What's the noun for foramina? Here's the word you're looking for.
foraminifer
Any of several large aquaticamoeboidprotists, of the subphylum Foraminifera, characterized by streaming granular ectoplasm that among other things is used for catching food, often with a calcareousshell with many holes through which pseudopodia protrude.
“The foraminifer multiplies by fission, or by a process of budding.”
“Miliolidsdominate benthic foraminifer assemblages reflect decreased circulation and probably reduced oxygen contents or euryhaline conditions.”
“From piston cores we know that periods of strong heat influx to the arctic realm are characterized by high foraminifer content in Norwegian Sea sediments.”
“For example, the pink sands of Bermuda get their color from the shells of a foraminiferan called Homotrema rubrum which has pink to red-colored shells.”
“They are acting as 'place markers,' highlighting a rare species of 'tree' foraminiferan named Notodendrodes antarctikos.”
“It contains a large number of mostly amoeboid organisms, including such significant groups as the radiolarians and foraminiferans.”
“Limestones of the underlying carbonate ramp sediments are primarily packstones containing numerous foraminiferans but they do not contain decapod fossils.”
“Thus, although mollusks and foraminiferans of the area have been studied extensively, additional collecting is necessary to fully describe the brachyuran fauna.”