Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '6f5eeea900fdb021fdcc2430f7855b5d360e538ba3dbdd834a4028446edbdc3f' 
  AND token = 'rAL7EJ36lzl62Cq5WRoC+eYn/wCRbE81t7wH+He5SJk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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