud (though he later changed his mind on that point).

The rasping sounds are easy for me to hear even with my older ears. This is a wetland species, and the males typically sing in unison.

The coneheads are named for the structure on the tip of the head, especially prominent in the slightly musical conehead.

The coneheads are named for the structure on the tip of the head, especially prominent in the slightly musical conehead.

Another species with an interrupted song is the Nebraska conehead.

The buzzes are not as rough as in the previous species, and will be heard in bushy undergrowth of woodlands, or sometimes bushes out in fields. In the southern part of the Chicago region, where the species is more common, the males sometimes sing in unison as well.

Male coneheads often sing head down. It has been speculated that the cone helps them penetrate the vegetation beneath when they are disturbed and drop to hide. Nebraska coneheads have medium sized, all black cone undersides.

Male coneheads often sing head down. It has been speculated that the cone helps them penetrate the vegetation beneath when they are disturbed and drop to hide. Nebraska coneheads have medium sized, all black cone undersides.

The remaining 3 species all have continuous buzzes. Most common region-wide is the round-tipped conehead, a katydid of meadows and roadsides.

Listen for a crackling sound in this continuous buzz.

Here the cone is short, round, and has a small black area near the tip.

Here the cone is short, round, and has a small black area near the tip.

Next is the marsh conehead, which so far has turned up only in the marshes of the Indiana Dunes parks.

The sound resembles that of the round-tipped, but comes from a wetland rather than dry upland habitat.

The cone of the marsh conehead may be all green as in this female, or show variable darkness of color.

The cone of the marsh conehead may be all green as in this female, or show variable darkness of color.

For the grand finale, here is the very loud song of the robust conehead:

This can be so loud as to be painful to the ears. It carries for long distances, as you may imagine, and is easy to hear from a car at any speed.

The robust conehead’s cone is unmarked and proportionately short. Any conehead species can come in green or brown.

The robust conehead’s cone is unmarked and proportionately short. Any conehead species can come in green or brown.

The robust conehead is most abundant in areas with dry sandy soils. Its habitat range is fairly broad, from open woodlands to prairies to corn fields.

There are at least two other species which are supposed to occur in the region, but which I have not found. Perhaps next winter I will have recordings of false robust coneheads and slender coneheads to share.

Low Hanging Fruit

by Carl Strang

There haven’t been many new posts in this blog recently because mainly I am going after the low hanging fruit. In other words, most of my research time has been going into checking new counties and new sites, as well as return visits to sites visited earlier in the season, to build my database of singing insect species locations. Though this is productive work, most of that product consists of added locations for common species. That’s not exactly fodder for blogging. A few interesting points have come out, however.

Last week I was working in Indiana. The weather was unseasonably cool, but there was plenty of singing action. In Fulton County I heard a broad-winged bush katydid singing, which establishes that northern species down to the southern edge of the survey region. Clearly they are fewer there than farther north, however. As I drove the rural roads in temperatures that were dropping rapidly to the mid-50’s F, I started hearing a strange, unfamiliar song coming from wetter locations. It was a kind of slow, fluttering buzz, reminiscent of the protean shieldback but much louder, and the buzzes were in repeated short bursts. I pulled off at one such location, and soon realized that these were slightly musical coneheads, their songs altered by the cold, but still singing in lockstep unison. I also found that species in Pulaski County, so they are widely dispersed at least in the northwest Indiana counties.

Slightly musical conehead

Slightly musical conehead

On the way back home I explored some sites in Lake County, Indiana. The best of these was the Hoosier Prairie Nature Preserve. This is a relatively large, high quality prairie and savanna property. Broad-winged bush katydids were abundant there.

A portion of the Hoosier Prairie Nature Preserve

A portion of the Hoosier Prairie Nature Preserve

On the way to Hoosier Prairie I passed a sign with a familiar name.

Tom Sporre Wildlife Area

Tom Sporre Wildlife Area

Tom Sporre was in the Purdue wildlife undergraduate program a year ahead of me. Personable and proficient, he went on to become a prominent Indiana waterfowl biologist who died much too young. I was pleased to see a marsh and prairie set aside under his name.

Singing Insects Range Extensions

by Carl Strang

My other presentation at Saturday’s Wild Things conference reviewed the range extensions by 8 species of singing insects that have turned up in our region in recent years. I ran through them in the chronological order of their discovery, and then offered some general points.

