SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c45d9ebd991368845ef9f650e0f80f2e797017a2c327721743e6f86363cb9c42' 
  AND token = 'VAtuKW00KuiRJOGTbsBjsiz2hL1M/Lf6ymGZ5AngaXs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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