Hidden in plain sight: freshwater sponges in eastern Washington
Faculty Mentor
Camille McNeely
Presentation Type
Poster
Start Date
4-14-2026 9:00 AM
End Date
4-14-2026 11:00 AM
Location
PUB NCR
Primary Discipline of Presentation
Biology
Abstract
Freshwater sponges are immobile, filter-feeding invertebrates that can have photosynthetic algal symbionts in their tissues. However, they remain poorly documented relative to other freshwater organisms. So far, no published studies describe the populations of freshwater sponges in eastern Washington. The goal of this study is to document the distribution and diversity of freshwater Porifera in this region. We conducted an initial census of 27 stream sites in late summer 2021. At each site, we searched the reach for 1 hour and examined at least 100 substrate particles. We measured water quality parameters including temperature, dissolved oxygen, turbidity, pH, oxidative-reductive potential (ORP), and concentrations of nitrogen and phosphorus. We found freshwater sponges in 9 of the 27 sites. The only water quality parameter that was significantly associated with sponge presence was temperature. Sites had warmer water where sponges were present compared to sites without sponges (t-test, t = 3.43, P= 0.003). We used cytochrome oxidase subunit I gene (COI mtDNA) sequences and compound microscopy of gemmuloscleres and megascleres to identify sponges. We observed 4 common genera (Heteromeyenia, Ephydatia, Eunapius, Spongilla), but were unable identify all specimens. We will build on this work with additional sampling during spring and summer of 2026, followed by improved genetic and microscopic techniques. Additional species, with different environmental requirements, may be present earlier in the year. Where sponges are present, specimens will be collected for phenotypic and genetic analyses. Phenotypic traits will be analyzed through scanning electron microscopy (SEM) to examine diagnostic structures such as spicules and gemmuloscleres. Genetic traits will be assessed using optimized DNA extraction and amplification protocols targeting commonly used mitochondrial markers for freshwater sponge identification. We may also include genetic analysis of algal symbionts. This research aims to improve our knowledge and understanding of freshwater sponge populations in eastern Washington. By combining field sampling, SEM phenotypic classification, and genetic techniques, this research will contribute to a better understanding of these freshwater invertebrates and their symbiotic relationships.
Recommended Citation
Dickson, Kayla, "Hidden in plain sight: freshwater sponges in eastern Washington" (2026). 2026 Symposium. 25.
https://dc.ewu.edu/srcw_2026/ps_2026/p1_2026/25
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Hidden in plain sight: freshwater sponges in eastern Washington
PUB NCR
Freshwater sponges are immobile, filter-feeding invertebrates that can have photosynthetic algal symbionts in their tissues. However, they remain poorly documented relative to other freshwater organisms. So far, no published studies describe the populations of freshwater sponges in eastern Washington. The goal of this study is to document the distribution and diversity of freshwater Porifera in this region. We conducted an initial census of 27 stream sites in late summer 2021. At each site, we searched the reach for 1 hour and examined at least 100 substrate particles. We measured water quality parameters including temperature, dissolved oxygen, turbidity, pH, oxidative-reductive potential (ORP), and concentrations of nitrogen and phosphorus. We found freshwater sponges in 9 of the 27 sites. The only water quality parameter that was significantly associated with sponge presence was temperature. Sites had warmer water where sponges were present compared to sites without sponges (t-test, t = 3.43, P= 0.003). We used cytochrome oxidase subunit I gene (COI mtDNA) sequences and compound microscopy of gemmuloscleres and megascleres to identify sponges. We observed 4 common genera (Heteromeyenia, Ephydatia, Eunapius, Spongilla), but were unable identify all specimens. We will build on this work with additional sampling during spring and summer of 2026, followed by improved genetic and microscopic techniques. Additional species, with different environmental requirements, may be present earlier in the year. Where sponges are present, specimens will be collected for phenotypic and genetic analyses. Phenotypic traits will be analyzed through scanning electron microscopy (SEM) to examine diagnostic structures such as spicules and gemmuloscleres. Genetic traits will be assessed using optimized DNA extraction and amplification protocols targeting commonly used mitochondrial markers for freshwater sponge identification. We may also include genetic analysis of algal symbionts. This research aims to improve our knowledge and understanding of freshwater sponge populations in eastern Washington. By combining field sampling, SEM phenotypic classification, and genetic techniques, this research will contribute to a better understanding of these freshwater invertebrates and their symbiotic relationships.
