Key to the species related to Synapion (Giustiapion) benedikti

1 Epifrons with a broad furrow between eyes. Pronotum with prescutellar fovea long, ranging from base to apical third or fourth, in basal third broad and deep then thin and finely impressed, distally scratch-like; disc densely and deeply punctured; the largest punctures, in the middle of the disc, mostly 23–38 μm in diameter.............................................. 2

- Epifrons with a thin scratch-like furrow between eyes, sometimes barely visible or absent. Pronotum with prescutellar fovea short and thin, occupying basal third or fourth of pronotum, often reduced to a faint scratch-like furrow; disc densely, but shallowly punctured; the largest punctures, in the middle of the disc, mostly 13-22 μm in diameter. Rostrum length/mesorostrum width ratio: ♁ 5.38–6.38 [6.02], ♀ 6.25–7.81 [7.14]. Distribution: Algeria ... S. perraudieri (Desbrochers des Loges, 1884)

2 Pronotum mostly slightly longer than wide, rarely imperceptibly transverse (pronotum length/width ratio: ♁ 0.97–1.08 [1.04], ♀ 1.00–1.10 [1.06]); densely and deeply punctured with punctures, in the middle of the disc, mostly separated by a distance less than their diameter; interspaces of punctures convex. Body vestiture composed of piliform scales that extend beyond the edges of setiferous pores. Rostrum length/mesorostrum width ratio: ♁ 5.77–7.21 [6.24], ♀ 6.21–7.08 [6.80]. Male and female terminalia as in Figs 27–28, 34–38, 44–49. Distribution: Italy .......................... S. falzonii (Schatzmayr, 1922)

- Pronotum mostly isodiametric or imperceptibly transverse, rarely longer than wide (pronotum length/width ratio: ♁ 0.95–1.04 [1.00], ♀ 0.94–1.03 [0.99]); densely, but less deeply punctured with punctures, in the middle of the disc, separated by a distance equal to or slightly less than their diameter; interspaces of punctures flat or slightly convex. Body vestiture barely visible, composed of microscopic piliform scales that hardly extend beyond the edges of setiferous pores. Rostrum length/mesorostrum width ratio: ♁ 5.50–6.64 [6.09], ♀ 6.64–7.00 [6.74]. Male and female terminalia as in Figs 21–22, 29–33, 39–43. Distribution: Albania, Greece ............................................... S. benedikti Giusto, Košťál and Holecová, n. sp .