diff --git a/birdvisu/annotations/__init__.py b/birdvisu/annotations/__init__.py
index 667572c..ad07088 100644
--- a/birdvisu/annotations/__init__.py
+++ b/birdvisu/annotations/__init__.py
@@ -77,8 +77,14 @@ class AnnotatedTopology:
 			raise ValueError('Annotator fakes its ID!')
 		annotation.annotator_id = ann_id
 		for v in annotation.for_vertex:
+			if v not in self.topology.vertices:
+				print(f'WARNING: vertex not in the topology, skipping. {ann_id=}, {v=}')
+				continue
 			self.vertex_annotators[v].add(ann_id)
 		for e in annotation.for_edge:
+			if e not in self.topology.edges:
+				print(f'WARNING: edge not in the topology, skipping. {ann_id=} {e}')
+				continue
 			self.edge_annotators[e].add(ann_id)
 		if annotation.for_topology is not None:
 			self.global_annotators.add(ann_id)