| This paper reviews the quantitative morphological variation published for Sagitta setosa Müller, 1847 and two other species described within the S. serosa-complex, viz., S. euxina Moltschanoff, 1909 from the Black Sea, and S. batava Biersteker & Van der Spoel, 1966 from the Scheldt Estuary (Netherlands). Data on total (body) length, caudal length, numbers of teeth and hooks, ovary length, and dimensions of fins are compared between these three taxa. Additionally, samples from the North Sea, Mediterranean, and Black Sea are compared to look for geographic differences. Specimens from the Mediterranean were smallest with relatively long caudal segments, and few teeth and hooks, whereas specimens from the Black Sea were largest with relatively short caudal... |
