Abstract

A new species belonging to the toxin producing diatom genus Pseudo-nitzschia, P. hallegraeffii sp. nov., is delineated and described from the East Australian Current (EAC). Clonal cultures were established by single cell isolation from phytoplankton net hauls collected as part of a research expedition in the EAC region in 2016 on the RV Investigator. Cultures were assessed for their morphological and genetic characteristics, their sexual compatibility with other Pseudo-nitzschia species, and their ability to produce domoic acid. Light and transmission electron microscopy revealed cells which differed from their closest relatives by their cell width, rows of poroids, girdle band structure and density of band straie. Phylogenetic analyses based on sequencing of nuclear-encoded ribosomal deoxyribonucleic acid (rDNA) regions showed this novel genotype clustered within the P. delicatissima complex, but formed a discrete clade from its closest relatives P. dolorosa, P. simulans, P. micropora and P. delicatissima. Complementary base changes (CBCs) were observed in the secondary structure of the 3’ nuclear ribosomal transcribed spacer sequence region (ITS2) between P. hallegraeffii sp. nov. and its closest related taxa, P. simulans and P. dolorosa. Under laboratory conditions, and in the absence of any zooplankton cues, strains of P. hallegraeffii sp. nov. did not produce domoic acid (DA) and were not sexually compatible with any other Pseudo-nitzschia clones tested. A total of 18 Pseudo-nitzschia species, including three confirmed toxigenic species (P. cuspidata, P. multistriata and P. australis) have now been unequivocally confirmed from eastern Australia.

Highlights

  • Pseudo-nitzschia Peragallo is a pennate diatom genus with global marine distribution [1]

  • The abundance of these taxa was considered semi-quantitative because of known biases associated with net sampling (Sournia, 1978)

  • domoic acid (DA) was reported as ng mL-1 with the limit of detection for the analyses reported as 0.1 ng mL-1

Read more

Summary

Introduction

Pseudo-nitzschia Peragallo is a pennate diatom genus with global marine distribution [1]. KC147535, KC147516, AF417647, AY257840, JN050296, JN050288, AY081136, AY257850, AY081137, DQ336158, MF044022, MF044023, MF044024, MF044025, JN050299, JN085962, AF417639, DQ329204, KF482045, KF482053, KR021339, KR021310, KR021343, KR021311, JN050300, JN091756, KC147538, KC147523, DQ813814, DQ813839, JN252433, JN252422, AF440772, AY257844, AF417654, AY257843, KR021344, KR021314, AY257851, AF417640, AY257854, HQ111384, HQ111413, KM400615, KM400610, AY452526, AY452524, MF374777, MF374772, MF374778, MF374773, KR021349, KR021301, AF417644, AF417642, AY257860, EF531709, AY257839, KC759159, AF417675, FJ214162

Methods
Results
Conclusion
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.