SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9dc52a0efba7a2b261d19c0ff5222912d2cb38e683206d6631bad4d522d3ff8d' 
  AND token = 'gGULhHAvZNA03wkZktjqyuQcSki1TxJhu7Y/eBgplVU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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