Phytoliths are opal silica particles formed within plant tis- sues. Diatoms are aquatic, single-celled photosynthetic algae with silica skeletons. Phytolith and diatom morphotypes vary depending on local environmental and climatic conditions and because their silicate structures preserve well, the study of phytolith and diatom morphotypes can be used to better understand paleoclimatic and paleoenvironmental dynam- ics and changes. This article presents original data from an 820cm-deep stratigraphy excavated at the Hazen diatomite deposits, a high-elevation desert paleolake in the Fernley Dis- trict, Northern Nevada, USA. The site has been studied for an assemblage of fossilized threespine stickleback, Gasterosteus doryssus , that reveal adaptive evolution. For this study, a to- tal of 157 samples were extracted at 20 cm intervals cover- ing approximately 24,500 years. After extraction, the samples were mounted on slides and viewed under 40 0-10 0 0x light microscopy, enabling classification of 14 phytolith and 45 di- atom morphotypes. Our data support paleoenvironmental re- constructions of the Hazen Miocene paleolake. ∗
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International Code for Phytolith Nomenclature (ICPN) 2.0
Opal phytoliths (microscopic silica bodies produced in and between the cells of many plants) are a very resilient, often preserved type of plant microfossil. With the exponentially growing number of phytolith studies, standardization of phytolith morphotype names and description is essential. As a first effort in standardization, the International Code for Phytolith Nomenclature 1.0 was published by the ICPN Working Group in Annals of Botany in 2005. A decade of use of the code has prompted the need to revise, update, expand and improve it.
ICPN 2.0 formulates the principles recommended for naming and describing phytolith morphotypes. According to these principles, it presents the revised names, diagnosis, images and drawings of the morphotypes that were included in ICPN 1.0, plus three others. These 19 morphotypes are those most commonly encountered in phytolith assemblages from modern and fossil soils, sediments and archaeological deposits. An illustrated glossary of common terms for description is also provided.
- PAR ID:
- 10115770
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Annals of Botany
- ISSN:
- 0305-7364
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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