Most likely the reason is in non-continuous texture coordinates. In texcoords dump you have the following coordinates:
(CGPoint) 0x34b0b28 = (x=1.00390625, y=0)
(CGPoint) 0x34b0b30 = (x=0.005859375, y=1)
It means that between these two points texture is mapped from 1 to 0 (in reverse direction). You should continue texcoords after 1.00390625 => 1.005859375 => ... Also, your texture must have power-of-two size and must be set up with REPEAT mode.
If your texture is in atlas and you cannot set REPEAT mode, you may try to clamp texcoords to [0; 1] range and place two edge points with x=1
and x=0
in the same position.
And, at last, if your texture doesn't change in x-axis you may set x = 0.5
for all points.