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POLYMORPHISM IN THE DESMID XANTHIDIUM REGULARE AND ITS TAXONOMIC IMPLICATIONS
C E de Mattos Bicudo1, L M de Carvalho1
1Cryptogamic Section, Instituto de Botanica, Caixa Postal 4005, Sao Paulo, BrazilPhycology Laboratory, Department of Ecology, Instituto de Biociéncias Universidade Federal de Pernambuco, Caixa Postal 2976, Recife, Pernambuco, Brazil.
Journal of Phycology
|April 21, 2016
Summary
Polymorphism in the desmid genus Xanthidium Ehr. was studied in Brazil. Researchers propose consolidating several taxa under Xanthidium regulare Nordst., clarifying its taxonomic classification.
Area of Science:
- Phycology
- Algology
- Freshwater biology
Background:
- The desmid genus Xanthidium Ehr. exhibits significant morphological variation.
- Understanding polymorphism is crucial for accurate species identification and classification in algae.
Purpose of the Study:
- To investigate the polymorphism of Xanthidium Ehr. species from Lake Dais Irmaios, Brazil.
- To clarify the taxonomic status of Xanthidium regulare Nordst., Xanthidium fragile Borge, and Xanthidium pseudoregulare Borge.
Main Methods:
- Microscopic examination of approximately 1300 specimens collected over two years.
- Comparative morphological analysis of Xanthidium Ehr. taxa.
Main Results:
- Observed extensive morphological variation within Xanthidium regulare Nordst., Xanthidium fragile Borge, and Xanthidium pseudoregulare Borge.
- Identified several previously described taxa as synonymous with Xanthidium regulare Nordst. var. asteptum Nordst. in Borge.
- Reclassified Xanthidium pseudoregulare Borge as a variety of Xanthidium regulare Nordst.
Conclusions:
- Xanthidium regulare Nordst. is retained as a valid species pending further research.
- Established Xanthidium regulare Nordst. var. asteptum Nordst. in Borge emend. C. Bic. & L. M. Carv. as the correct name for a consolidated variety.
- Proposed Xanthidium regulare Nordst. var. pseudoregulare (Borge) C. Bic. & L. M. Carv. as a new combination.
- Provided an identification key for the three proposed varieties of Xanthidium regulare Nordst.
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