SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c98c0c444a28a2c1a57c8d7caf3b68907234a11b8cd5c5a59bd56e65e969d604' 
  AND token = 'ynyw3XB914QSczWjfHBHOYbkZc5d2lpu9UUauclkFmU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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