SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3dc645781bcd3c9abc79d30ec2bf8d6c6e462ee74009d9dc408af0c7f2c14a0e' 
  AND token = '+owc7tJSFir9Y18Au3Hqt2KvI0i5GtIwvsyQucLG1KQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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