August 27, 2014 at 5:49 am (plant-eating insects)
Tags: Dendrotettix quercus, graceful grasshopper, Jasper County, Jasper-Pulaski, Melanoplus bivittatus, Melanoplus gracilis, obscure bird grasshopper, post oak grasshopper, Pulaski County, Round Lake, Schistocerca emarginata, Schistocerca obscura, spotted bird grasshopper, Starke County Indiana, two-striped grasshopper
by Carl Strang
As I mentioned in the last post, grasshoppers pose problems different from other groups of singing insects. First, most of them don’t qualify as singing insects. Second, those that sing seldom do. Surveying them therefore must be on a visual rather than a hearing basis. Finally, even the visual approach isn’t simple. There are a lot of grasshopper species, sometimes distinguished by tiny structural features. A complete series of photos may be needed to assure an identification. You need every view, above, below, from the side, being sure to get good dorsal and lateral views of the end of the abdomen. Band-winged grasshoppers need to be captured and the wings spread. Also, the color of the hind tibia often is important. All of this was the lesson from grasshopper photos I took in Jasper, Pulaski and Starke Counties, Indiana, last week.
Some grasshoppers are relatively large and spectacular. The bird grasshoppers are the largest I have found to date in the region.
This appears to be the obscure bird grasshopper, common in places at the Jasper-Pulaski wildlife area but at or near the north end of its range.
This is a different bird grasshopper from Round Lake conservation area, my best sorting of characters pointing to the spotted or prairie bird grasshopper, Schistocerca emarginata (S. lineata in older references). Note the different colors of the head and tibia, compared to the preceding species.
The remaining grasshoppers I photographed apparently are all in the enormous spur-throated grasshopper group. Their identifications I think are correct, but a few more photos of certain parts of them would have helped.
The graceful grasshopper, Melanoplus gracilis, is the one of these I most likely have right. It lives in moist grassy areas.
This may be a post oak grasshopper, Dendrotettix quercus. I found it in a dry oak savanna. Superficially it resembles the previous, but note the different wings.
After poring through many reference photos, I had to conclude that this was a two-striped grasshopper. If I had looked at its back, I wouldn’t have needed to go to the trouble.
This grasshopper, like the previous one, didn’t give me a dorsal view, but I’m pretty sure it’s another two-striped.
August 26, 2014 at 6:00 am (singing insects)
Tags: Conocephalus strictus, Dichromorpha viridis, Jasper-Pulaski, mottled sand grasshopper, short-winged green grasshopper, Spharagemon collare, straight-lanced meadow katydid
by Carl Strang
The woodland meadow katydids were the highlight of last week’s exploration of Jasper-Pulaski wildlife area in Indiana, as I described in the last post. It was a productive day, and I came out with 16 new county records for singing insects in the two counties. For example, I have not had a lot of success in the past with finding straight-lanced meadow katydids, but turned them up in both counties on Wednesday.
The females of this Conocephalus species have ovipositors longer than their bodies.
Males have cerci with relatively long straight ends beyond the spurs.
Finding singing grasshoppers requires a different methodology from those used for other singing insects. They sing so seldom that they need to be searched out visually. This approach resulted in two species at J-P.
The mottled sand grasshopper is amazingly camouflaged. I found it by flushing it into flight.
As in most of our members of the band-winged grasshopper subfamily, the mottled sand grasshopper has strikingly colored hind wings.
The other singing grasshopper subfamily is the slant-faced stridulator group.
Short-winged green grasshoppers are common at J-P.
The males usually are green on top and brown on the sides, the larger females more completely green.
A final post from this area will focus on a variety of grasshoppers from non-singing subfamilies.
August 25, 2014 at 5:47 am (singing insects)
Tags: Conocephalus nemoralis, Jasper County, Jasper-Pulaski, Pulaski County, Starke County Indiana, woodland meadow katydid
by Carl Strang
Sometimes the solution to a puzzle comes through a tiny clue, accidentally discovered. Why couldn’t I find woodland meadow katydids? For years I had listened for them and looked for them in habitats where they are supposed to occur. References suggested I should be able to hear their distinctive song around woodland edges, but also indicated they are more a southern species with only scattered populations as far north as the 22-county region I am surveying for singing insects.
