Vol. 51 No. 8, 2012

Morphological Variations in the Scleral Ossicles of 172 Families of Actinopterygian Fishes with Notes on their Phylogenetic Implications

Hin-kui Mok¹ and Shu-Hui Liu^2,*

¹Institute of Marine Biology and Asia-Pacific Ocean Research Center, National Sun Yat-sen University, Kaohsiung 804, Taiwan
²Institute of Oceanography, National Taiwan University, 1 Roosevelt Road, Sec. 4, Taipei 106, Taiwan

Hin-kui Mok and Shu-Hui Liu (2012) This study reports on (1) variations in the number and position of scleral ossicles in 283 actinopterygian species representing 172 families, (2) the distribution of the morphological variants of these bony elements, (3) the phylogenetic significance of these variations, and (4) a phylogenetic hypothesis relevant to the position of the Callionymoidei, Dactylopteridae, and Syngnathoidei based on these osteological variations. The results suggest that the Callionymoidei (not including the Gobiesocidae), Dactylopteridae, and Syngnathoidei are closely related. This conclusion was based on the apomorphic character state of having only the anterior scleral ossicle. Having only the anterior scleral ossicle should have evolved independently in the Syngnathioidei + Dactylopteridae + Callionymoidei, Gobioidei + Apogonidae, and Pleuronectiformes among the actinopterygians studied in this paper.

Key words: Scleral ossicle, Actinopterygii, Phylogeny.

*Correspondence: Tel: 886-2-23636040 ext. 111. E-mail:shliu7867010@alumni.nchu.edu.tw