Hedriocystis pellucida
Hedriocystis pellucida
Hedriocystis pellucida, bar = 10 µm

Genus Hedriocystis Hertwig & Lesser, 1874

Diagnosis: Cell surrounded by a non-silicious stalked shell; shell hyaline, colorless, with small holes, pores, through which non-branching axopodia radiate; stalk not always distinct, at one species never observed; central nucleus; Schwärmer observed at two species, with one or two flagella.

Type species: Hedriocystis pellucida

Key to the species

 

1Stalk longer than the test

2

Stalk shorter than the test

H. brachypous

2Shell polygonal and/or with clear conical nipples

H. pellucida

Shell circular or ovoid in circumference

H. minor

Hedriocystis pellucida
Hedriocystis brachypous – from Siemensma 1982
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