SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a58fe7f8753ddf949e6b75436b847a028812cd548b7ec680a9674af846e80ad' 
  AND token = 'ajRZWCj7QTsu+jX6q2MwQ62mjU4Ssly2sGqksQLKSOA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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