SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b3cab560702a64d5832e7198e0d34ee3927f8597871a6719040739abf152d91d' 
  AND token = 'M77NsUh3kUsoIG8peuGm6ezUwWOjRD1h3pbQ0uiAUAg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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