SELECT 
  1 
FROM 
  q_lock_keys 
WHERE 
  key_id = '67e8976aa92563b316d5018c4c1240970786eb5cf6a44447b5754db295e88a2a' 
  AND token = 'q7/yZXQUJoOXiCyPoztSKVdhmeaEGb7wEZOv5GBm61A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}