diff --git a/src/flight/query.cpp b/src/flight/query.cpp
index 56034e9..4baeb67 100644
--- a/src/flight/query.cpp
+++ b/src/flight/query.cpp
@@ -46,11 +46,15 @@ std::string assemble(const std::vector<std::pair<std::string, std::string>>& cla
 // ---------------------------------------------------------------------------
 
 QueryTopicBuilder& QueryTopicBuilder::withName(const std::string& name) {
-  clauses_.emplace_back("locator", opEq(name));
+  // The server's name/identity filter key is "name". It was "locator" until
+  // mosaicod #565 renamed it; a stale "locator" key silently matches nothing
+  // against current servers. (The streaming ticket descriptor still uses
+  // "resource_locator" — only the query filter key changed.)
+  clauses_.emplace_back("name", opEq(name));
   return *this;
 }
 QueryTopicBuilder& QueryTopicBuilder::withNameMatch(const std::string& partial) {
-  clauses_.emplace_back("locator", opMatch(partial));
+  clauses_.emplace_back("name", opMatch(partial));
   return *this;
 }
 QueryTopicBuilder& QueryTopicBuilder::withOntologyTag(const std::string& tag) {
@@ -74,11 +78,13 @@ QueryFilter QueryTopicBuilder::build() const {
 // ---------------------------------------------------------------------------
 
 QuerySequenceBuilder& QuerySequenceBuilder::withName(const std::string& name) {
-  clauses_.emplace_back("locator", opEq(name));
+  // See QueryTopicBuilder::withName — server key renamed "locator" -> "name"
+  // (mosaicod #565).
+  clauses_.emplace_back("name", opEq(name));
   return *this;
 }
 QuerySequenceBuilder& QuerySequenceBuilder::withNameMatch(const std::string& partial) {
-  clauses_.emplace_back("locator", opMatch(partial));
+  clauses_.emplace_back("name", opMatch(partial));
   return *this;
 }
 QuerySequenceBuilder& QuerySequenceBuilder::withCreatedAfter(int64_t ns) {
diff --git a/src/flight/query.hpp b/src/flight/query.hpp
index a4f0bc6..ee4508c 100644
--- a/src/flight/query.hpp
+++ b/src/flight/query.hpp
@@ -18,7 +18,7 @@ namespace mosaico {
 // `body_json` is a pre-rendered JSON object (no outer braces quoting issues).
 struct QueryFilter {
   std::string name;
-  std::string body_json;  // serialized object, e.g. {"locator":{"$eq":"x"}}
+  std::string body_json;  // serialized object, e.g. {"name":{"$eq":"x"}}
 };
 
 // Per-topic result entry.
@@ -41,9 +41,9 @@ struct QueryResponse {
 // Fluent builder for QueryTopic filters.
 class QueryTopicBuilder {
  public:
-  // Exact match: {"locator": {"$eq": "<name>"}}
+  // Exact match: {"name": {"$eq": "<name>"}}
   QueryTopicBuilder& withName(const std::string& name);
-  // Partial match: {"locator": {"$match": "<substring>"}}
+  // Partial match: {"name": {"$match": "<substring>"}}
   QueryTopicBuilder& withNameMatch(const std::string& partial);
   // Exact tag: {"ontology_tag": {"$eq": "<tag>"}}
   QueryTopicBuilder& withOntologyTag(const std::string& tag);