SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd30935c7bc03b94719ebe0c777f0a98424abbc1102f3989c2ed41ac444aba415' 
  AND token = 'IEM7Iz3ZKCG/8U0k0EAgXpay6ozfiBHqdC+UoNq9yPk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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