SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '050b17d10134ecf9988da6a6985573b06ea099f7c9c825441eb28c972022b6e1' 
  AND token = 'qkZ0cu11/oDJcQq17INuDApqgFolq6dWfMfwJtqAPgg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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