Wil’s White Box

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

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.

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.

National Lakeshore Wetlands

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.

Where are the Conservatives?

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.

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.

Chasing Coneheads 2: Indiana Dunes

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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