SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1706f44e67b4dd6cbb02d9f11ff8221c9905a55a81dbebda36d2934d7cb1106b' 
  AND token = 'UR2ZayzaqpFI/P24IQmKQTt3R2PZ0KrAyNjZERs7mYU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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