First record of the slender ponyfish, Equulites elongatus (Gunther, 1874) (Family: Leiognathidae) from the coasts of Muscat City at the Sea of Oman, Sultanate of Oman

摘要

Members of the family Leiognathidae are small-bodied and laterally compressed silvery sh (<300 mm SL) (Kimura et al., 2005). Shen and Lin (1985) reviewed Leiognathidae and recorded three genera and 12 species; since then the taxonomy of ponyshes has changed drastically, including the discovery of novel taxa. At present, this family comprises about 47 species belonging to nine genera (Chakrabarty et al., 2010). Equulites Fowler, 1904 is one of the recently resurrected genera within the family Leiognathidae to solve its taxonomic dilemma (Chakrabarty and Sparks, 2008; Kimura et al., 2008). This genus was originally described by Fowler (1904) as a subgenus of Leiognathus to encompass his newly described species Leiognathus vermiculatus Fowler, 1904 and Leiognathus virgatus Fowler, 1904 and more recently elevated to the generic level by Kimura et al. (2008). Members of this genus are widely spread within the entire geographic range of the family. They are sexually dimorphic with respect to light-organ volume and shape (Chakrabarty and Sparks, 2008). The genus Equulites comprises nine species: Equulites absconditus Chakrabarty & Sparks, 2010 from Northwest Pacic, Taiwan (Chakrabarty et al., 2010); Equuilites antongil (Sparks et al., 2005) from Western Indian Ocean, Madagascar (Eschmeyer, 2007); Equuilites elongatus (Gu¨nther, 1874) from Indo-West Pacic, east coast of Africa and o southwest India, eastwards to the Philippines, north to Japan, south to Australia (Froese and Pauly, 2010); Equuilites klunzingeri (Steindachner, 1898) from the Red Sea and Mediterranean Sea from Tunisia eastwards.