Contributions of the BioMar-ACG Project to the exploration and cataloging of marine macroalgae in the North Pacific of Costa Rica
DOI:
https://doi.org/10.15517/29j0jp96Keywords:
Chlorophyta; marine flora; Phaeophyceae; Rhodophyta; taxonomy.Abstract
Introduction: Costa Rica hosts remarkable marine biodiversity, vital for conserving its marine and coastal ecosystems. However, marine macroalgae remains understudied, especially in the Área de Conservación Guanacaste (ACG). To address this, the BioMar-ACG Project began in 2015 as a collaboration between the government, academic institutions, and NGOs, aiming to document marine biodiversity using morphological and molecular tools, with local community involvement. The project has since expanded macroalgal collections, identified new species, corrected misidentifications, and revealed high regional endemism.
Objective: To update the marine macroalgae inventory of the ACG using 2009-2024 collections from the BioMar-ACG Project and CIMAR-UCR previous projects, through morphological and molecular identification.
Methods: Surveys were conducted at 35 coastal and island sites, from intertidal zones to 20 m depth, using snorkeling and SCUBA techniques. Sampling occurred during both upwelling and non-upwelling seasons to capture environmental variability. Macroalgae were manually collected, documented in situ, and preserved for morphological and molecular analyses. DNA was extracted using commercial kits, targeting six molecular markers (COX, ITS, psbA, rbcL, tufA, and UPA) for genetic identification. Final taxonomic identifications integrated molecular and morphological data.
Results: A total of 562 specimens were analyzed, representing 101 species distributed among Rhodophyta (59 spp.), Heterokontophyta (22 spp.), and Chlorophyta (20 spp.). Thirty-one species were newly recorded for Costa Rica, 22 for the Pacific of Central America, and nine genera were documented for the first time in the region. Molecular analyses revealed nine potential new species to science.
Conclusions: The BioMar-ACG Project substantially increased knowledge of the marine flora of Costa Rica’s northern Pacific, doubling the number of species previously reported for the ACG. The discovery of new genera and species, together with high genetic divergence within groups such as Ceramiales and Dictyotales, highlights the underestimated and cryptic nature of macroalgal diversity in the Eastern Tropical Pacific. These findings emphasize the need for continuous exploration, molecular re-evaluation of historical records, and inclusion of diverse habitats and depth gradients in future studies. The integration of morphological and molecular data, combined with community-based research, has proven an effective model for strengthening biodiversity documentation and marine conservation in Costa Rica.
Downloads
References
Alvarado, J. J., Azofeifa-Solano, J. C., Beita-Jiménez, A., Cortés, J., Mena, S., Salas-Moya, C., & Fernández-García, C. (2021). Reef environments of Murciélago Islands and Santa Elena Peninsula, Guanacaste Conservation Area, Costa Rican Pacific. Revista Scientia Insularum, 4(1), 45–61. https://doi.org/10.25145/j.SI.2021.04.03 DOI: https://doi.org/10.25145/j.SI.2021.04.03
Camacho, O., Fernández-García, C., Vieira, C., Gurgel, C. F. D., Norris, J. N., Freshwater, D. W., & Fredericq, S. (2019). The systematics of Lobophora (Dictyotales, Phaeophyceae) in the western Atlantic and eastern Pacific oceans: Eight new species. Journal of Phycology, 55(3), 611–624. https://doi.org/10.1111/jpy.12850 DOI: https://doi.org/10.1111/jpy.12850
Cortés, J. (2017). Marine biodiversity baseline for Área de Conservación Guanacaste, Costa Rica: Published records. ZooKeys, 652, 129–179. https://doi.org/10.3897/zookeys.652.10427 DOI: https://doi.org/10.3897/zookeys.652.10427
Famà, P., Wysor, B., Kooistra, W. H. C. F., & Zuccarello, G. C. (2002). Molecular phylogeny of the genus Caulerpa (Caulerpales, Chlorophyta) inferred from chloroplast tufA gene. Journal of Phycology, 38(5), 1040–1050. https://doi.org/10.1046/j.1529-8817.2002.02009.x DOI: https://doi.org/10.1046/j.1529-8817.2002.t01-1-01237.x
Fernández-García, C., Riosmena-Rodríguez, R., Wysor, B., Tejada, O. L., & Cortés, J. (2011). Checklist of the Pacific marine macroalgae of Central America. Botanica Marina, 54(1), 53–73. https://doi.org/10.1515/BOT.2011.001 DOI: https://doi.org/10.1515/bot.2011.001
Fernández-García, C., Salas-Moya, C., Mena, S., Azofeifa-Solano, J. C., & Alvarado, J. J. (2021). Diversidad de los hábitats submareales de la Península de Santa Elena e Islas Murciélago, Pacífico Norte, Costa Rica. Revista de Biología Tropical, 69(S2), S160–S179. https://doi.org/10.15517/rbt.v69iS2.48774 DOI: https://doi.org/10.15517/rbt.v69iSuppl.2.48774
Fernández-García, C., Wysor, B., Riosmena-Rodríguez, R., Peña-Salamanca, E., & Verbruggen, H. (2016). DNA-assisted identification of Caulerpa (Caulerpaceae, Chlorophyta) reduces species richness estimates for the Eastern Tropical Pacific. Phytotaxa, 252(3), 185–204. https://doi.org/10.11646/phytotaxa.252.3.2 DOI: https://doi.org/10.11646/phytotaxa.252.3.2
Freshwater, D. W., Idol, J. N., Parham, S. L., Fernández-García, C., León, N., Gabrielson, P. W., & Wysor, B. (2017). Molecular assisted identification reveals hidden red algae diversity from the Burica Peninsula, Pacific Panama. Diversity, 9(2), 19. https://doi.org/10.3390/d9020019 DOI: https://doi.org/10.3390/d9020019
Freshwater, D. W., & Rueness, J. (1994). Phylogenetic relationships of some European Gelidium (Gelidiales, Rhodophyta) species based on rbcL nucleotide sequence analysis. Phycologia, 33(3), 187–194. https://doi.org/10.2216/i0031-8884-33-3-187.1 DOI: https://doi.org/10.2216/i0031-8884-33-3-187.1
Goff, L. J., Moon, D. A., & Coleman, A. W. (1994). Molecular delineation of species and species relationships in the red algal agarophytes Gracilariopsis and Gracilaria (Gracilariales). Journal of Phycology, 30(3), 521–537. https://doi.org/10.1111/j.0022-3646.1994.00521.x DOI: https://doi.org/10.1111/j.0022-3646.1994.00521.x
Hall, T. A. (1999). BioEdit: A user-friendly biological sequence alignment editor and analysis program for Windows 95/98/NT. Nucleic Acids Symposium Series, 41, 95–98.
