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Issue: Vol. 730 No. 1: 18 Nov. 2025
Type: Article
Published: 2025-11-18
DOI: 10.11646/phytotaxa.730.1.5
Page range: 75-81
Abstract views: 96
PDF downloaded: 4

Two new Cretaceous species of Sphynctolethus and a new name for ‘Sphynctolethus pacificus’ (Bacillariophyta: Hemiaulaceae)

Science Department, The Natural History Museum, Cromwell Road, London, SW7 5BD, UK
Science Department, The Natural History Museum, Cromwell Road, London, SW7 5BD, UK
Jersey Heritage, Jersey Museum, The Weighbridge, St Helier, Jersey JE2 3NG
fossil Cretaceous Diatom Sphynctolethus Algae

Abstract

Two new Cretaceous species of Sphynctolethus are described: Sphynctolethus harwoodii P.A.Sims & D.M.Williams sp. nov. and S. antarcticus P.Chambers & P.A.Sims sp. nov., both from New Zealand (Campbell Plateau, DSDP 29, site 275). A replaced name is given for the illegitimate name ‘Sphynctolethus pacificus’. While species in the genus possess a suite of characters, a common character appears to be the costate ocellus.

Although that character is shared with other genera, it remains to be seen if it is actually a synapomorphy rather than homoplasious.

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How to Cite

Williams, D.M., Sims, P.A. & Chambers, P. (2025) Two new Cretaceous species of Sphynctolethus and a new name for ‘Sphynctolethus pacificus’ (Bacillariophyta: Hemiaulaceae). Phytotaxa 730 (1): 75–81. https://doi.org/10.11646/phytotaxa.730.1.5