Landcare Research - Manaaki Whenua

Landcare-Research -Manaaki Whenua

Fragilariforma cassieae C.Kilroy & E.A.Bergey

Fragilariforma cassieae

Type slide

CHR 565730, Jordan Stream headwaters (Jordan Saddle, Canterbury, South Island, New Zealand), surface sediment samples from pool, C. Kilroy, 13 November 1999.

Isotypes: BM 101032; BRM Zu 5/43; CAS 221053; NIWA diatom collection, Christchurch, New Zealand (sample/slide #226).

Institution holding the type material


Known distribution

New Zealand: Jordan Saddle, Bealey Spur, Goat Pass, (Arthur's Pass National Park); Lake Hochstetter (Westland); St Arnaud Range (Nelson Lakes); Deceit Peaks, Table Hill, Rakeahua Valley, Little Mt Anglem (Stewart Island).

Australia: Clarence Lagoon, Lake Picone (Tasmania).


Named after Dr Vivienne Cassie Cooper in honour of her outstanding contribution to diatom research in New Zealand.


Valves (6-)11-27 μm long, 6.2-9 μm wide. Girdle view: rectangular. Zig-zag colonies. Plastids small, discoid. Open girdle bands, 3-5, with rows of poroids on edges facing epitheca. Valve view: rhombic with narrow protracted apices, to rhombic with slightly concave sides, to rhombic. Striae 15-18 in 10 μm, distinctly punctate, continuous across valve and mantle, often with narrow break along axial area, sometimes central only. Striae radiate centrally to parallel towards apices. Areolae 26-29 in 10 μm. Rimoportula absent. Marginal spines on interstriae, tapering hollow tubes deflected outwards. Apical spines absent. Apical pore fields, ~40 poroids in longitudinal rows, extending onto valve surface. Mantle plaques often present along mantle margin.

NOTE: description abridged to satisfy publisher's copyright requirements.


Funding from TFBIS (Terrestrial and Freshwater Biodiversity Information System), administered by the New Zealand Department of Conservation, is gratefully acknowledged.


Kilroy C, Sabbe K, Bergey EA, Vyverman W, Lowe R 2003. New species of Fragilariforma (Bacillariophyceae) in New Zealand and Australia. New Zealand Journal of Botany 41: 535-554.