SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2f0b73a69a7f3c3232b3c06ad4b960a125b1def6861e188b6201472c1eeb6fb9' 
  AND token = 'pjlGe11qzMDp7p+t47W2R2/oEumbOj9guenduw342lU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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