# Phymatolithon calcareum

> species of alga (fossil)

**Wikidata**: [Q3381976](https://www.wikidata.org/wiki/Q3381976)  
**Source**: https://4ort.xyz/entity/phymatolithon-calcareum


## References

1. Taxonomy database of the U.S. National Center for Biotechnology Information
2. Integrated Taxonomic Information System
3. Encyclopedia of Life
4. Fossilworks
5. Global Biodiversity Information Facility
6. World Register of Marine Species
7. AlgaeBase
8. Dyntaxa
9. UMLS 2023
10. TAXREF v9.0
11. TAXREF v10.0
12. TAXREF v11.0
13. TAXREF v12.0
14. TAXREF v13.0
15. TAXREF v14.0
16. National Biodiversity Network
17. Nederlands Soortenregister
18. Barcode of Life Data Systems
19. Interim Register of Marine and Nonmarine Genera
20. SeaLifeBase
21. European Nature Information System
22. Ocean Biodiversity Information System
23. Belgian Species List
24. Open Tree of Life reference taxonomy version 3.2
25. Brazilian Flora 2020 project - Projeto Flora do Brasil 2020
26. Naturbasen