Armorback Hexfeeder

The armorback hexfeeder has replaced its ancestor in Mason Polar Sea. Capable of greater movements than its ancestor, it possesses a proto-exoskeleton which is partially internalized, providing attachments for new ligaments and such. It has evolved another pair of breathing tubes, allowing it to take in more oxygenated water thus fueling its growth. Crawling along the sea-floor, it filter-feeds on various microbes, especially at night when they sink into the depths.