This week for Flora and Fauna Friday, ubiquitous and unmistakable we have an energetic little insect: the Two-lined Spittlebug (Prosapia bicincta).
The Two-lined Spittlebug is what’s referred to as a true bug, a member of the order Hemiptera. This clade is the only clade of insects that can be accurately and technically refer to as “bugs”. The Two-lined Spittlebug is a member of the Spittlebug superfamily Cercopoidea, of which there are a dozen or so species within South Carolina. Yet, the Two-lined Spittlebug is by far the most easy to recognize Spittlebug and arguably the most common in suburban environments. It wears a set of oily-black wings, evenly divided by a pair of tangerine bars, above a head, belly, and thorax dipped in a lustrous garnet-red. When poked at, they will leap explosively into the air on powerful legs to take to the sky on sluggish wings.
Two-lined Spittlebugs, like Cicadas and Leafhoppers, make their living drinking plant fluids. Today’s bug prefers turf grass juice as a snot-nosed nymph and Holly liqueur as a refined adult. This gives them a solid niche in suburbia as turf grass is pre-requisite to a yard and nearly every one of those yards has some shape of Holly, be it a feral Yaupon, hedged Chinese Holly, or shade tree American Holly.
What gives Spittlebugs their common name is the way their nymphs feed. Spittlebugs lay their eggs on their preferred larval host. Upon hatching, the nymph latches on and begins to suckle from the vasculature of that plant. However, unlike most insects, Spittlebugs feed from the xylem of the plant rather than the sap filled phloem. The xylem is the layer that carries water and mineral nutrients to the leaves, rather than sugary sap to the roots, its sap is less nutritious. Spittlebugs actually have specialized gut microbes that produce the essential amino acids the xylem lacks. As a result of xylem feeding, the baby Spittlebugs ingest and excrete excessive amounts of water. That water is then frothed up by the bug into a protective ball of foam, which resembles saliva. The foam shields it from predators, sunlight, temperature swings, and the drying air. Throughout spring, the nymphs molt and grow until the adults emerge in summer. These adults lay their eggs and a second brood comes forth in fall.
