What is "macivera"

Macivera is a genus of extinct vascular plants. Fossils were found in sediments in Bathust Island, Nunavut, Canada, from the upper Silurian ( Ludfordian, around ). The leafless stems (axes) branched dichotomously and were relatively thin, being between 0.7 and 1.0 mm wide. Spore-forming organs or sporangia, which were elliptical, being longer than wide, were borne on the end regions of stems. Macivera is considered to be a zosterophyll.