On Wednesday I traveled to Jasper County, Indiana, and stopped at the western end of the Jasper-Pulaski state wildlife area. I put on the SongFinder, wanting to find short-winged meadow katydids to add to the Jasper County list, but almost immediately heard something odd. It sounded like a striped ground cricket, but perhaps lower in pitch.
The song was coming from the tall herbaceous vegetation around two white oak trees.
I took off the headphones of the pitch-lowering device, and could no longer hear the song. As I continued to listen, I noticed that once in a while one of the quick short buzzes was preceded by a brief stuttering burst of ticks. Thanks to the stereophonic design of the SongFinder, I soon found the singer.
A male woodland meadow katydid!
It’s the only dry-habitat meadow katydid in our area that is brown rather than green. Once I knew that I needed the SongFinder, and what to listen for, I found them in Pulaski County and, the next day, in Starke. At the Round Lake state conservation area I heard males singing, and spotted a female.
Though the ovipositor is slightly curved, the small size as well as the brown color separates this female from all the Orchelimum meadow katydids. Long-tailed meadow katydids can be brown, but have very long straight ovipositors and live in wetlands.
I had held out hope that this would prove to be the one Conocephalus meadow katydid that I could hear unaided, but such is not the case. That was the tiny clue I needed to solve the woodland meadow katydid puzzle.
August 22, 2014 at 5:56 am (botany, dragonflies and damselflies, plant-eating insects, reptiles and amphibians)
Tags: Enallagma geminatum, Hibiscus palustris, Lestes congener, map turtle, Mayslake, Melanoplus bivittatus, skimming bluet, spotted spreadwing, swamp rose mallow, two-striped grasshopper
by Carl Strang
Photos from Mayslake Forest Preserve have been accumulating, so today’s post covers a miscellany. Two of the subjects were additions to the preserve’s species list. I have been there for more than 5 years, so this testifies to the dynamism of that ecosystem.
The two-striped grasshopper is distinctive enough that I should have noticed it before if it were any kind of significant presence.
This view shows how the grasshopper got its name. Notice the bright red tibias.
The other new species was a turtle.
Though this large map turtle was sunning at Mays’ Lake, it’s a short crawl from Trinity Lake, which is much more extensive and would account for my not having observed this critter before.
The remaining photos are of organisms I have seen before at the preserve, but are uncommon.
Swamp rose mallow is hard to miss.
The tiny skimming bluet always is a delight.
The spotted spreadwing, a relatively late-season species, signals that summer is on the wane.
August 20, 2014 at 5:53 am (singing insects)
Tags: common true katydid, Conocephalus fasciatus, Coral Woods, Elizabeth Lake, Forbes's tree cricket, fork-tailed bush katydid, Hickory Grove, Lyons, McHenry County, Oecanthus forbesi, Pterophylla camellifolia, Scudderia furcata, Scudderia texensis, slender meadow katydid, Tanacetum vulgare, tansy, Texas bush katydid
by Carl Strang
On Friday I took a vacation day to check out some sites in McHenry County for their singing insect potential. I saw parts of 4 widely scattered Conservation Areas (their equivalent of Forest Preserves), and picked up 4 county records for my study along the way.
Within minutes of arriving at the first site, Elizabeth Lake, I spotted this bush katydid feeding on a tansy flower head.
The small body size, and the shape of the ovipositor, identified this female as a fork-tailed bush katydid.
That was not one of the county records, but I did pick up two at that site: Forbes’s tree cricket, and slender meadow katydid.
The area with the greatest potential proved to be Hickory Grove-Lyons. These areas are a political oddity. Though the Lyons portion is in Lake County, it is cut off by a bend of the Fox River, and so managed by the McHenry County Conservation District.
A boardwalk leads through a high quality marsh at Hickory Grove. Other marshes and woodlands in this, and the adjacent Lyons area, are priorities for future exploration.
