[2] Nidularia was again circumscribed in 1817 by Swedish mycologist Elias Magnus Fries and his student Johann Nordholm.

In contrast, the peridium of Nidularia have tinted, rigid, spiny, aseptate hyphae that continue into long threads.

The peridium of Mycocalia species is thin, white and short-lasting, while in Nidularia it is somewhat darker in color and more robust.

The peridium has a tomentose surface composed of irregular, spiny hyphae over a more compact wall that later breaks down to expose may brown peridioles within.

[12] Unlike other bird's-nest genera formerly classified in the family Nidulariaceae, the peridioles of the Nidularia are not connected to the fruit body by a funicular cord, but rather lay clumped together in a gelatinous matrix.

The splash mechanism of Nidularia pulvinata discharges peridioles horizontally at speeds ranging from 0.3 to 3.0 meters per second, with ejection distances averaging 8 mm (0.3 in).