SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ae7640d696fb0babe173fedc4e674caa7bfcbbad89a215c039f8efd35405a6c' 
  AND token = 'mQkX793Zr/1p0BKrnbsvelDlq2TrKAmBenHZKL0CrJk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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