Lejeunia aechmophora Benedek, 1972; Emendation: Benedek and Sarjeant, 1981, p.340–341, as Gerlachidium aechmophorum.

NOW Gerlachidium. Originally Lejeunia (generic name illegitimate), subsequently Wilsonidium?, thirdly Lejeunecysta, fourthly (and now) Gerlachidium.
Following I.C.N. Article 55.1, the species name Lejeunia aechmophora is validly published even though the generic name Lejeunia is illegitimate.

Holotype: Benedek, 1972, pl.5, fig.7; text-fig.17; Benedek and Sarjeant, 1981, figs.7,9, nos.1–2; Fensome et al., 1993a, figs.1–2 — p.887.
Paratype: Benedek, 1972
Locus typicus: Tönisberg, Niederrhein, Germany
Stratum typicum: Middle-Late Oligocene
Translation Benedek, 1972: LPP

Original description: Benedek, 1972, p. 41
Diagnosis: A Lejeunia species with a smooth shell, which is locally set with smaller or larger spines, as well as bundles of spines. The broad, circular girdle furrow and the especially broad longitudinal field are delimited by edges of small teeth.
Description: The clearly bilaterally symmetrical, pentagonal shell has a thin, smooth membrane, which may be locally set with spines and small spinous processes. The circular, relatively broad girdle-furrow is indented, and is delimited on both sides by an edge of small teeth. The triangular epitheca runs into a small, pointed, apical horn, which is sometimes also set with spinous processes. The trapezoidal hypotheca ends in two broad, but distally streched, pointed antapical horns.
Dimensions: Shell length 66 (57-73) µm, width 60 (52-66) µm, processes appr. 8-12 µm, apical horn appr. 5-6 µm.