Presenter: Kristina Theam (University of Hawaii at Manoa)

Description:
Copepods are one of the most abundant multicellular animal groups on the planet. These microscopic crustaceans form the basis of most aquatic food webs, serving as the essential link between photosynthetic phytoplankton and larger, heterotrophic marine sea creatures. Sapphirinidae is a unique family of cyclopoid copepods found locally in Hawaiʻi. Copepods in this group are well known for their intensely iridescent cuticle, which gives their bodies a sapphire-like appearance. Interestingly, only male sapphirinids exhibit iridescence—females, on the other hand, are usually transparent. The sexual dimorphism exhibited in Sapphirinidae is believed to be linked to mate recognition, and a current hypothesis suggests that iridescent male bodies help females spot conspecifics in the open ocean. Despite these copepods’ unique morphology and their importance to local ecosystems, comprehensive studies assessing sapphirinid diversity in Hawaiian waters have not been conducted. This research project had two primary goals: (1) assess and quantify the extent of Sapphirinidae copepod diversity in Honolulu Harbor using DNA barcoding techniques, and (2) create a taxonomic resource for identification of sapphirinid copepods found in Hawaiʻi. To achieve these objectives, monthly plankton tows will be conducted from August 2021 to January 2022. Copepods from the family Sapphirinidae were sorted, counted, and photographed under a microscope. DNA barcoding results will be correlated with microscope photos to create a photographic resource for identifying sapphirinid copepods in future studies, and preliminary research has identified at least three distinct species groups in the harbor. This project will establish a “Rosetta Stone'' for Hawaiian sapphirinid identification by synthesizing historic taxonomic keys, modern microscope images, and DNA barcodes, opening up the door for more extensive studies on this unique family of copepods.