SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1032f8e591de4f9ebb665defa4694de5fabaeb5637c2a7055be57c92c4c71a2' 
  AND token = 'Ko0WKu1jJe6EtF6oWBkrpXNATlaV4/pk1EAThdbJ1ew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}