HOL phase synonym: Crystallolithus rigidus Gaarder, in Heimdal & Gaarder (1980)
Cells covered in heterococcoliths, i.e. coccoliths formed of complex crystals arranged in radial arrays.
This morphotype represents one of three morphotypes (large, intermediate and small) which have been recognised (Kleijne, 1993; Knappertsbusch et al., 1997) and shown to represent discrete taxa (Geisen et al., 2002):
Calcidiscus leptoporus subsp. leptoporus is the intermediate morphotype: coccoliths 5-8 μm; distal shield with 15-30 elements and smoothly curved sutures. The most common form.
Species recorded from: 47°S, 146° 31'E. A. McEldowney, AAD, unpub.
47°S, 151°E. L. Harding, AAD, unpub.
Genus characteristics: Coccoliths (sub-)circular; central area closed or with a narrow opening; distal shield with laevogyral sutures.