SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '981696efe36ef75fc9bc2ec8c77db50f10fa57e8c76115a6f22afc04e20915a4' 
  AND token = '6YFCFd+PzRZlnmiXHVa4qBU1rsq19ijGzth3nNy6JxY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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