Broad-winged tree cricket (Oecanthus latipennis)

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Map from the Singing Insects of North America website (SINA), 2012. The record in DuPage County resulted from this study, and was added in 2006. Prior to that the species was not supposed to occur in the Chicago region.

Map from the Singing Insects of North America website (SINA), 2012. The record in DuPage County resulted from this study, and was added in 2006. Prior to that the species was not supposed to occur in the Chicago region.

Original range sources: Hebard 1934  (“Northern limits of distribution are Hilliary and Quincy”), McCafferty & Stein 1976 described it as a central and southern species in Indiana, with Tippecanoe County the northern extent. I found them in DuPage County in 2006, and subsequently learned they are abundant throughout the county. They also have reached the junction of the Wisconsin and Mississippi Rivers in Wisconsin.

Jumping bush cricket (Orocharis saltator)

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Jumping bush cricket SINA map, 2012. The added red line indicates the northern range limit as of 1969, when Tom Walker reviewed the genus.

Jumping bush cricket SINA map, 2012. The added red line indicates the northern range limit as of 1969, when Tom Walker reviewed the genus.

Original range sources: Hebard 1934 (Shawneetown northern limit in Illinois; “should however be found throughout southern Illinois as it is known as far north as central Indiana”). McCafferty & Stein 1976 (“known only from the southern two-thirds of the state” with Tippecanoe County given as the northern limit). They are rapidly expanding in DuPage County, abundant in the southern half and spreading into the northern half with new northern limits found annually. I also have heard them at Indiana Dunes State Park.

Roesel’s katydid (Metrioptera roesellii)

Roesel's s-wing female Purdue b

Roesel’s katydid SINA map, 2012. Prior to work by Scott Namestnik and me, the range was thought to end in northeastern Ohio, with a small disjunct area in northeast Illinois. The red dots indicate our added findings in 2012.

Roesel’s katydid SINA map, 2012. Prior to work by Scott Namestnik and me, the range was thought to end in northeastern Ohio, with a small disjunct area in northeast Illinois. The red dots indicate our added findings in 2012.

Original range sources: Roesel’s katydid is a European species that in North America first was found in two suburbs of Montreal, Quebec (Urquhart and Beaudry 1953, Beaudry 1955), and is thought to have been introduced between 1945 and 1951. Vickery (1965), who summarized this history, reported that the species had spread into New York state and Vermont by 1965, and that the long-winged variants that originally had dominated the Montreal population were diminishing in favor of the short-winged forms typical of the European continent. The Montreal population apparently was by then limited by an indigenous parasitic nematode. Roesel’s reached Ithaca, NY, by 1965 (G.K. Morris, as reported by Shapiro 1995), and Long Island by 1990 (Shapiro 1995). Short-winged forms were dominating the St. John, New Brunswick, population by 2008 (McAlpine 2009), and so had arrived some unknown number of years earlier. Nickle (1984) reported finding them in Pennsylvania by the early 1980’s. Roesel’s katydids were collected in two northeastern Illinois counties in the late 1990’s (Eades and Otte, no date). I found them in north central Indiana in 2007, and subsequently Scott Namestnik and I have found them throughout northern Indiana (as far south as Indianapolis) northeast Illinois, and last year the Lower Peninsula of Michigan. Others have added Ohio, Wisconsin and eastern Iowa.

Round-tipped conehead (N. retusus)

Roesel’s katydid SINA map, 2012. Prior to work by Scott Namestnik and me, the range was thought to end in northeastern Ohio, with a small disjunct area in northeast Illinois. The red dots indicate our added findings in 2012.

 

Round-tipped conehead SINA map, 2012. The added red line indicates the northern extent of the range in Illinois in 1934 and in Indiana in 1976.

Round-tipped conehead SINA map, 2012. The added red line indicates the northern extent of the range in Illinois in 1934 and in Indiana in 1976.

Original range sources: Hebard 1934 (“Urbana is a northern limital point”), and McCafferty and Stein (1976) had none north of Indianapolis, but they are so common in northwest Indiana and northeast Illinois now that this is a well advanced range expansion in the intervening decades. I also heard a single singing individual in a meadow at Wyalusing State Park in Wisconsin in 2007.

Handsome trig (Phyllopalpus pulchellus)

Handsome trig 2b

Handsome trig SINA map, 2012. The northern dot at St. Joseph County, Indiana, is the result of Scott Namestnik’s work.

