SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62849da18b85dccd1a13101f9e499f755a2abb7527f6c8acb138324dc994510a' 
  AND token = 'pxCkL6HGiNmSgr7/E8WNHre71HgJlfGFYuF4pZKswZU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00066

JSON explain

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