Characterizing a new species of Nematoda using genetic and morphological analyses

Abstract

Nematodes (Nematoda) are slim tubular worms ranging between 0.5 mm – 2 mm in length and 10 to 100 µm thick. They have effectively adapted to inhabit all regions of the Earth, but are most commonly found in soils, decomposing vegetation, and freshwater sources. Ceanorhabditis elegans (C. elegans), an important member of this phylum, is a valuable model system. Owing to its small, fully sequenced genome, it is typically used to model the development of some diseases, such as neurodegenerative diseases. Nematodes are highly diverse, with over 30,000 species having not yet been described. While C. elegans will continue to be the primary model species, the classification of previously unknown species is valuable as it allows for study of the evolutionary pathway leading to each species, behavior and instincts, and how such animals behave as parasites. This diversity is exciting, and Drs. Kimberly Dej and Bhagwati Gupta work with students to document new species. In the laboratory, we use morphological analysis of the mouth, the pharynx, and the tail, combined with data generated by sequencing the 18S small ribosomal subunit rRNA gene to explore and document these new species. Here, we discuss how it was determined that a unique specimen collected from the Hamilton, Ontario area was found to have features of multiple genera: Oscheius and Ceanoreabditis.