The year’s first Texas bush katydids, which also provided a county record, were singing in that marsh. The fourth county record, common true katydid (which seems oddly uncommon in McHenry), came at a good-looking forested preserve, Coral Woods. I look forward to return visits to some of these sites.
August 18, 2014 at 5:40 am (insects (other))
Tags: dance flies, Empididae, Kline Creek Farm
by Carl Strang
A program had me at Kline Creek Farm early one morning last week. While waiting at the parking lot for others to arrive, I noticed a swarm of small flies engaged in what I took to be a courtship dance. They were in the light at the edge of a tree-cast shadow, and they remained in the vertical plane defined by that edge, within an altitude range of about 5-8 feet, the zone parallel to the ground and around 20 feet long. Each fly followed a roller-coaster or sine-wave flight path, turning around when it reached each end of the zone. They were going too fast to follow easily, and I had no net with me. I took a few photos.
The flies could be seen clearly only when backlit. Each bright dot is a different fly.
The flies in focus in each photo had similar shapes. Here are two examples:
There is a large spot in the middle, and two lines at each side. The shutter speed is 1/1000 second.
Often there were additional projections above and below.
There is a family of flies called dance flies, the Empididae. They are famous in ethological circles for the nuptial gifts offered by males to females. In some species the pattern is regarded as more primitive, and the gift is a prey item. In others the male wraps the prey in silk. At the other end of the spectrum are species in which the male creates a balloon of silk, and this has replaced the prey entirely. Were the photographed flies members of this family? I do not know. Empidids have bulbous thoraxes, which would account for the bright central spot in the photos. The abdomen is thin, and the long central line could be a highlight, with the wings similarly indicated by the lines to each side. The thicker line below could be the dangling long legs, or perhaps the long proboscis that some species of empidids possess, if these were in fact empidids. Whatever they were, they were fascinating to watch. The shadow-edge convention provides a standardized meeting site, reminiscent of hilltopping butterflies. I found the up-and-down motion of the individual flies hypnotic, the experience delightful.
August 4, 2014 at 6:47 am (singing insects)
Tags: confused ground cricket, Eunemobius confusus, Midewin National Tallgrass Prairie, Neoconocephalus robustus, robust conehead
by Carl Strang
This year there seem to be more confused ground crickets than I have noticed before in DuPage and neighboring counties. Furthermore, their habitat range seems broader. Here is a case in point. A couple weeks ago I was paying the year’s first visit to Midewin National Tallgrass Prairie in Will County. Across one of the interior roads from a grove of trees was a meadow undergoing restoration to prairie, and in that meadow edge a confused ground cricket was singing.
This was the opposite of the species’ typical woodland setting.
I moved in closer to see exactly where the cricket was and found, between the bases of the plants, a little pocket of accumulated cottonwood leaves from last year.
This apparently was sufficient microhabitat to suit him.
There have been plenty of other instances of meadows with confused ground crickets in DuPage, Will and Kendall Counties. Almost always there are at least scattered trees nearby. The song is distinctive enough that I don’t think it’s a matter of me missing them in the past. Whether this is a 1-year increase, the result perhaps of favorable winter conditions, remains to be seen. This area is close to the northern range boundary for confused ground crickets, so another possibility is that this is evidence of yet another range expansion from the south.
Confused ground cricket
Another sound-location combination that surprised me happened last week. I was driving home from an evening walk at Danada Forest Preserve when I heard what seemed to be a robust conehead, within 2 miles of my home on a road I frequently drive. I turned around, parked, and found it.
Robust conehead from a previous year
It was indeed a robust conehead, practically deafening at close range and with the typical short cone lacking black coloration. A second male sang nearby. These were far from the only DuPage County population I know about. This was, however, in a section of Butterfield Road that was rebuilt in the past few years, and there has been much landscaping in the median and along both edges. It seems almost certain that the eggs from which these coneheads hatched were carried in on nursery material. I’ll be interested in seeing if a new disjunct population builds in that spot.