Handsome trig SINA map, 2012. The northern dot at St. Joseph County, Indiana, is the result of Scott Namestnik’s work.

Original range sources: Hebard 1934 (northern limits given as Marion County in Indiana and Monticello in Illinois; “confined to southern and central Illinois”). McCafferty & Stein 1976 indicated a northern extent in Tippecanoe County. In 2009 Scott Namestnik was posting photos of them from St. Joseph County.

Swamp cicada (Tibicen tibicen)

Swamp cicada 4AU 4b

Original range sources: This species was mentioned by Alexander, Pace and Otte in their (1972) Michigan singing insects paper, but they expressed doubt that it was a breeding species in the state. However, a later paper (Marshall, Cooley, Alexander and Moore 1996) reported finding it in extreme southern MI (intensive searching found it only in the southern portions only of the southern tier of counties. They were not willing to say whether this represented a range extension or the species being missed earlier). I first found it in Marshall County, Indiana, and DuPage County, Illinois, in 2010, but suspected I had heard it earlier. They are scattered across the southern half of DuPage.

Slightly musical conehead (N. exiliscanorus)

Slightly musical Max Wet b

Slightly musical conehead SINA map. This does not yet reflect our finding them in Porter and Marshall Counties, Indiana, in 2012.

Slightly musical conehead SINA map. This does not yet reflect our finding them in Porter and Marshall Counties, Indiana, in 2012.

Original range sources: Hebard 1934 (northern limits indicated as Tower Hill in south central Illinois, and New Harmony in Indiana). McCafferty & Stein 1976 (“In Indiana it is known only from heavy thickets and grasses along the Ohio River”). Gideon Ney, Nathan Harness and I, seeking slender coneheads, found this species at the Indiana Dunes National Lakeshore in 2012, and I found it in Marshall County as well.

Marsh conehead (N. palustris)

Slightly musical conehead SINA map. This does not yet reflect our finding them in Porter and Marshall Counties, Indiana, in 2012.

 

Marsh conehead SINA map. This does not yet reflect our finding them in Porter County, Indiana, in 2012.

Marsh conehead SINA map. This does not yet reflect our finding them in Porter County, Indiana, in 2012.

Original range sources: Hebard 1934 (“Lawrenceville and Carbondale are northern and western limits respectively for palustris…It is probably confined to the southern portions of Indiana and Illinois.”). McCafferty & Stein 1976 reported Tippecanoe County as the northern known extent. Ney, Harness and I found this species to be common at Indiana Dunes National Lakeshore and present in the state park.

General Points

Most of these range extensions are from south to north. Exceptions are Roesel’s katydid (east to west) and the broad-winged tree cricket (spreading south as well, according to SINA coordinator Tom Walker).

I do not know whether any other of these species likewise are spreading south or in other directions.

Some of these are clear range expansions, as they are species which were well known at the time of earlier studies, and now have become abundant beyond the range as then drawn: broad-winged tree cricket, jumping bush cricket, Roesel’s katydid, and round-tipped conehead.

The others have a spottier distribution, or may not have been as well known then, and so might have been missed by earlier researchers: handsome trig, swamp cicada, slightly musical conehead, and marsh conehead.

As for the possible connection between these range extensions and climate change, Gonzalez (2012) mentioned a calculation, based on work in Gonzalez et al. (2010), indicating that the region’s climate has undergone a temperature change equivalent to a southward shift in latitude of 100km in the 20th century. This is consistent with the magnitude of many of these observed range changes.

Marsh Conehead

by Carl Strang

My memory of the great marsh at Indiana Dunes State Park was of an extensive, grass dominated wetland. Perhaps it was once, but today it has succeeded to a shrub swamp.

A tower along one of the trails provides an overlook.

A shrub swamp is a valuable habitat, but for my purposes there are relatively few pockets of the grasses that would harbor the greatest diversity of singing insects.

Here is one such pocket along the north edge.

The drought that has dried the wetlands to a large degree no doubt also contributed to the low numbers of katydids and crickets I found in these grassy patches. One individual of interest, however, was a female conehead.

She instinctively trusted her camouflage, which allowed me to approach and catch her.

Not knowing which characteristics were essential and not wanting to kill her unnecessarily (though I did have the necessary permits), I took a series of photos.

The underside of the cone, its shape and its markings, are an important feature in conehead identification.

In many groups of katydids and crickets, ovipositor shape and size also is helpful in identifying females.

Here is the ovipositor of the female I caught.

