Marsh Coneheads Illinois

October 26, 2023 at 6:47 am (singing insects)
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by Carl Strang

One of the targets in my plan for this year’s singing insects survey was an area of the Des Plaines Conservation Area in Will County, Illinois, where I hoped to confirm the presence of marsh coneheads (Neoconocephalus palustris). I had found them in marshes of the Indiana dunes area and in Fulton County south of there, but in Illinois they had been documented only in the southernmost part of the state.

A photo posted in iNaturalist last year appeared to be of a marsh conehead. It was accompanied by the claim that this was a slender conehead (N. lyristes), which is historically known from northeast Illinois but which I have been unable to find in the present day. The photo showed a configuration of the insect’s pronotum which ruled out lyristes but was consistent with palustris. Later the photo was withdrawn, but I had noted its location and went there on August 12. Coneheads began singing at dusk in the marsh vegetation, which is expected for palustris but not for lyristes, which reportedly begins to sing in the afternoon. There were enough individuals singing that I was frustrated in my attempt to zero in on one. I returned a few nights later and this time spotted several coneheads in both green and brown body colors. I caught one for photos.

This green male shows the pronotum shape and head-cone profile of a marsh conehead. In lyristes the cone would be longer, and there would be a sharp right-angle bend in the posterior edge of the pronotum.

The underside of this individual’s cone is green. I saw a brown katydid with a darker, more gray color there. That appears in some of the Indiana dunes coneheads, too, but is not the black that would appear on a slender conehead, which also would have a more elongate cone.

At my age I need my electronic devices to hear these coneheads on warmer nights, which was one reason why I failed to find them on the first visit. The cooler second evening helped. While seeking them with my devices I also was hearing one of the less common wetland meadow katydids, and I took some time to catch one for identification. Stripe-faced meadow katydids (Orchelimum concinnum) occur elsewhere in the Des Plaines Conservation Area, and dusky-faced meadow katydids (O. campestre) sing their similar songs in marshes at the adjacent Midewin National Tallgrass Prairie.

These proved to be campestre, which makes sense because this was more of a marsh, where the concinnum were in wet areas of dolomite prairie.

All of this made for one of the most satisfying moments in this year’s fieldwork.

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Landscape Ecology of Singing Insects 2: Human Influences

April 8, 2020 at 6:29 am (ecology, singing insects)
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by Carl Strang

The previous post illustrated that the Chicago region has been a dynamically changing landscape through the recent millennia, but that now is overshadowed by the alterations our own species has made. Burgeoning human numbers have overwhelmed the planet’s ecosystems, and the native habitats described earlier mostly have been replaced by agriculture and urban growth in the Chicago region. One of the more dramatic changes is the loss of the Kankakee wetland, once described as the Everglades of the North. That vast wetland was drained for agriculture, and only a few pockets of it survive in preserves. Much of the Kankakee River in Indiana is now a straight channel with constructed high levee banks. Other smaller wetlands received similar treatment, with drainage ditches spreading across the agricultural portion of the region. This is not universally devastating to wetland species. Northern mole crickets, for instance, occasionally can be found along drainage ditches.

Drainage ditch, upper reaches of the Kankakee River, St. Joseph County, Indiana. Note farm fields on both sides.

Prairie mostly has been replaced by agricultural fields, and fire suppression has led to its invasion by woody plants. Specialists such as the prairie meadow katydid, prairie cicada and short-winged toothpick grasshopper are hard to find.

Prairie meadow katydid

My singing insects research has required a lot of driving to reach the relatively tiny surviving preserves and parks to which many of the species are now restricted. Much management effort is required in these little islands to maintain their habitats. There are exceptions, of course. Many other species have thrived under our influence. These are mainly weedy ones such as the striped ground cricket, short-winged meadow katydid and Carolina grasshopper, which do well in disturbed habitats, along with woodland edge species such as the greater angle-wing, snowy tree cricket, and jumping bush cricket, which can meet their needs in residential neighborhoods dominated by lawns and scattered trees and shrubs.

Jumping bush cricket

Habitat destruction is not the only human influence. Climate change is the probable cause of northward range expansions by several singing insect species, and it likely will lead to the extinction of the sphagnum ground cricket from the region as the sphagnum bogs dry up. Say’s cicada and some northern grasshoppers already appear to be pushed out.

