SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be6c2830028b2a41a583174a83e7b04877c5cf0dde21c9799cc46ea6bede627a' 
  AND token = 'LFhtc+HIctigY1qOpgWAWPxruLPyXowoBAwRw7O59gI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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