Habitat also is helpful, in this case the marsh. Only two species of coneheads with unmarked cones are expected in marshes, the marsh conehead and the robust conehead. In this case the pinched, slightly elongate cone and the ovipositor shorter than the length of the femur point to marsh conehead. The only additional feature I should have checked was the insect’s length, a point to keep in mind for the future.

This finding, which seconds the identification of marsh coneheads that the Missouri students and I found at the nearby National Lakeshore, continues to open my eyes to the limitation of past records. Published accounts don’t show marsh coneheads this far north in Indiana. The same was true for slightly musical coneheads. Consequently I did not have either species on my hypothetical list for the region. Do these discoveries represent range extensions, or simply a mismatch between spotty past surveys of spottily distributed species? It may not be possible to say, but I have to be open to the possibility that my hypothetical list likewise may be incomplete for other groups of singing insects.

Maxinkuckee Wetlands

by Carl Strang

Another area near Culver, Indiana that I wanted to check for singing insects was the Maxinkuckee Wetlands, a state conservation area. Much of it I will need to access by kayak on another occasion. My daytime visit did not produce much, but when I returned at night I was pleased to find a population of slightly musical coneheads, which I first had encountered in the previous week at Indiana Dunes National Lakeshore.

Unlike the mole cricket, as mentioned in yesterday’s post, the slightly musical conehead has a buzzing song.

Along the road edge of the property I heard a different conehead, and traced the song to a small oak.

The impressive volume of the song up close was enough to confirm the singer as a robust conehead. The dry habitat and cone free of black markings support the identification.

Maxinkuckee Wetlands is another site calling for continued exploration.

Houghton Lake

by Carl Strang

A priority site in this year’s singing insect survey work was Houghton Lake, a Nature Conservancy property near my home town of Culver, Indiana. The muck, marl and sand soils potentially support communities including wetland crickets and katydids that I have not yet found. Last week I spent an afternoon and evening walking through the site.

The property, named for this lake, is of particular interest as it hosts a population of rare massassauga rattlesnakes.

There are many smaller wet areas on the site, which is a flat postglacial lake plain. It has great botanical as well as zoological biodiversity.

For the most part I found a long list of familiar, common species.

Black-legged meadow katydids, like this female, are expected in wet areas.

As I walked the lanes I heard crickets singing in the pattern of Say’s trigs, but with a more mechanical or buzzing sound quality. I spent some time searching, because I thought they would prove to be a species I had not seen before. This effort was rewarded.

The handsome trig is one of the more beautiful singing insects in the region. They are tiny, around a quarter inch long.

Another unfamiliar sound was a rhythmic “warg warg warg” coming from a couple wet prairie areas. The song’s rhythm was like that of slightly musical coneheads, but that katydid produces a call with a distinctly buzzing quality. A comparison of recordings led me to the northern mole cricket. The mole cricket’s song is a chirp, but so deep that it is not readily characterized as such. Like the handsome trig, this was a species new to my experience. For future monitoring purposes I was pleased at how far their songs carry, and that at least sometimes they can be heard singing in the mid-afternoon.

A few conehead nymphs turned up in sweep net samples.

These probably will prove to be round-tipped coneheads, which mature later than most of their relatives.

An additional interesting insect was a great blue skimmer.

This was only the third individual of this species I have encountered.

Most of the conservative species I’d hoped to find at Houghton Lake eluded me, but I was only able to see part of the site, and I intend to return.

Chasing Coneheads 3: Slightly Musical Conehead

by Carl Strang

After finding all the slender coneheads Gideon needed, we drove around to assess the scope of their distribution at the Indiana Dunes National Lakeshore. They proved to be abundant in the Great Marsh and other places. We heard other familiar singing insects as well. Then we heard a new one at another wetland, unfamiliar to me but well known to the Missouri grad students. We stopped and found one. This was the amusingly named slightly musical conehead.

This marsh katydid has an interrupted song that to my ear has the rhythm and tempo of a snowy tree cricket but with buzzes rather than clear toned chirps.

The slightly musical conehead has the most magnificent cone structure of all the North American species.

The cone is huge, and black on the length of its underside.

To me the most amazing feature of this species is its synchronized singing. All the males in an area sing in unison. When we disturbed the one we were stalking, he paused only for a few seconds and then started up again in rhythm with other males in earshot. “They must sing,” said Gideon, who also shared the information that this species avoids spots that have other conehead species with continuous songs.

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