Sphagnum ground cricket

Climate change isn’t simply a matter of rising temperatures, as the term “global warming” may seem to imply. Global warming is an accurate enough term, as the simplest way to measure climate change is to track the global average temperature. But the point is that our changes to the Earth’s thin skin of atmosphere are increasing its held solar energy. That energy alters patterns of atmospheric flow and the behavior of storms. Droughts, more frequent flood-causing rains, and seasonal increases or decreases in temperature that seem abnormal are examples of results we observe locally. The singing insects are forced to adjust as best they can. Droughts force sphagnum ground crickets into the wettest parts of their bogs. The severe drought of 2012 concentrated wetland meadow katydids and marsh coneheads into the small portions of the Great Marsh in the Indiana Dunes National Park that remained wet. Oblong-winged meadow katydids may be pre-adapted to such year-to-year variability. Blatchley (1920) observed that their eggs, laid in moist soil, can take 2-3 years to hatch. In my travels through the region I failed to hear a single individual in the years 2010 and 2019, but in other years they have been abundant and widespread. Some of the cicadas and other species may have similar flexibilities.

Oblong-winged katydid

People also have introduced plant species from other parts of the world which, released from the consumers and competitors which hold them in check in their native lands, have become invasive plants here. Their unfair competitive advantage has led to their displacing the region’s native vegetation in an increasing number of places. This is most evident in our wetlands. Wetland meadow katydids and other singing insects are limited to places where native wetland grasses have not been supplanted by reed canary grass, common reed, purple loosestrife, and hybrid cattails. These invasive plants are proving difficult to control, and the outlook is not good for species such as the dusky-faced meadow katydid and marsh conehead. To my knowledge the once relatively widespread stripe-faced meadow katydid now is confined to a single site, and the slender conehead, never known from many locations, apparently is gone from the region.

Stripe-faced meadow katydid

Introductions have not been limited to plants. Several species of singing insects also have been imported. Roesel’s katydid is the most common of these in our region. A European predaceous katydid, Roesel’s was introduced to the Montreal, Quebec, area several decades ago and expanded from there. They occur in open habitats with tall herbaceous vegetation throughout the Chicago region. Japanese burrowing crickets are thought to have arrived at the port of Mobile and spread out from there. They are abundant as far north as Indianapolis, and common in Rensselaer in the southern part of our region. With scattered new appearances each year occurring as far north as DuPage County in Illinois, so far, I expect them to become widespread and abundant here. The tropical house cricket represents the possibility of other, short-term introductions that are unlikely to persist in our climate.

Roesel’s katydid

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New Sites

November 6, 2019 at 7:03 am (singing insects)
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by Carl Strang

I enjoy going back to places I have visited before as I survey the singing insects of the Chicago region. Some are beautiful, some have the possibility of harboring species I haven’t found there yet. I am finding, however, that the greatest jumps in progress come from visiting new places. Today I wish to mention some of the ones I checked for the first time this year.

Stoutsburg Savanna Nature Preserve

The Stoutsburg Savanna is a state nature preserve in northern Jasper County, Indiana. I realized that I had done nearly all my Jasper County survey work in the Jasper-Pulaski Fish and Wildlife Area, and I needed to look elsewhere. Stoutsburg’s beauty was a pleasant surprise, and I made some nice observations there.

Mottled sand grasshopper, Stoutsburg Savanna

Another new Jasper County site was the combined NIPSCO Savanna and Aukiki Wetlands. Though much of the latter, sadly, has been taken over by reed canary grass and other invasive plants, part of the area remains good quality.

The prairie portion of the site had handsome grasshoppers.

An Aukiki broad-winged bush katydid

I was glad for the opportunity to get a series of photos of this female broad-winged bush katydid.

Another site I had been wanting to see was Wintergreen Woods Nature Preserve, a LaPorte County (Indiana) Conservation Trust property. This was another pleasant place to visit.

Wintergreen Woods provided me with a county record for the clipped-wing grasshopper, a crepitating species.

The best observation at a new site came from the Ruth Kern Nature Preserve, an Acres Land Trust property in Fulton County, Indiana.

An interesting looking katydid peeked at me from a grass leaf.

