University Of Tasmania

File(s) under permanent embargo

Dimorphism in the Antarctic cryptophyte Geminigera cryophila (Cryptophyceae)

journal contribution
posted on 2023-05-20, 21:40 authored by van den Hoff, J, Bell, E, Whittock, L

A pink to red‐pigmented cryptophyte of undetermined taxonomic affinity was isolated and cloned from two seasonally ice‐covered. meromictic, saline Antarctic aquatic environments: Bayly Bay (BB) and Ace Lake (AL). The clones shared a number of morphological and ultrastructural similarities with other cryptomonad genera, which confounded identification by light and electron microscopy. Cellular pigments extracted from the AL clone showed an absorption maximum corresponding to the biliprotein Cr‐phycoerythrin 545, thus narrowing its potential taxonomic affinities. Partial 18S SSU ribosomal gene sequences were isolated from both the AL and the BB cryptomonads’ nuclear rDNA, whereas PCR‐amplified and their molecular phylogenies inferred from the subject sequences. Our results, and the results of another study that used our prepublished sequence data, invariably resolved both clones as very close matches with the Antarctic cryptophyte, Geminigera cryophila. When combined, the morphological, chemical, and molecular evidence suggested that both of our cryptophyte clones were a cryptomorph of the G. cryophila campylomorph. Slight differences between the AL and BB nuclear tree reconstructions suggested divergent microevolution following long‐term isolation of the AL population from the surrounding marine ecosystem. This study provides further compelling evidence that certain Cryptophyceae engage in a life‐history strategy, which includes alternating morphologically distinct cell‐types (dimorphism); cell‐types which without molecular analyses could be mistaken as novel taxa.


Publication title

Journal of Phycology










Institute for Marine and Antarctic Studies


Blackwell Publishing Inc

Place of publication

350 Main St, Malden, USA, Ma, 02148

Rights statement

© 2020 Phycological Society of America

Repository Status

  • Restricted

Socio-economic Objectives

Biodiversity in Antarctic and Southern Ocean environments

Usage metrics

    University Of Tasmania