The gut microbiome of many termites consists of a diverse range of protists that aid in the digestion of food particles. One of these families of protists is Oxymonadida. This project focuses on finding the evolutionary relationship between oxymonads and their most recent common ancestor, Trimastigidae, by building phylogenetic trees. This project was important because there is a large amount of species of oxymonads. This is because oxymonads adapt to the particular termite it lives in, and there are many species of termites. Understanding each species relationship helps give more knowledge and insight as to where some of the unknown species may go, even though they may not have DNA sequences yet. One unpublished sequence for Microrhopalodina was used in this paper, which previously had no molecular data available. The trees retrieved in this project had some discrepancies compared to previous studies and found an interesting relationship for Microrhopalodina. Microrhopalodina was included in the Oxymonas clade, indicating a very close relationship between the two species. It may even suggest that Microrhopalodina should be considered part of the species Oxymonas. Furthermore, Streblomastix branched in between Monocercomonoides and Trimastigidae, which is a different result than previous papers have found. Streblomastix was previously found to branch between Blattamonas and Monocercomonoides. The most recent paper on Blattamonas stated that they were unsure what family this species belongs to due to its molecular diversity, but its appearance resembles Monocercomonoides which is part of the family Polymastigidae. The trees produced in this project may indicate that Blattamonas belongs in the Polymastigidae family after all.

The termite Coptotermes gestroi is a small subterranean termite originating from Southeast Asia. The hindgut of C. gestroi contains five distinct species of parabasalid: Pseudotrichonympha leei, two undescribed species from the genus Holomastigotoides, and two undescribed species from the genus Cononympha. This study investigates the protist symbionts in C. gestroi and the relationship between their relative abundance as inferred by Illumina sequence reads and the directly observed abundances for each protist genus. Illumina amplicon sequencing as a means of DNA analysis is a proven method for identification and diversity analysis, although the specific ratios of sequence reads to cell abundance in protists is not well known. In this study, protist communities were observed under light microscopy; cells were counted under hemocytometer and characterized at the molecular level using Illumina amplicon sequencing. When comparing sequence read abundances to cell abundances, some general trends were found in both analysis methods. Cononmypha repeatedly formed the majority of the community, while Holomastigotoides and Pseudotrichonympha were responsible for a smaller yet similar portion of the population. Cell counts and sequence reads were also compared using an assumed linear model, with R2 values generated to quantify the relationship between both. The results suggest that Illumina sequencing can be used to obtain rough estimates of community diversity, but the high variability within the data suggest that the read abundances should be treated with caution.

The termite Zootermopsis nevadensis nuttingi, which is located in coastal forests of the western United States, plays an important ecological role in the breakdown and digestion of wood. Vital to this role are symbiotic protists residing in the termite's hindgut. Five protist genera of varying size and morphology make up this gut community. Despite years of study on this termite species, little was known about the spatial organization of the protist community within Zootermopsis nevadensis nuttingi. To resolve this issue, a study was conducted in which the distribution of protist genera among gut segments was observed and elucidated. This was done by separating hindgut segments, then counting the protists using a hemocytometer at a magnification of 200x. 60 segments from 20 termites were examined, and the total number of protists counted was 69,560. Images were also taken using a scanning electron microscope. Statistically significant, distinct distribution patterns were found for Trichonympha, Trichomitopsis and Streblomastix, while the small genera of Hexamastix and Tricercomitus appeared to have no special distribution. Trichomitopsis was more abundant in the posterior hindgut, Streblomastix was more abundant anteriorly, while the distribution of Trichonympha varied by colony. Hexamastix and Tricercomitus make up a large majority of the protists observed in any segment, followed by Streblomastix, Trichomitopsis and Trichonympha. Understanding the distribution of different protists within the hindgut may improve our understanding of the ecological relationships among protists as well as their individual roles in lignocellulose digestion, contributing to a better understanding of the hindgut system as a whole.