It proved to be a marsh conehead, the first I have seen outside the Great Marsh of the Indiana Dunes National Lakeshore and Indiana Dunes State Park.

I released the female after taking a series of documenting photos.

The Ruth Kern preserve’s forested trails are pleasant to walk, looping down to the Tippecanoe River.

I look forward to new discoveries in future years at sites I still haven’t explored. It is good to see the work done by governmental and private agencies to protect some of the best wild places.

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Wil’s White Box

September 8, 2016 at 6:29 am (methods, singing insects)
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by Carl Strang

The leading popular singing insects web page is The Songs of Insects, created by Wil Hershberger and Lang Elliott. Lisa Rainsong and Wendy Partridge of Cleveland, who study northern Ohio’s singing insects much the same as I do for the Chicago region, are friends of Wil’s, and we planned a week together here to help further Wil’s expansion of the Songs of Insects project. We succeeded in finding a number of new species which ultimately will be added to that website. Along the way Wil showed us a white box, the portable version he invented to get amazing photos.

Here Lisa tries out the setup as a rightly proud Wil coaches.

Here Lisa tries out the setup as a rightly proud Wil coaches.

I got to try it, too.

This was my best shot of a confused ground cricket. Wil’s more elaborate home setup allows him to get even better exposures.

This was my best shot of a confused ground cricket. Wil’s experience allows him to get even better exposures.

My try with a marsh conehead was even more satisfactory.

My try with a marsh conehead was even more satisfactory.

As an ecologist, I philosophically prefer field shots of the insects in habitat, but I am tempted to create a white box of my own. The device certainly highlights the structure and colors of these creatures. Wil published the plans on line.

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Sound Ideas: Coneheads

February 10, 2014 at 7:11 am (singing insects, Sound Ideas)
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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.

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Singing Insects Range Extensions

February 5, 2013 at 7:30 am (ecology, singing insects)
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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.

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National Lakeshore Wetlands

September 13, 2012 at 6:30 am (ecology, singing insects)
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by Carl Strang

After catching the melodious ground cricket I drove to Pinhook Bog, a part of the Indiana Dunes National Lakeshore that is open to the public only on rare occasions. I hoped to find stripe-faced meadow katydids, but the bog’s public access boardwalk was bordered by little in the way of grasses and sedges. I was gratified, however, by the presence of sphagnum ground crickets.

These were the first I have found in Indiana. I have seen them only at Volo Bog in Illinois.

After lunch I returned to the place where Gideon, Nathan and I caught the marsh coneheads in early August. Gideon had relayed the news that some of the meadow katydids Nathan also had caught there were dusky-faced, one of the conservative species I had yet to find. The lead paid off.

The legs were totally green, unlike those of the familiar black-legged meadow katydid.

I caught a couple individuals to hold for close-ups.

The head of the dusky-faced meadow katydid is amber colored, with fine dots and lines of red-brown.

While wading the tall grasses and sedges I also spotted a different large meadow katydid with green legs and a beautiful yellow-green face.

Unfortunately I only saw the one, and the auto-focus on the camera frustrated my attempts at a clear photo before she flew away. Though blurred, the image provided enough information for identification.

This was another species on my conservative wetland singing insects want list: the delicate meadow katydid. So, what was so special about this place?

View of the edge of the portion of the Great Marsh under discussion.

For one thing, invasive Phragmites was absent, and cattails were limited to a few scattered plants. Grasses and sedges were the dominant plants. Black-legged meadow katydids were very few, and limited to the dry-soil edges of the wetland. The plants and katydids were zoned. Just inland from the water and mud-flat edge was a zone of shorter, finer grasses in which the only singing insects I saw were abundant slender meadow katydids. Then came taller grasses of intermediate coarseness, where the dusky-faced and delicate meadow katydids were, along with a few marsh coneheads.

Female marsh conehead

The soil became progressively less water saturated as the vegetation rings went outward. Next came a zone of very coarse sedges. The only species I saw in there was, surprisingly, a long-tailed meadow katydid (a tiny species dwarfed by the big triangular sedge stems).  Interspersed here were patches of taller grasses which contained more dusky-faced meadow katydids. This area gave me a strong image of good marsh habitat to carry as I continue to search for these insects in other places.

