Left panel: LSS and substructures identification in A3376. Blue colour bar shows the local galaxy density with KNN of photometric members that are part of the cluster. Yellow squares are the spectral members. The identified filaments are represented as red lines, where nodes are indicated as black dots. Green circumference is 5 × R₂₀₀. Magenta contours are eROSITA large-scale X-ray detections in the cluster area. The identified substructures are plotted with different colours. Right panel: RGB cutout of A3376 the central region (0.5 × R₂₀₀, dashed circle ), overlaid their corresponding galaxy cluster candidate members from S1501 (blue open plus symbols), S1505 (red open cross symbols) and the brightest cluster galaxy (BCG, white star) can be found.