Otolith crystals (in Carapidae): Growth and habit

Abstract

The biomineralization of otoliths results mainly from the release of soluble Ca 2+, which is in turn precipitated as CaCO 3 crystals. In some Carapidae, sagittae sections have been shown to reveal a three-dimensional asymmetry with a nucleus close to the sulcal side, an unusual position. This study seeks to understand otolith formation in Carapus boraborensis. The unusual shape of the otolith is partly explained by the distribution of the epithelium cells, and particularly the sensory epithelium. Experimental evidence shows for the first time that aragonite growth takes place along the c-axis. These aragonite needles present two different habits. On the sulcal side is found the acicular form resulting from rapid growth during a short period of time. On the anti-sulcal side, the prismatic form seen there is due to a slower growth speed over longer periods. The otolith surface was observed each hour during a period of 24 h in fishes reared in similar conditions. This allowed for the first time the direct observation on the otolith surface of the deposition of the two layers (L-zone and D-zone). In C. boraborensis, the organic-rich layer (D-zone) develops during the day, whereas the CaCO 3 layer (L-zone) seems to be deposited during the night.

On the Origin of Amorphous Cores in Biomimetic CaCO3 Spherulites: New Insights into Spherulitic Crystallization

“…Previous biomimetic studies have already stated that ACC phase formed prior to the appearance of calcite or vaterite spherulites in several cases, − however, no further information was provided about the relationship between the two phases. On the other hand, CaCO 3 spherulitic biominerals are produced in several natural mineralizing systems, including stony corals, avian eggshells, and fish otoliths. − Previous observations have led to the belief that polycrystalline bundles grow from predisposed nucleation centers that are rich in either crystalline phase and/or organic materials . However, both the components of nucleation centers, and the mechanisms of these spherulitic biominerals formation are not fully understood.…”

“…In the field of biomineralization, spherulitic crystals are often referred to as “spherulitic biominerals”, a unique type of radial growing polycrystalline minerals that arises from matrix-mediated processes of site-directed nucleation. − Examples include scleractinian (stony) corals, avian eggshells, and fish otoliths. − Here too, the formation of the spherulitic biominerals is not well understood and remains a topic of debate. For example, geologists and biologists disagree about the growth of coral fibers.…”

Fish size effect on sagittal otolith outer shape variability in round gobyNeogobius melanostomus(Pallas 1814)

“…Sagittal otoliths are used widely for taxonomic and biological studies in non-ostariophysan teleosts because of their large size, relative ease of access and their variation in shape and size in different groups of fishes (Tuset et al, 2003). Otoliths have been used frequently in recent years for species, population and stock identification F I G U R E 1 Map of the Pomeranian Bay (with sampling routes located between A and B) (Duarte-Neto et al, 2008;Hüssy et al, 2016;Turan, 2006), in paleoichthyology (Gierl et al, 2018;Reichenbacher et al, 2007;Reichenbacher & Reichard, 2014) and bioarchaeology (van Neer et al, 2004), to identify fossil fish assemblages for phylogenetic or climatological studies (Andrus et al, 2002;Woydack & Morales-Nin,-2001), in trophic ecology (Tuset et al, 1996), and in functional morphology (Parmentier et al, 2007). In general, researchers (e.g., Pierce et al, 2009;Smale et al, 1995;Tuset et al, 2012) acknowledge that otoliths (mainly sagittae) are among the most widely used structures for identifying fish prey.…”

Morphology and morphometric relationships of the sagitta of <i>Diapterus auratus</i> (Perciformes: Gerreidae) from Veracruz, Mexico

“…The labyrinth includes three semicircular canals and three compartments: saculus, utriculus and lagena; each sac contains one otolith, the lapillus, the sagitta and the asteriscus, respectively (Morales-Nin 2000, Berra & Aday 2004, Popper et al 2005. Otoliths are calcareous concretions in the form of aragonite (Jawad 2007, Parmentier et al 2007, their taxonomic utility was recognized by Cuvier and their value in paleontology was first acknowledged by Koken (1884) (Tuset et al 2008). In most teleost, the sagitta is the largest otolith and the lapillus is the smallest among the three (Paxton 2000).…”