With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: The House of Lusignan reigned only during the Renaissance.
text_B: Notagonum angulum is a species of ground beetle in the subfamily Platyninae .. ground beetle. ground beetle. Platyninae. Platyninae. It was described by Darlington in 1952 .
not_related.