Phytosuccivorous

Phytosuccivorous (pronounced fahy-toh-suhk-siv-er-uhs)

The general descriptor of creatures which feed on sap, such as certain sucking insects.

1860s: The construct was phyto- + succi- + -vorous.  Phyto- (pertaining to or derived from plants) was from the Ancient Greek φυτόν (phutón) (plant) and a doublet of -phyte.  Succi- was a combining for of the Latin succus (plural succi) (juice), source also of the Modern English succulent.  In pre-modern medicine, succus & succi were terms for the expressed juice of a plant, extracted for medicinal purposes.  The construct of –vorous was the Latin –vor(us) + -ous.  Vorous was from vorō (I devour, greedily I eat) +‎ -us (the suffix used to form adjectives) and the suffix –vorous was used to form adjectives with the sense of “habitually eating, feeding on”.  The –ous suffix was from the Middle English -ous, from the Old French –ous & -eux, from the Latin -ōsus (full, full of); a doublet of -ose in an unstressed position.  It was used to form adjectives from nouns, to denote possession or presence of a quality in any degree, commonly in abundance.  In chemistry, it has a specific technical application, used in the nomenclature to name chemical compounds in which a specified chemical element has a lower oxidation number than in the equivalent compound whose name ends in the suffix -ic.  For example sulphuric acid (H₂SO₄) has more oxygen atoms per molecule than sulphurous acid (H₂SO₃).  The related forms, used in entomology and the biological sciences include phytosuccivorous, phytosuccivore & phytosuccivory.

Originally described in entomological taxonomy the H. coagulata (later called Homalodisca vitripennis), is a leafhopper from the insect family Cicadellidae.  The surprisingly destructive little bug was later and more mnemonically named the glassy-winged sharpshooter, a not entirely accurate but graphically illustrative description.  Being phytosuccivorous means the insect lives by sucking sap from the plants which make its environment hospitable.  That’s unremarkable but the glassy-winged sharpshooter is one of a number of sap-suckers noted for a still curious aspect of their behavior: They “make it rain” by flinging droplets of pee while feeding on plant juices.  Although the reason the creatures have evolved to do this remains speculative, close observation has allowed biologists to understand the tiny, catapult-like mechanism the sharpshooters use to propel their waste at what turned out to be extraordinary rates of acceleration.

It’d long been known that trees infested with sharpshooters exude a steady pitter-patter of pee and many nature-loving bush-walkers may have probably enjoyed the experience, thinking it a natural climatic phenomenon.  Use of high-speed video capture allowed scientists to observe the process and analysis revealed how the insects release the waste.  Of interest also was that sharpshooters frequently simultaneously “feed & fling”, droplets collecting on a tiny barb called a stylus at the insect’s rear end which, when the droplet reaches a certain weight, induces the stylus to act like spring, the drop flying off the structure as if hurled from a catapult.

In an intriguing example of the complexity of nature often observed at the miniature level, two tiny hairs at the end of the stylus which, by flicking the water at the point of ejection, greatly increase the flinging power (because of the scale, an aspect of design not able to be added to any of the catapults made by humans since antiquity).  As a result, the stylus launches liquid waste with a maximum acceleration 20 times that of Earth’s gravity.  Impressive though that sounds, such findings are not unusual in the physics of very small creatures and it remains uncertain why the pee is flung so far, the current thinking being the sharpshooters try to send it as far as possible lest the sugar-rich fluid attracts predators.  Nor, despite the name, is there any suggestion the sharpshooters are aiming at anywhere or anything in particular, their interest apparently distance rather than direction.  The researchers hope their findings will improve engineering in the field of microfluidics, in which tiny amounts of fluids are manipulated to diagnose disease, sequence DNA, and study cells one at a time.  Already, engineers are experimenting with a design which emulates the sharpshooter's rear end by attaching false eyelashes to an electric motor.

Small though they are, where colonies cluster, the sharpshooters can do serious damage.  The phytosuccivorous pests daily slurp-down and fling-out hundreds of times their body weight and can transmit bacteria that cause diseases in plants and poison the spiders which play a vital role in maintaining insect numbers.  Their technique of feeding and voracious appetite for so many different hosts means the glassy-winged sharpshooters are an effective vector for a number of bacteria which colonizes the creature by forming a biofilm on its mouth-parts.  The infected insect then transmits the disease to additional plants while feeding and even if not susceptible, the newly infected plant becomes a reservoir, holding the bacterium for other sap-suckers to pick up and carry to other plants.  There have been a number of successful attempts at pest management including the use of insecticides, parasitoids (especially wasps) and the impact of naturally occurring pathogens like viruses, bacteria, and fungi, one recently discovered pathogen actually a virus conveniently specific to sharpshooters.  Evidence suggests the most successful approach is the release of broad-spectrum leafhopper parasitoids which reduce the survival rate of the eggs.