Contraparallels have had their effectiveness proven by Mundane Astrology, even though most astrologers today ignore them.
They have the same effect as the parallel, with no connotation of malefic coming from the prefix contra.
They occur when two bodies are at the same ecliptic latitude, but one to the north and the other to the south.
They should be avoided, given how little ecliptic latitude varies.
They occur when two bodies are at the same declination, but one to the north and the other to the south.