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Where are the Conservatives?

September 4, 2012 at 5:55 am (singing insects)
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by Carl Strang

It should be obvious that this title is not a political reference. In this election year both political conservatives and liberals are easy to find as they loudly and shrilly make their cases against each other, trying to attract voters (hm, reminds me of singing insects for some reason). The conservatives I am concerned about here are some of the wetland species of singing insects, habitat specialists that are found only within narrow ranges of ecological parameters and are sensitive to invasive species and other disruptions. Much of my research this year is focused on finding conservative species from my hypothetical list for the region.

I haven’t had a lot of luck with wetland conservatives. The northern mole cricket was one, but I still have not found them anywhere but Houghton Lake. The marsh conehead was another. We thought we also found slender coneheads at Indiana Dunes National Lakeshore, but Gideon discovered when he returned to his lab that they all were marsh coneheads as well, misleading because they were outside the size range of that species he was familiar with in Missouri.

Gideon also learned that the underside of the cone should be black, not gray as it was on the marsh coneheads we found.

But what about the several species of wetland meadow katydids in genus Orchelimum? Regionally there should be four species I haven’t yet found: dusky-faced, stripe-faced, delicate and nimble meadow katydids all have been elusive. I should have found dusky-faced meadow katydids, at least, because they are described as being common in a wide range of marshes. Instead I am finding lots of black-legged meadow katydids, a marsh species that spills into drier areas adjacent to wetlands.

Black-legged meadow katydid

Black-legs sing so loudly, day and night, that I wonder how earlier researchers heard the other wetland species. I wonder if black-legs have become more abundant, conceivably pushing the others out. Have I not been looking in the right places or in the right way? Is the lack of success this year a consequence of the drought? Certainly it takes some effort this year to get wet feet in the marshes. I will continue to look. Last week at Chain O’Lakes State Park in Illinois I saw a number of Orchelimum nymphs that were relatively plain and green.

This female meadow katydid nymph is recognized as an Orchelimum by the curved ovipositor.

On the other hand, black-legs don’t get their full colors until after they mature.

This newly molted adult male black-legged meadow katydid still has not developed his full coloration.

I will continue to look this year, and hope for better conditions next year.

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Marsh Conehead

August 23, 2012 at 6:14 am (singing insects)
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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.

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Chasing Coneheads 2: Indiana Dunes

August 15, 2012 at 8:31 am (singing insects)
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by Carl Strang

[Note: Gideon later wrote to share his conclusion that the coneheads we collected were in fact marsh coneheads. The individuals in that population are larger than the ones he was familiar with in Missouri, and the strange gray underside of the cone also was misleading. He later found slender coneheads in another part of their range.] Gideon Ney, Nathan Harness and I reconvened at Indiana Dunes National Lakeshore. We set up camp, but then had to wait out a long afternoon rain wondering if it would stop, if an evening’s search would be any good. The rain stopped an hour before dusk, and we set out prepared to wade through tall wet marsh grasses. We stopped at a corner of the Lakeshore’s Great Marsh, and traded stories as the light faded away. We started hearing the shrill buzzes of coneheads, and began to stalk them. Some of the early ones appeared to be marsh coneheads (Neoconocephalus palustris), which Gideon and Nathan had encountered in Missouri. Then we started catching different ones, and Gideon became increasingly excited as he ticked off characteristics, ultimately concluding that these were the long-sought slender coneheads.

Slender coneheads have medium-sized cones with nearly all the underside darkly pigmented. The Nebraska conehead is similarly marked, but occurs in wooded habitat rather than marsh, and has an interrupted rather than a continuous song.

Most of the ones we found were brown rather than green.

They usually sing head down. This one I disturbed, and he froze after changing position.

Nathan also found plenty of meadow katydids to study back in the lab.

Nathan and Gideon inventory their haul.

They took live katydids back to Missouri, so they can record their songs under controlled conditions in the lab and then get detailed DNA and other biochemical analyses to compare to other conehead species.

Ultimately Gideon hopes to collect slender coneheads from several locations. This species is interesting because it occurs in scattered, separated locations from the Atlantic coast to a site in northwest Illinois. How will its population genetics reflect this indication of a storied evolutionary history?

The night had one concluding chapter, which I’ll share in the next post.

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