With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Helike was submerged in BC.
text_B: X. concinna may refer to  :. Xanthoria concinna , a lichenized fungus. Xanthoria concinna. Xanthoria concinna. Xenomigia concinna , a Colombian moth. Xenomigia concinna. Xenomigia concinna
not_related.