Sciaenid Inner Ears: A Study in Diversity

Abstract

Sciaenid fishes (Family Sciaenidae) could potentially serve as models for understanding the relationship between structure and function in the teleost auditory system, as they show a broad range of variation in not only the structure of the ear but also in the relationship between the ear and swim bladder. In this study, scanning electron microscopy (SEM) was used to investigate inner ear ultrastructure of the Atlantic croaker (Micropogonias undulatus), spotted seatrout (Cynoscion nebulosus), kingfish (Menticirrhusamericanus) and spot (Leiostomus xanthurus). These species reflect the diversity of otolith and swim bladder morphology in sciaenids. The distribution of different hair cell bundle types, as well as hair cell orientation patterns on the saccular and lagenar maculae of these fishes were similar to one another. The rostral ends of the saccular sensory epithelia (maculae) were highly expanded in a dorsal-ventral direction in the Atlantic croaker and spotted seatrout as compared to the kingfish and spot. Also, ciliary bundles of the saccular maculae contained more stereocilia in the Atlantic croaker and spotted seatrout as compared with kingfish and spot. The shapes of the lagenar maculae were similar in all four species. In the Atlantic croaker and spotted seatrout lagenar maculae, the number of stereocilia per bundle was greater than those for the kingfish and spot. Given that saccular macula shape and numbers of stereocilia per bundle correlate with swim bladder proximity to the ear in the studied species, it is possible that inner ear ultrastructure could be indicative of auditory ability in fishes.

Diversity in Fish Auditory Systems: One of the Riddles of Sensory Biology

“…All maculae stem from species that possess accessory hearing structures (A-J). For the maculae in (H-J) no scale bars were given in the original publications (Ramcharitar et al, 2001(Ramcharitar et al, , 2004. Illustrations modified from Coombs and Popper (1982), Deng et al (2011), Ladich and, Platt (1977), Popper (1977Popper ( , 1981, Platt and Popper (1981a), Ramcharitar et al (2001Ramcharitar et al ( , 2004, and Platt et al (2004).…”

“…For the maculae in (H-J) no scale bars were given in the original publications (Ramcharitar et al, 2001(Ramcharitar et al, , 2004. Illustrations modified from Coombs and Popper (1982), Deng et al (2011), Ladich and, Platt (1977), Popper (1977Popper ( , 1981, Platt and Popper (1981a), Ramcharitar et al (2001Ramcharitar et al ( , 2004, and Platt et al (2004). a, anterior;d, dorsal. lagenae is almost as large as or even larger than the macula sacculi (except in Amia), which contrasts the condition in many teleost species (Platt and Popper, 1981a;Ladich and Popper, 2004).…”

Ontogenetic and interspecific variation in hearing ability in marine fish larvae

“…These 2 species have differences in their peripheral auditory structures, which were thought to be responsible for the difference in auditory abilityspecies from the subfamily Myripristinae have a direct connection between the swim bladder and the auditory bulla, whilst species from the genus Adioryx lack such connections (Coombs & Popper 1979). Similarly, among adults of sciaenid species, there are a range of auditory specialisations, and, consequently, different species have very different auditory capabilities (Ramcharitar et al 2001(Ramcharitar et al , 2006. One sciaenid species, Bairdiella chrysoura, can detect sounds of up to 4000 Hz, and this ability is suspected to be due to morphological specialisations of the inner ear and swim bladder (Ramcharitar et al 2004).…”

Testing otolith morphology for measuring marine fish biodiversity

“…These features were also implicit in the warps obtained, but the major problem is that these patterns can be partially biased from a morpho-functional perspective: croakers or drums (Sciaenidae, Perciformes) and flatfish (Pleuronectiformes) belong to Group 1, but the shape of the sulcus in flatfish is completely different from that in the croakers. From a functional perspective, croakers are considered specialists in sound production (Luczkovich et al 1999;Ramcharitar et al 2001), whereas flatfish are not hearing specialists (Popper and Fay 1993). For this reason, the inclusion of sulcus shape provided relevant functional information.…”