Spissistilus festinus

The species was first described by Thomas Say in a publication dated 1830 as Membracis festina. It was later transferred to the genus Stictocephala as S. festina, and then to the genus Spissistilus, of which it is the type species. == Morphology ==

S. festinus is about 6-7mm long in adulthood, with a pronotum that spans to the tip of the abdomen. The species common name references the shape of the pronotum; the presence of three corners, one at the apex, and one at each shoulder, produces a "threecornered" appearance when viewed from the front. Live adult species are a light green colour; when dried and pinned, species appear deep orange to straw coloured. Adult males are distinguishable from females based on a starkly smaller body size, as well as a red tint on the dorsal side of the pronotum. == Life cycle ==

S. festinus has a hemimetabolous life cycle that includes three stages: egg, nymph and adult. The number of eggs laid per slit is also dependent on the host plant species. The first and second instars of S. festinus is 1.6mm and 2.1mm in length respectively, and develop a series of spurs along the length of the spine. The third instar is 2.9mm in length, and transitions from pale green or straw-like in colour to a darker yellow-brown with green markings. The first three instars typically last 3–5 days each. The fourth and fifth instars last 4–8 days each, and develop more pronounced wingpads, spurs, and pronotum, and grow progressively greener. Across instars 3–5, the dorsal spurs grow more prominent, and mobility increases significantly compared to instars 1 and 2. Females mate soon after they reach sexual maturity around 7–14 days in adulthood. Males will die off quickly following mating, but females will live for about another 38.6 days. The reproductive period of females lasts about 38 days, where a female can produce more than 220 eggs, carrying 21–30 eggs in her ovaries at a time. == Plant hosts ==

S. festinus have been found to use a wide variety of plant hosts. Plant species in the family Fabaceae seem to be favoured for reproduction and feeding, Typical hosts include alfalfa, peanuts, and soybeans == Feeding and diet ==

S. festinus is a phloem feeder with distinct feeding behaviours. Using its piercing and sucking mouth parts, S. festinus probes petioles and shoots to obtain phloem sap, as well as create a series of lateral punctures around the stem of its host plant. == Defensive behaviours ==

S. festinus nymphs have been observed to produce a globule from the abdomen as a defense mechanism, paired with retreat to another sector of the stem. == Economic importance ==

Damage to plant hosts The reproductive and feeding habits of S. festinus cause significant damage to its different plant hosts, which led them to gain notoriety as pests. Mainly intermediate and final instars cause damage by puncturing to the petioles and shoots of different plants while feeding, which causes girdling. It then reaches the salivary glands, which connect to the salivary canal, where it can then be transmitted to healthy plants when S. festinus feed. Biological control Studies on S. festinus susceptibility to predation as a tool for population control in crop systems have been of interest over the years. Specific combinations of predator species and instar level of S. festinus have been found to determine mortality rates. Larvae of Chrysoperla rufilabris commonly known as "red-lipped green lacewing", have been found to show mortality to all instars of S. festinus. N. roseipennis have been found to prey on all life stages of S. festinus. == References ==