Complex sentence: The two veins in "C. disjunctus" fuse near the apex of the wing forming a single vein before the wing edge, however in "C. wehri" the two veins do not fuse and stay separate the whole length of the wing.
Split into simpler sentences: The two veins in "C. disjunctus" fuse near the apex of the wing forming a single vein before the wing edge. However, in "C. wehri", the two veins do not fuse and stay separate the whole length of the wing.