Gill Morphology in Two Bottom Feeder Mediterranean Sea Fishes: Grey Gurnard Fish (Eutrigla gurnardus, Linnaeus, 1758) and Striped Red Mullet Fish (Mullus barbatus surmuletus, Linnaeus, 1758) by Scanning Electron Microscopy

Abstract

Morfología de las Branquias en Dos SUMMARY:The purpose of the current investigation was to describe the gill morphology of two bottom feeders Mediterranean Sea fishes: Striped red mullet fish (M. surmuletus) and grey gurnard fish (E. gurnardus) that showed the same feeding habits. The gill system of the grey gurnard consisted of four pairs of gill arches while consisted of three pairs of gill arches in the striped red mullet. Our study focused on the scanning electron microscopical (SEM) features of the gills, where some differences in the gill arches and gill rakers surface in both species were observed. Our results marked that there was an interbranchial septum carrying a four transverse elevated crest in grey gurnard while in striped red mullet carrying a median longitudinal elevated crest. There are some similar structure on the gill arch of two fishes as; no angle between a ceratobranchial part and epibranchial part and also the gill arch has a region of many longitudinal microridges demarcated the region between gill rakers and gill filaments. By SEM, in striped red mullet, the smooth surface of gill arch and gill rakers was characterized by the presence of high number of taste buds. By SEM in grey gurnard, gill raker appeared as a round short projected body with high number of curved apex spines. Furthermore, in striped red mullet, gill raker appeared as short projected body with high number of rod-like spines. Gill filaments were long at middle and short at extremities of gill arch in both species.

Morphological studies on the gills of the European hake (Merluccius merluccius, Linnaeus, 1758)

“…The present study reveals that the gill cavity of M. merluccius was bounded by the mandible ventrally, by the roof of the oral and pharyngeal cavities dorsally, by the operculum laterally, and continued with each other medially. These results coincide with that obtained by Abumandour and El‐Bakary (); Alsafy (). While in puffer fish, Abumandour and Gewaily () reported that the gill cavity bounded by a three layered gill covering laterally; outer cutaneous layer, middle bony layer, and inner muscular layer.…”

“…The current work shows that the rostral ends of the gill arches were united to form inter branchial septum between the contra‐lateral gills. These findings like that obtained by Abumandour and El‐Bakary (), Abumandour and Gewaily (), Alsafy (), and Zayed and Mohamed ().…”

“…While Hossler et al () recorded that the gill arches lack this angle or have an acute angle in its middle part in filter feeding mullets Mugil cephalus . Moreover, Abumandour and El‐Bakary () reported the absence of this angle in Eutrigla gurnardus and M. barbatus surmuletus.…”

“…M. merluccius has four pairs of gills like most of teleost fishes (Abumandour & El‐Bakary, ; Alsafy, ; Díaz et al, ; Elsheikh, ; Kumari et al, ; Zayed & Mohamed, ). While Abumandour and Gewaily () in puffer fish and Abumandour and El‐Bakary () in Mullus barbatus surmuletus found three pairs of gills.…”

“…Many articles were recorded on the morphology of the gills in different fish species (Abumandour, , ; Abumandour & El‐Bakary, ; Abumandour & Gewaily, ; Alsafy, ; Díaz, Castro, García, de Astarloa, & Figueroa, ; Eiras‐Stofella, ; Eiras‐Stofella & Charvet‐Almeida, , ; Eiras‐Stofella & Fank‐de‐Carvalho, ; Lewis & Potter, ; Zayed & Mohamed, ), but the morphological characters of M. merluccius gills is out of focus so we will focus on it.…”