A new secondary sex character, here named the ‘tibial gland’, found on the forelegs of the males of a new spittlebug species, Augustohahnia dilatitibia sp. nov. (Hemiptera: Cercopidae) from New Guinea, is reported for the first time. The males of Augustohahnia dilatitibia sp. nov. are very distinct and unusual in having remarkably swollen fore tibiae with flat, bare and smooth prolateral surfaces. Scanning electron microscope observations revealed that the prolateral surface of the swollen fore tibiae is covered with numerous, very fine pores, with a density of 0.0068–0.0076 pores/μm2. The distance between the pores varies between 4.04 and 10.77μm. Each pore unit is composed of a deep cavity in which one central sponge-like, grooved disc is set. The opening of the cavity is c. 5.20–5.78 μm in diameter. The central, sponge-like disc in the cavity has a sponge-like apex with 55–65 longitudinal grooves and measures 4.34–4.55 μm in diameter. There are also one to three fine, nearly ellipsoidal pits (c. 0.35–0.48 μm wide and 0.62–0.85 μm long) on the marginal cuticle rim surrounding the central sponge-like disc. These pores are presumed to be male pheromone-producing glands. If so, this represents the first report of a possible male pheromone structure in cercopid spittlebugs. Two new species of the spittlebug genus Augustohahnia Schmidt (Hemiptera: Cercopoidea), A. dilatitibia sp. nov. and A. sanguinifrons sp. nov., both from New Guinea, are described and illustrated. A key to the four known species in Augustohahnia is provided.

Feeding dynamics in the spittlebug Philaenus spumarius were analysed to determine the food source. Evidence from previous reports indicates that this species and similar insects feed from the xylem. However, it is not clear whether they extract sap from the main transpiration stream, or from some subsidiary compartment of xylem, such as immature or cavitated vessels. In feeding from such subsidiary compartments, the insects could avoid the large hydraulic tensions thought to prevail in xylem on the main transpiration stream. Philaenus, for example, is shown here to initiate feeding, and to feed rapidly, from plants in which the full xylem tension is estimated at −10 bar. From measurements of feeding rates and feeding patterns in stressed and unstressed plants, it is shown that Philaenus cannot feed from subsidiary xylem compartments. It is concluded that this insect feeds directly from the main transpiration stream, and at the full hydraulic tension which prevails there. The anatomy of the feeding pump in Philaenus appears consistent with this conclusion. Spittlebugs therefore offer an experimental tool for quasi- non-invasive sampling of the transpiration stream.