Postembryonic ontogeny and functional anatomy of the ligamentum mandibulo-hyoideum and the ligamentum interoperculo-mandibulare, with notes on the opercular bones and some other cranial elements inSalmo gairdneri Richardson, 1836 (Teleostei: Salmonidae)

Abstract

This study deals with the development of the opercular bones the ligamentum mandibulo-hyoideum, the ligamentum interoperculo-mandibulare and with some aspects of the development of the ceratohyale and the cartilago meckeli during postembryonic ontogeny of Salmo gairdneri (rainbow trout). It is stated that the ligamentum mandibulo-hyoideum is present from hatching onward, while the development of the ligamentum interoperculo-mandibulare appears during the period of active feeding. Some functional reasons are proposed to explain these facts. It is further suggested that the opercular bones develop under influence of the opercular muscles.