SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25f032550ae89f79157761806de44805925c64bf0bc6dd524a9071203448f417' 
  AND token = 'fuTNnSm7O7wp7OXHMYFyyPcRkEsBNoQPbucavGvWxLk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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