If you use parentheses in the separator given to split, the captured string will also be part of the resulting array. See this example:

use strict;
use warnings;
use Data::Dumper;

my $file = "start<<<<part2>>>>middle<<<<part3>>>>end";
my @parts = split /<<<<(.+?)>>>>/, $file;
print Dumper \@parts;
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which results in

$VAR1 = [
          'start',
          'part2',
          'middle',
          'part3',
          'end'
        ];
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and gives you the content for your splitted files and the names in alternation.