Meeting Abstract
Sexual selection may lead to increased diversification of species, as exemplified by origins of luminous courtship in multiple animal groups, including cypridinid ostracods (Crustacea). Dozens of species of cypridinids radiated in the Caribbean using a wide range of luminous courtship displays. Although the biochemistry and genetics of bioluminescence are well studied, easily culturable luminous animals are rare, making many types of experiments intractable. Here we report progress toward keeping the luminous ostracod Vargula tsujii through full life-cycles in laboratory aquariums. The California Sea Firefly (Vargula tsujii) is found within the clade of ostracods that uses bioluminescence for courtship, but represents a loss of this ability, using bioluminescence purely for defense. Vargula tsujii is geographically isolated from closely related species in the Caribbean, found in Southern California and more accessible to our lab. However, almost nothing is known about the life cycle and development of this species. To address this need, we measured hundreds of wild-collected animals. We present multi-dimensional k-means clustering analyses to quantify the size and shape of instar stages for V. tsujii development. Within custom aquariums, we show through measurement of lab-reared animals that we raised a full life cycle of V. tsujii in the laboratory, a first for any luminous ostracod. These results, combined with descriptions of development and molting times, provide insight into the life cycle of V. tsujii. This research will facilitate the understanding of bioluminescence and will allow a host of new laboratory experiments to study sexual dimorphism, sexual selection, and link genes to the diversification of species and courtship signals.
