Fundal variations in the eyes of the osteoglossomorph fishes

• Published in: Brain, behavior and evolution Vol. 27; no. 2-4; p. 80
• Main Authors: Saidel, W M, Braford, Jr, M R
• Format: Journal Article
• Language: English
• Published: Switzerland 01.01.1985
• Subjects: Adaptation, Biological; Animals; Choroid - anatomy & histology; Choroid - embryology; Choroid - physiology; Fishes - anatomy & histology; Retina - anatomy & histology; Retina - embryology; Retina - physiology; Species Specificity
• ISSN: 0006-8977
• DOI: 10.1159/000118722

The appearance of the fundus of the eye varies among the families of osteoglossomorph teleosts. In this study, four different fundal patterns were observed: (i) an anteroposterior (or horizontal) embryonic fissure with a septal falciform process (family Osteoglossidae); (ii) an embryonic fissure from the optic disc nasoventrally with a falciform process (family Arapaimidae); (iii) an embryonic fissure nasoventrally from the optic disc without a falciform process (family Hiodontidae); and (iv) neither an embryonic fissure nor a falciform process (families Notopteridae and Mormyridae). The distribution of these various forms among the osteoglossomorph fishes is consistent with the recent cladogram for the Osteoglossomorpha [Lauder and Liem, 1983] which was based on many characters. The embryonic fissure in adult Amia calva was also examined. Its existence in adult Amia, in most Osteoglossomorpha, and in many non-euteleostean bony fishes suggests that its persistence in the adult stage is a primitive trait of bony fishes, and its absence in the Notopteroidei (with the exception of Hiodon) is a derived condition.