Wild Side: Patience, diligence trump assumptions

Wild Side: Patience, diligence trump assumptions

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The insect is probably Nomotettix cristatus, northern crested pygmy grasshopper, but the author does not know for sure, and may not be able to find out. — Matt Pelikan

Times have never been better for the amateur naturalist. Excellent field guides keep coming out, addressing harder and harder groups of organisms. Internet sources like Bugguide.net provide vast catalogs of indentified photos to compare a subject to. Digital photography has greatly simplified the process of capturing a good image of what you find. And a vast network of helpful experts is getting steadily easier to tap into.

But the study of natural history remains endlessly challenging. Sometimes you bang up against a genuine gap in knowledge — nobody may know, for example, how to tell the members of a fly genus apart without dissecting specimens. Other times, the knowledge is out there, but the subject is so obscure that you can’t find it. But most often, your own ignorance and wrong assumptions lead you astray. The study of nature has a built-in measure of frustration.

I’m wrangling with a good example of this, and the history of my relationship with the organism in question illustrates how the study of nature often goes (or doesn’t go). The story starts about a dozen years ago, when I first noticed some type of tiny hopping insect along the fire lanes of Manuel F. Correllus State Forest in early spring. Perhaps three-eighths of an inch long at most, these grayish mystery critters were perfectly camouflaged against the sand: I usually noticed them only when they jumped, and then my eyes simply couldn’t follow them. Unable to get a decent look, I had no idea what they might be.

Over time, after catching glimpses of dozens of these mystery insects, a vague impression of their appearance evolved. Stout and seemingly arched along the center line of their backs, they aligned most readily with my mental image of a leaf-hopper. So I perused photos of leaf-hoppers, hoping in vain for a match that might at least be close enough to point me to toward some subset of this vast family (it has more than 20,000 members worldwide).

Barking up this very wrong tree might have been the end of the story if one of these critters hadn’t landed, coincidentally, almost under my nose as I was photographing something else. Finally getting a decent look, and even a poor but possibly helpful photograph, I realized I was actually seeing a grasshopper, wholly unrelated to the leaf-hopper I had surmised. Grasshoppers I know at least a little about, so this seemed like progress!

But again, I bungled. Such a tiny grasshopper must be an immature nymph, right? And to be active early in mid-April, such a nymph would have to belong to a species that either overwinters as nymph, or hatches very early in the season, right? These seemingly reasonable assumptions had me searching for a match among photos of band-winged grasshoppers, a large grasshopper family that contains all the species I know of that are active in early spring on the Vineyard.

Meanwhile, I posted my bad photo on various websites and Facebook groups, seeking assistance putting a name to the beast. Shortly, I received a response that didn’t provide an identification, but at least revealed the flaws of my thinking: the insect wasn’t a nymph at all, but rather an adult member of a group called the pygmy grasshoppers. Aptly named, these tiny grasshoppers overwinter in their adult stage, a behavior I had never heard of among grasshoppers and therefore hadn’t even considered. And it had never occurred to me that there might be pygmy grasshoppers on the Vineyard.

With a gradually developing sense of what to look for and where to look for it, I finally managed to spot a few of these insects before they disappeared, and then, stealthily, I closed in for some better pictures of one in the moments before it bounded away, its powerful legs making an audible “snap” as it took off. The photos revealed an odd but distinctive design: as on most pygmy grasshoppers, the exoskeleton of the thorax extends backward to the insect’s tail end (the beast lacks visible wings). And along the center line of this extension of the thorax runs a raised and serrated ridge.

At present, I think these traits narrow this insect down to the genus Nomotettix. It’s probably the species cristatus, sometimes known as the northern crested pygmy grasshopper. I’ve sent my photos out to a couple of experts hoping to either confirm this, or else correct my latest error! But I’m prepared to learn that my photos aren’t sufficient to tell what species it is. In any case, the experience has been a useful reminder of how much patience matters to a naturalist, as you navigate a winding path through incomplete knowledge and false assumptions.