Comparative morphology of urohyal bone in brackish water species of the genus Aphanius Nardo, 1827 in the Persian Gulf and Southeastern Mediterranean Sea basins (Teleostei: Aphaniidae)

Abstract

Among the skeletal elements in fishes, the urohyal bone which lies in the lower part of the head - the central part of the mandibular skeleton- has proved to be of special significance in fish systematics. The urohyal bone is considered to be a synapomorphic structure in teleostean fish. The urohyal bone of six brackish water Aphanius species (i.e., Aphanius hormuzensis, A. stoliczkanus, A. furcatus, A. ginaonis, A. mento, A. sirhani) was compared using morphological description and linear measurements to explore the effectiveness of urohyal bone morphology in the separation of the Aphanius species. Description of the urohyal bones and their morphological variation allowed identification of the A. furcatus, A. mento and A. sirhani from their relatives. Moreover, the UH.UL separates significantly A. dispar and A. ginaonis, and the MH.UL discriminates significantly A. mento from others studied relatives. Discriminant function analysis (DFA) separated the studied species with high classification success (overall mean 94.7%). These results suggest the power of urohyal bone morphology in separating of the Aphanius species analyzed, and highlighting the taxonomic value of the urohyal bone. By considering the phylogenetic relationships among the studied species, it can be concluded that the observed variation in their urohyal morphology is largely consistent with their phylogeny. This indicated that at least some morphological characters in the shape of urohyal bone in Aphanius are encoded probably by genetic factors, which can be used for species discrimination.

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

“…Furthermore, our study revealed that the urohyal bone of A. hormuzensis is generally characterized by a moderately elongated and thickened basibranchial attachment (see Figure 15c). According to a comparative study by Teimori, Motamedi, and Iranmanesh (2018), it can be concluded that this characteristic morphology is typical for the brackish water species of Aphanius.…”

“…In addition, several authors have documented that morphological characteristics related to hard structures can provide important taxonomic and phylogenetic information in Aphanius species, the studied hard parts included scales (Gholami, Teimori, Esmaeili, Schulz-Mirbach, & Reichenbacher, 2013;Teimori, 2018;Teimori, Motamedi, & Manizadeh, 2017), the urohyal bone (Teimori, Motamedi, & Iranmanesh, 2018), jaw teeth (Teimori, Esmaeili, Erpenbeck, & Reichenbacher, 2014), and otoliths (e.g., Reichenbacher, Sienknecht, Küchenhoff, & Fenske, 2007;Reichenbacher, Kamrani, Esmaeili, & Teimori, 2009;Teimori et al, 2012;Teimori, Esmaeili, et al, 2018).…”

DNA barcoding and species delimitation of the Old World tooth-carps, family Aphaniidae Hoedeman, 1949 (Teleostei: Cyprinodontiformes)

“…fasciatus groups. Parenti [28], has been summarized several diagnostic features for Aphanius mento (now Paraphanius mento) that are not found in the members of Aphanius and Aphaniops, including a cartilaginous interhyal (ossified in Aphanius and Aphaniops), an embedded urohyal (not embedded in Aphanius and Aphaniops, see also Teimori et al [59]), an upturned lower jaw (not upturned in other Aphanius and Aphaniops), and a distinctive neuromast pattern on the dorsal surface of the head (less prominently developed in Aphanius and Aphaniops species). Therefore, she proposed A. mento as a derived member of the Aphanius-like clade that should be designated as "Aphanius".…”

“…Synonym of Lebias Goldfuss 1820, according to Lazara [30,26]. Valid as Aphanius Nardo 1827, according to Tortonese [31], Parenti [28], Wildekamp et al [32], Coad [33], Kruppand Schneider [34], Wildekamp [16], Poll & Gosse [35], Seegers [36], Wildekamp et al [23], Doadrio et al [37], Huber [38], Blanco et al [39], Hrbek et al [40], Kottelat et al [41], Kottelat & Freyhof [42], Hertwig [43], Coad [44], Teimori et al [45], Esmaeili et al [46], Teimori et al [47], Esmaeili et al [19], Gholami et al [48], Keivany & Esmaeili [49], Esmaeili et al [50], Teimori et al [51], Pfleiderer et al [52], Huber [53], Jouladeh-Roudbar et al [54], Esmaeili et al [55], Freyhof et al [9,10], Ç içek et al [56], Esmaeili et al [57], Golani & Fricke [58], Teimori et al [15,59], Yoğurtçuoğlu & Freyhof [60], Teimori & Motamedi [61], and Motamedi et al [62].…”

Shape variation and functional adaptation in a structure involved in the feeding system of gobiid fishes

“…The urohyal bone is not easily digested in the stomach of predators; therefore, it has been used in trophic studies of the aquatic-and aquatic related animals such as fish, seals and birds (Hansel et al, 1988;Pierce et al, 1991;Johdal et al, 2001;Tombari et al, 2010). Moreover, owing to its morphological variability, the urohyal bone has been used extensively in fish taxonomy for species identification and even the discrimination among the genera and families (e.g., Kusaka, 1974;Pierce et al, 1991;Esmaeili & Teimori, 2006;Jawad et al, 2017;Teimori et al, 2018).…”