Hystrichostrogylon holohymenium Islam, 1983

Holotype: Islam, 1983, pl.3, fig.4
Paratype: Islam, 1983
Locus typicus: Isle of Sheppey, SE England
Stratum typicum: Early Eocene

Original diagnosis: Islam, 1983, p.238
The cyst is ellipsoidal, skolochorate to proximochorate, biphragmal and camocavate; both phragma chagrinate or mildly reticulate; pericoel almost completely surrounds the endocyst which rests in contact witl the pericyst at either of the polar ends or laterally; processes solid or hollow, gonal and intragonal when distally tri- or bifurcate respectively, all with bifid extremities; Iength of processes inversely varies at the degree of pericoelar separation; paracingulum is slightly helicoidal and may be slightly sunken; paratabulation 3-4", 6", 6c, 6""", 1p, 1"""", xs; the archeopyle is precingular type P which may be large in the pericyst and indistinct in the endocyst.
Dimensions: Holotype: pericyst 86x83 µm, endocyst 55x48 µm, length of processes 2-6 µm, maximum pericoelar separation 32 µm. Range: pericyst length 90(66)47 µm, breadth 64(55)46 µm, endocyst length 45(40)36 µm, breadth 47(37)31 µm, length of processes 2-9 µm, maximum pericoelar separation 35(18)7 µm. Specimens measured 7.

Affinities:
Islam, 1983, p.238: It differs from the other species of the genus in having pericoel surrounding the endocyst.