SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ed235ba2eade00f9142369833f3ae6298cec1b94da62e8c80b703ffd751f19bc' 
  AND token = 'tTs7CcwU59HwRmdQjmxrFFJNshFTjrazQThCcDtQXCU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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