This study represents the first attempt to describe the ultra‐structural and histological features of different three age‐stages (young, mature, and adult) of rock pigeon Columba livia dakhlae captured from Egypt. The elongated tongue with round lingual apex carried a lingual nail rostrally on lingual tip. The current work gave a first record of numerous descriptions as in young and mature, small lingual nail formed from aggregation of lingual scales, but in adult, the nail formed from lingual membrane without any lingual scales. The current work gave full descriptive methods of shape, directions, and distribution of filiform‐like papillae with lingual scales among three age‐stages on dorsal surface and lateral border of apex and body. The taste buds present only on the tongue of mature and adult pigeon. The only one transverse row in young took the wide V‐shape but, wide U‐shape in mature and adult. The papillae on the papillary crest took triangular spoonful‐like shape in young and mature, but in adult take the shape of blunt tubercles. The current work was the first record of the presence of the openings of lingual glands on concave dorsal lingual surface of giant papillae and papillae of papillary crest in adult stage. The lingual membrane was thin one membrane in young and three to four layers in mature but, in adult it is well‐developed and formed from 10–11 layers. The supportive entoglossum cartilaginous was extended rostrally till the apical part.

The current investigation represented the first anatomical description of the buccal cavity of the grey gurnard Eutrigla gurnardus. For the achievement of this study, 10 heads of mature fish were used for SEM examinations. The morphological characteristic appearance of the buccal cavity has shown several adaptations in relation concerning its feeding habits. The median fissure of the upper lip divided the upper lip into two halves, this fissure appeared to be formed from many micro‐tubercles with numerous taste buds which aid in holding mucus secretion to the cell surface, help in mucus spread, and provide mechanical protection to the epithelium. Velum had two regions: median and peripheral region. The epithelium covering of the median region of the upper velum had dots‐like epithelial protrusion that carrying numerous taste buds, meanwhile, the epithelium covering of the lower velum not carried taste buds but instead carried numerous small scales‐like structures. The palate is divided into two semicircular regions by small region of microridges into the anterior and posterior region. The slightly bifid tongue had a median tubercle with numerous small taste buds on its dorsal surface. Concluded, these data were necessary to understand the adaptation of fish to its habitat and in developing a new and better method for fishing of this type of fish.

The current study shows the first attempts to clarify the gross, ultrastructure, and histological properties of the pecten oculi of the diurnal, visually active glossy ibis, as well as scanning electron microscope-energy dispersive X-ray (SEM-EDX) image analysis (Plegadis falcinellus). The pecten oculi was found on the eyeball's posteroin-

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The current investigation described the ultrastructural and histological features of the lingual papillary system in 14 adult Rhinopoma hardwickii using scanning electron and light microscopy, and immunohistochemical staining of keratin. Three types of lingual papillae were recognized; one filiform mechanical and two gustatory (fungiform and circumvallate) of three directions: posterior, posteromedian, and median.