Discriminant Separation of Fishes: A Preliminary Study of Fish Eggs by Curie-Point Pyrolysis–Mass Spectrometry–Chemometric Analysis

Abstract

We conducted preliminary research to assess a new, nonlethal method for identifying larval fishes below currently recognized species levels. We used Curie-point pyrolysis and mass spectrometry to discriminate among fish egg samples representing Colorado squawfish Ptychocheilus lucius, Pahranagat roundtail chub Gila robusta jordani, and, two populations of cutthroat trout Oncorhynchus clarki. When preliminary data were processed by unsupervised pattern recognition (multivariate cluster and display methods), the species could be clearly discriminated. Variation within cutthroat trout samples was greater than variation in the other species. Results show that Curie-point pyrolysis with mass spectrometry provides characteristic chemotaxonomic information for the samples.