These snakeflies have long prothorax, hyaline wings with a distinct pterostigma and a long ovipositor in the females.
12.
In most families there is a structure on the leading edge near the tip of the wing called the pterostigma.
13.
Adults have the fore-and hindwings of equal length, barely petiolate and a long pterostigma that is broader in the hindwing.
14.
The pterostigma ( a single dark spot in the meshwork of the leading edge near the tip of each wing ) is noticeably elongated.
15.
Since the base of the pterostigma is not preserved it is not possible to firmly place the species into " Styporaphidia ".
16.
The functions of the pterostigma are not fully known, but it most probably has an aerodynamic effect and may also have a visual function.
17.
A pterostigma is present or absent, and the wing membrane is densely covered with microtrichia ( macrotrichia present in " Sylvicola " ).
18.
P�rez-de la Fuente and coauthors tentatively placed the species into " Styporaphidia " based on the presence of two crossveins in the pterostigma.
19.
The specimen possesses antennae placed far back on the head, lacks ocelli, a pterostigma without crossvein, all structures found in " Inocellia ".
20.
The head is longer than it is wide and is longer than the prothorax . " Styporaphidia " possesses the primitive feature of two crossveins in the pterostigma.
