SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0916ea1352ebecf2a5ba3110903b7bb6bc181740d1b21c32df36de91d1fd80e2' 
  AND token = '+GGjQQjY7KIoC8pxm9zqDvyLwsh2n8DZGafdADpBDvc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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