As Phycoplast (from Greek Phykos = " Tang ", " seaweed " and plastos = " shaped " ) is a special orientation of microtubules during cell division of the Chlorophyceae, the largest group within the green algae, respectively. For them, the spindle apparatus disintegrates usually perpendicular to the parting plane and forms a new, parallel to the new cell wall of individual cells arranged Microtubulistruktur. Cell division takes place over a breakup rut and it is not created temporary cell plate as a rule.

In contrast, the microtubules at the Streptophytina, so all multicellular plants and the stonewort, arranged perpendicular to the new cell wall. This is called appropriately by the phragmoplast, which builds by the coalescence of the tubules a temporary cell plate, which can be interrupted in the course of cell division the mitotic spindle and dissolves again with the separation of daughter cells. The phragmoplast can be considered to correspond to derived character, which is an apomorphy of Streptophytina and thus justified their summary.