SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e8eb421489bf6a06230c3448fa6fea65022de883a5d9faa103358f24404170aa' 
  AND token = 'YwrcRVrT9fBzI0JzZ3Lk3GT1H+MUFcjgBLtBHkw9PyU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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