Kogame, K., & Masuda, M. (2001). Crustose sporophytes of Colpomenia bullosa (Scytosiphonaceae, Phaeophyceae) in nature. Cryptogamie Algologie, 22(2), 201–208. DOI: https://doi.org/10.1016/S0181-1568(01)01064-9
Kogame, K., Uwai, S., Shimada, S., & Masuda, M. (2005). A study of sexual and asexual populations of Scytosiphon lomentaria (Scytosiphonaceae, Phaeophyceae) in Hokkaido, northern Japan, using molecular markers. European Journal of Phycology, 40(3), 313–322. https://doi.org/10.1080/09670260500254929 DOI: https://doi.org/10.1080/09670260500193008
Kumar, S., Stecher, G., Suleski, M., Sanderford, M., Sharma, S., & Tamura, K. (2024). Molecular Evolutionary Genetics Analysis Version 12 for adaptive and green computing. Molecular Biology and Evolution, 41, 1–9. DOI: https://doi.org/10.1093/molbev/msae263
Saunders, G. W. (2005). Applying DNA barcoding to red macroalgae: A preliminary appraisal holds promise for future applications. Philosophical Transactions of the Royal Society B: Biological Sciences, 360(1462), 1879–1888. https://doi.org/10.1098/rstb.2005.1719 DOI: https://doi.org/10.1098/rstb.2005.1719
Sherwood, A. R., & Presting, G. G. (2007). Universal primers amplify a 23S rDNA plastid marker in eukaryotic algae and cyanobacteria. Journal of Phycology, 43(3), 605–608. https://doi.org/10.1111/j.1529-8817.2007.00341.x DOI: https://doi.org/10.1111/j.1529-8817.2007.00341.x
Silberfeld, T., Leigh, J. W., Verbruggen, H., Cruaud, C., de Reviers, B., & Rousseau, F. (2010). A multi-locus time-calibrated phylogeny of the brown algae (Heterokonta, Ochrophyta, Phaeophyceae): Investigating the evolutionary nature of the “brown algal crown radiation.” Molecular Phylogenetics and Evolution, 56, 659–674. https://doi.org/10.1016/j.ympev.2010.04.020 DOI: https://doi.org/10.1016/j.ympev.2010.04.020
Tronholm, A., Afonso-Carrillo, J., Sansón, M., Leliaert, F., Fernández-García, C., & De Clerck, O. (2013). Taxonomy of the Dictyota ciliolata–crenulata complex (Dictyotales, Phaeophyceae). Phycologia, 52, 171–181. https://doi.org/10.2216/12-005.1 DOI: https://doi.org/10.2216/12-005.1
Viales-Cubillo, M., Quesada-Pérez, F., Díaz-Canales, P., González-Sánchez, K., & Fernández-García, C. (2025). Integrative approach to species delimitation in Sargassum (Fucales, Phaeophyceae) from the Central American Pacific based on morphological and genetic evidence. Diversity, 17(9), 592. https://doi.org/10.3390/d17090592 DOI: https://doi.org/10.3390/d17090592
Wehrtmann, I. S., & Cortés, J. (Eds.). (2009). Marine biodiversity of Costa Rica, Central America. Springer Netherlands. DOI: https://doi.org/10.1007/978-1-4020-8278-8
Yoon, H. S., Hackett, J. D., & Bhattacharya, D. (2002). A single origin of the peridinin- and fucoxanthin-containing plastids in dinoflagellates through tertiary endosymbiosis. Proceedings of the National Academy of Sciences, 99(18), 11724–11729. https://doi.org/10.1073/pnas.172234799 DOI: https://doi.org/10.1073/pnas.172234799
Downloads
Additional Files
Published
Issue
Section
License
Copyright (c) 2026 Revista de Biología Tropical

This work is licensed under a Creative Commons Attribution 4.0 International License.
Creative Commons Attribution 4.0 License (CC BY 4.0)
Attribution (BY) • (BY) You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work).
