SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd10540ccdd2b5151697f1f573e79e3d39c5d3c0f3fe6d81a483a2a4c360ebb0f' 
  AND token = 'i9RGbdm2ced/NMap4q0P7eC59nDwTPTG0OcyxV9wSec=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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