You can use:
strpos to find out if the name has dot (.) 
array_filter to filter the array before iterating in the foreach 
basename to get only the file name 
It would look something like:
<?php
$arquivos = array_filter(glob('*'), function ($path) {
    return strpos(basename($path), '.') === false;
});
foreach ($arquivos as $arquivo) {
    echo "$arquivo<br>";
}
Got it wrong, I removed this part:
You can use the pathinfo thus:
<?php
$arquivos = glob("*");
foreach ($arquivos as $arquivo) {
    $arquivo = pathinfo($arquivo, PATHINFO_FILENAME);
    echo "$arquivo<br>";
}