A Not-So-Silent Grasshopper

by Carl Strang

Until a couple weeks ago, the grasshoppers that drew my interest belonged to two subfamilies, the band-winged grasshoppers and the stridulating slant-faced grasshoppers. The former have displays in which they rattle their wings in flight (crepitation), and the latter produce sounds by scraping their folded wings with their hind legs (stridulation). There is an additional small subfamily known as the silent slant-faced grasshoppers. Structurally they resemble the stridulating ones in having faces that slant back distinctly from the tips of their heads, but they lack the minute pegs needed to produce the stridulating sounds.

I had encountered one of the members of this non-stridulating subfamily, the clipped-wing grasshopper, a few times in Indiana marshes.

Here is a female I photographed a couple years ago in Fulton County, Indiana. The slanting face is clear, as is the distinctive wing-end profile which gives the species its common name.

Here is a female I photographed a couple years ago in Fulton County, Indiana. The slanting face is clear, as is the distinctive wing-end profile which gives the species its common name.

On a recent visit to the Houghton Lake Nature Conservancy site in Marshall County, Indiana, I encountered a cluster of these insects in a little marsh meadow. I started hearing buzzing sounds, and was surprised to find that these were being produced by male clipped-wing grasshoppers.

One of the Houghton Lake males.

One of the Houghton Lake males.

They were behaving just like band-winged grasshoppers. Sometimes they crepitated when flushed, but they also were producing the rattling sounds in undisturbed display flights. They also can fly without crepitating. Their buzzes had the same loud, crackling quality as, say, a seaside grasshopper from the band-winged subfamily.

Looking back at the literature, I see that Richard Alexander included this subfamily in his list of Michigan singing insects, and so this is no new discovery. I wonder if the few species in this subfamily started out as stridulators that also could crepitate, and over time were selected to emphasize the latter display, then having ruled out stridulation lost the ability to perform it.

 

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Recent Indiana Excursions

by Carl Strang

In recent weeks I have visited a few spots in Lake and Newton Counties, Indiana, for the first time. One site in Gary is a state nature preserve with several interdune swales.

Though there are some patches of invasive wetland plants, more than 95% of the area is in native vegetation.

Though there are some patches of invasive wetland plants, more than 95% of the area is in native vegetation.

I had high hopes for this site, which I thought might have stripe-faced meadow katydids and slender coneheads. On an evening excursion and an afternoon one I built a rather mundane species list. In this rainy year it is possible that the target species are present but widely scattered. I want to get in there again in a year when drier conditions might concentrate the species of interest, and also make a larger portion of the site easily navigable.

Willow Slough Wildlife Area in Newton County is a large and diverse area that I barely have begun to explore for singing insects. One target for this year was a roadside ditch lined with native sedges and grasses.

The ditch proved to have only common singing insects, but there was a remarkable concentration of clipped-wing grasshoppers, a non-singing species I have seen in only one other location. This is a nymph; most were adults at this late point in the season.

The ditch proved to have only common singing insects, but there was a remarkable concentration of clipped-wing grasshoppers, a non-singing species I have seen in only one other location. This is a nymph; most were adults at this late point in the season.

I also checked out some narrow drainage swales along an access road closely bordered by forest.

One non-singing species there was the graceful grasshopper.

One non-singing species there was the graceful grasshopper.

Short-winged meadow katydids were abundant, but the population was unusual in that nearly half the individuals were the long-winged variant.

Short-winged meadow katydids were abundant, but the population was unusual in that nearly half the individuals were the long-winged variant.

I wonder if the narrow, constrained habitat has something to do with the oddity of that population.

 

In Search of the Dusky-faced

by Carl Strang

Last year I recorded an insect song that was much like that of the dusky-faced meadow katydid, at the Bob Kern Natural Area in Fulton County, Indiana. My note from August 31: “I made recording 28 of an interesting meadow katydid that was producing long, loud series of ticks that were irregular but sometimes sort of doubled, followed by a buzz longer than that of a nearby black-leg. It best matches reference recordings of dusky-faced.” A channel too deep and wide for me to cross prevented my getting close enough to see the singer, but I secured a permit to go in there this year. Circumstances delayed me until the last Sunday in September. The marsh has that important quality that seems essential for the rarer wetland meadow katydids: a lack of invasive plants.

The near bog-like soft soil called for hip boots, and slow careful stepping among the bunch grasses and showy Bidens.

The near bog-like soft soil called for hip boots, and slow careful stepping among the bunch grasses and showy Bidens.

I found two grasshoppers of interest. One was a singing species.

This marsh meadow grasshopper had shorter wings than the one I photographed at the magic swale.

This marsh meadow grasshopper had shorter wings than the one I photographed at the magic swale.

The other I thought might belong to the same subfamily, as it had a strongly slanting face.

No question about the head shape.

No question about the head shape.

Later I was glad that I had followed my practice of taking photos of many parts of the grasshopper, from many angles.

Note the oval-shaped area on top of the head in front of the eyes, and the sword-shaped antennae, the basal portion broad and somewhat flattened, the tip more rounded. Those proved to be diagnostic features.

Note the oval-shaped area on top of the head in front of the eyes, and the sword-shaped antennae, the basal portion broad and somewhat flattened, the tip more rounded. Those proved to be diagnostic features.

This was the clipped-wing grasshopper, Metaleptea brevicornis. Note the end of the wing, which gives the species its common name.

This was the clipped-wing grasshopper, Metaleptea brevicornis. Note the end of the wing, which gives the species its common name.

It turns out that this species belongs to a small subfamily, the silent slant-faced grasshoppers: a nice wetland insect, but not a singer. I slogged on across the marsh, but the only meadow katydids were numerous black-legs, a common species. I should try again earlier in the season next year, but I have to consider the possibility that the recorded insect was an aberrant black-leg.

Black-legged meadow katydid (St. James Farm, DuPage County)

Black-legged meadow katydid (St. James Farm, DuPage County)

I headed up to LaPorte County, which I had not surveyed as well as most of the others in my 22-county region. I had visited the Kingsbury Fish and Wildlife Area earlier in the season, and hoped to pick up some county records there from this late date. Indeed I was to end up with 7, but one in particular needs to be related here. One marsh that is adjacent to the Kankakee River has a levee easily walked, so I checked it out, listening with the SongFinder.

The marsh had few invasive wetland plants.

The marsh had few invasive wetland plants.

I heard an unusual meadow katydid song at one point. The buzz was very long, 6 seconds or more, often with long spaces between, and 6 or 7 ticks leading into the buzz. I couldn’t hear it unaided at a distance, but through the SongFinder it was distinctly louder than the songs of nearby short-winged meadow katydids. I slowly moved in closer, needing to be patient and sit still when the singer paused for longer periods, possibly because of my approach.

The location was mundane, a mix of grasses and common forbs, with the insect ultimately proving to be perched on a tall nettle.

The location was mundane, a mix of grasses and common forbs, with the insect ultimately proving to be perched on a tall nettle.

Of all things, it was a dusky-faced meadow katydid.

Of all things, it was a dusky-faced meadow katydid.

In other words, the species I had set out to find in Fulton County showed up in LaPorte County.

This is only the second location I have to date for the species.

This is only the second location I have to date for the species.

I could hear it unaided when I was within 3-5 feet, but the lesson yet again was the necessity of using the SongFinder pitch-lowering hearing aid when searching for these rarer wetland katydids.

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