<?php
$str = '<a href="* ******>Анкор</a> http://w...content-available-to-author-only...m.ru/php-beginners/thread2548607.html';
$a = [];
! preg_match_all('~<a[^>]+>.+?</a>|https?://\S+~', $str, $arr) ?
: $a = $arr[0];
/*
Array
(
[0] => <a href="* ******>Анкор</a>
[1] => http://w...content-available-to-author-only...m.ru/php-beginners/thread2548607.html
)
*/
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