A fact that entomologists are well aware of, but one that usually comes as a surprise to everybody else, is that most insect species are still unknown to science, and only a relatively small portion of them have been formally named and described. According to recent estimates only about a quarter of currently living species have the distinction of being assigned official, scientific names, and millions (millions!) of species, most of them insects, remain unnamed and unseen. I kind of knew that, but I still did not expect that the very first, very common conehead katydid that I saw during my first visit to Costa Rica, unquestionably the best biologically explored Neotropical country, would turn out to be new to science. And yet it was. I subsequently named it Copiphora hastata, or the Brown-faced Spearbearer, on account of the enormous, spear-like ovipositor, which the females of this species use to lay eggs underneath thick layers of accumulated leaves on the rainforest floor.
Conehead katydids (Tettigoniidae: Copiphorini) are some of the most spectacular insects that one is likely to encounter in a tropical rainforest. They are easily recognizable by the presence of a hypertrophied fastigium of vertex or, in other words, a giant cone on the head. The function of the cone varies from species to species. In forms that live in grasslands, the elongated process on the head helps the animal blend in amongst blades of grass, and such species are some of the best plant mimics among katydids. But in arboreal species, especially those that are found high in the trees of the Central and South American rainforest, the cone is a defensive weapon, quite effectively protecting them from aerial attacks by foliage-gleaning bats (Phyllostomatidae). Thanks to this protection, coneheads are some of the few Neotropical katydids that can afford to produce long, continuous calls, which other katydids tend not to do because of the risk of being detected by hunting bats. The situation is rather different in the rainforests of Asia or Africa – those places lack the foliage-gleaning bats, and most katydids serenade to their hearts’ content, and coneheads there usually exhibit rather reduced cephalic armature.
The diet of coneheads is quite varied – it often includes seeds, fruits, caterpillars, snails, other katydids, and even small lizards. Their mandibles are usually very sharp and powerful, and coneheads don’t hesitate to use them on potential predators, such as the fingers of an entomologist foolish enough to try to catch one. In fact, Costa Rican Rhinoceros Spearbearer (Copiphora rhinoceros) is one the few insect species that I am a little afraid to handle with my bare hands. Regardless, coneheads are still some of my favorite organisms. In Costa Rica, where I have been studying the katydid fauna for many years, I recorded nearly 60 species of coneheads, over a third of them new to science. Later this year I will be visiting Belize, and there is no doubt in my mind that the place will be teaming with spectacular coneheads. I simply can’t wait to see them.