SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '03c4aa96bc0f1492bf0f38aaec0d064b01f81cd43da03eaaf0c8b4aeb1f4dce6' 
  AND token = '99QZiIzHi9Q5cSFhe7ibrqCDeabQTNfW8m70V0cbCII=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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