Otolith‐based species identification in the killifish Aphaniops (Teleostei; Cyprinodontiformes; Aphaniidae) using both morphometry and wavelet analysis
Eleni A. Charmpila, Azad Teimori, Bettina Reichenbacher
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引用次数: 0
Abstract
The killifish genus Aphaniops consists of nine species distributed in Eastern Africa and the Middle East. However, distinguishing these species from each other based on morphological traits is challenging. Here we investigate the utility of otoliths (sagittae) in distinguishing between A. dispar, A. ginaonis, A. hormuzensis, A. kruppi and A. stoliczkanus. Our approach is based on otoliths from 89 specimens and involves (1) otolith morphometrics, following prior recommendations, (2) shape analysis of otolith contours based on discrete wavelet transformation—a novel method in killifish otolith research—and comparative statistical analyses. Both methods reveal significant interspecific variation in the otolith regions of the rostrum, antirostrum and excisura. While method (1) effectively discriminates most species, method (2) struggles to differentiate A. hormuzensis, A. stoliczkanus and A. kruppi. Additionally, both methods encounter challenges in correctly classifying A. hormuzensis due to the high otolith variability of this species in our sample. Possible factors accounting for their variability are environmental fluctuations at the sampled hot sulphuric spring (Khurgo) and potential introgressive hybridization. We conclude that otolith morphometry is a valuable tool for Aphaniops species identification. Furthermore, we found that the distinctiveness of species‐specific otolith traits increases with the divergence age of the species.
期刊介绍:
Published regularly since 1920, Acta Zoologica has retained its position as one of the world''s leading journals in the field of animal organization, development, structure and function. Each issue publishes original research of interest to zoologists and physiologists worldwide, in the field of animal structure (from the cellular to the organismic level) and development with emphasis on functional, comparative and phylogenetic aspects. Occasional review articles are also published, as well as book reviews.