From sur- + stylar.
surstylar (not comparable)
- Relating to a surstylus
2015 November 19, “Neotropical Copestylum Macquart (Diptera: Syrphidae) Breeding in Fruits and Flowers, Including 7 New Species”, in PLOS ONE[1], →DOI:Legend: ah, aedeagal hood; ce, cercus; sa, surstylar apodeme; sl, superior lobe; su, surstylus.