Histomicroscopy and normal anatomy of the adult killifish Aphanius hormuzensis (Teleostei; Aphaniidae) from the Persian Gulf coastal environment

Abstract

The histomicroscopy and normal anatomy of the major body organ systems were investigated in the adult killifish, Aphanius hormuzensis using histological examination, X‐ray imaging, double staining, light microscopy and scanning electron microscopy (SEM). Based on the histomicroscopic observations, the kidney, liver and swim bladder in the studied species were comparable to other fish models. The anterior portion of the kidney is bulbous, while the posterior portion is narrow and elongated; the liver has a single lobe and the swim bladder is a single‐chambered organ with no connection to the digestive tract (physoclistous). X‐ray imaging and double staining examination showed 12 abdominal and 15 caudal vertebrae and a single hypural plate in the caudal skeleton. According to light microscopy, the scales were rounded to pentagonal in shape with three types of radii (primary, secondary and tertiary), and the urohyal bone was elongated. SEM microscopy showed a single row of tricuspid teeth on the upper and lower jaw, respectively, each tooth has two lateral cusps that are shorter than the middle one. The number of teeth was 17–18 in the upper jaw and 19–20 in the lower jaw. The saccular otoliths were rounded‐trapezoid in shape with a moderately incised and V‐shaped excisura. The members of killifishes are an important group for biologists because of their evolutionary properties, regeneration capacity and usefulness as biological control and also for the ecotoxicological assessment of environmental pollution. The outcomes of this study may provide a useful basis for future research on the genus Aphanius.

New osteological and morphological data of four species ofAphaniops(Teleostei; Aphaniidae)

“…One outcome of our study was that the examined specimens of A. dispar , A. hormuzensis , A. kruppi, and A. stoliczkanus all exhibited a sinuous and thick epural bone in their caudal skeleton. This characteristic had previously been reported for A. stoliczkanus (as Aphanius dispar in Costa, 2012a), A. richardsoni, A. ginaonis, and A. hormuzensis (Costa, 2012a; Motamedi et al., 2018; Teimori et al., 2014). Conversely, a sinuous shape of the epural is absent in A. furcatus and it is also absent in the related Paraphanius mento (this study and Teimori et al., 2014).…”

“…Moreover, as none of the previous molecular studies had included both A. kruppi and A. hormuzensis , we aimed to generate a molecular tree that includes each of the species studied here. For the morphological study, we put a special focus on the osteology of the caudal skeleton, posterior vertebral column, and median fins, which has previously solely been studied in A. hormuzensis (see Motamedi, Shamsaldini, Teimori, & Askari Hesni, 2018). Furthermore, we examined whether some of the osteological characters suggested for taxonomic purposes for species of Pampus (Stromateidae, Perciformes; see Jawad & Jig, 2017) and for species of the Tripterygiidae (Blenniiformes; see Jawad, Fricke, & Näslund, 2018) could also be suitable for discrimination among the here studied species.…”

Ontogenetic pattern, morphological sexual and side dimorphism in the saccular otolith of a scaleless killifish Aphanius furcatus (Teleostei: Aphaniidae)

“…The killifish Aphanius Nardo, 1827, is naturally distributed in coastal and freshwater habitats along the Mediterranean Sea, the Red Sea and the Persian Gulf and also occurs in land‐locked environments such as ponds and spring‐stream systems in Turkey and Iran (Teimori, Esmaeili, Hamidan, & Reichenbacher, 27; Teimori, Mostafavi, & Esmaeili, 29; Wildekamp, 35). To date, various methods, including hybridization experiments, genetic analyses, multivariate analysis of morphometric and meristic counts, comparative analyses of osteology and coloration, and histopathological analysis, have been used to investigate different aspects of this taxon (Esmaeili, Teimori, Gholami, Zarei, & Reichenbacher, 3; Maltagliati et al, 8; Masoudi et al, 9; Motamedi, Iranmanesh, Teimori, Sadjjadi, & Nasibi, 14; Motamedi, Shamsaldini, Teimori, & Askari Hesni, 15; Teimori et al, 28; Tigano, Ferrito, & Nicosia, 30; Valdesalici, Langeneck, Barbieri, Castelli, & Maltagliati, 32; Zeinali & Motamedi, 36). In most of these studies, otolith has a desirable contribution to a better understanding of the species description, species diversification, distribution pattern, detection of hybrids and the historical biogeography.…”

Early embryonic development of brackish water Killifish Aphanius hormuzensis (Teleostei, Aphaniidae) inhabiting coastal environment in Southern Iran

“…It is a secondary freshwater fish and is well known for its remarkable capacity to adapt to different ecological conditions (Teimori et al., ). Thus, it is generally an attractive model to be studied for different aspects including the understanding of ecological plasticity, evolutionary processes, environmental studies, histopathological changes and recently regeneration capacity (Ferrito et al., ; Iranmanesh & Motamedi, ; Motamedi, Shamsaldini, Teimori, & Askari Hesni, ; Parenti, ; Saeed, Al‐Naema, Butler, & Febbo, ; Teimori et al., ; Tigano et al., ; Wildekamp, Kücük, Ünlüsayin, & Neer, ; Zeinali & Motamedi, ).…”