When the average person thinks of katydids, which isn’t very often, they likely have in mind the true katydid, Pterophylla camellifolia. A species that is scarce and apparently recently arrived on the Vineyard, it’s widespread now in mainland southern New England and everywhere to the south. A large and robust insect, it produces a correspondingly impressive call.
But for true katydid enthusiasts (yes, we exist!), Pterophylla is just one species among many. Close to 250 species of katydids inhabit North America. And in most places, including on the Vineyard, the bulk of katydid diversity and numbers occur in the form of smaller, quieter, and generally less conspicuous insects.
So I’d like to give a shout-out to the members of the genus Conocephalus. These are modest insects, their bodies ranging from a half-inch or so up to about twice that length, and their songs generally taking of the form of a breathy, sputtering whiz. But they are plentiful, sometimes occurring by the thousands in fields that offer the conditions these insects prefer. And they are diverse, with at least four members of this genus occurring on the Vineyard.
Conocephalus could be an identification nightmare. All the members of this genus are small, long-legged, and green (a few also occur in brown forms), and on a hasty look, there is little to help an observer distinguish among the species. Happily, though, these small katydids have characteristics that actually make them relatively easy to identify. (Easy, that is, once you actually find one; they are masters of concealment.)
For one thing, wing length varies among species. Of the Conocephalus species known to occur on the Vineyard, one (slender meadow katydid) invariably possesses long wings, extending out past the tip of the abdomen. Two others (short-winged and saltmarsh meadow katydids) possess short wings, which vary in length a bit from individual to individual, but basically extend about halfway down the abdomen. And our fourth species (straight-lanced meadow katydid) never shows more than stubby little winglets. Right away, then, a decent look is usually enough to tell what species you’re looking at.
But wait, there’s more! Katydids in general tend to be equipped with reproductive structures that are highly distinctive. On females, this means the ovipositor: An organ extending back from the end of the abdomen and used for inserting eggs into plant stems or seedheads. On female short-winged and saltmarsh meadow katydids, the ovipositor is much shorter than the length of the insect’s body. On a female slender meadow katydid, it’s about the length of the abdomen. And a female straight-lanced meadow katydid possesses a magnificent, bladelike ovipositor that is longer than the rest of the insect’s body.
On males, the key organs are the cerci (“cercus” is the singular), a pair of small spikes protruding backward near the tip of the abdomen. These are not always easy to get a good look at, but when seen, they are distinctive in shape and color, and can serve to clinch the identification of a male meadow katydid with 100 percent certainty.
An outlier among our Conocephalus is the saltmarsh meadow katydid, which, as its common name suggests, is a habitat specialist associated with spartina grass in saltmarshes. Our other three meadow katydids are generalists, occurring in a wide range of grassy habitats. Pretty much any field on the Vineyard has at least one of these species living in it, and once you develop the knack of spotting these discreet insects as they jump, you will realize that the world is full of meadow katydids.