RESUMO
Goatfishes (Teleostei, Mullidae) are a group of mainly coastal fishes that form an important part of food chains, and also have commercial value. In the marine waters of Iran, they are found in the Persian Gulf and Oman Sea (Gulf of Oman). This study evaluated whether otolith morphology can be used to distinguish of species and genera, and also to interpret whether otoliths of the same species differ among two studied marine systems. To do this objective, the otolith morphology of ten species belonging to three genera were analyzed by SEM photography and shape analysis. Among the morphometric variables, relative rostrum length was found to be the most important otolith variable for discriminating Mulloidichthys (RRL = 32.29 ± 0.59) and Parupeneus (RRL = 37.39 ± 1.10), while rectangularity (REx) was the most important shape index for discriminating Mulloidichthys (REx = 0.99 ± 1.94) from Parupeneus (REx = 0.77 ± 1.21). By considering otolith morphology, Upeneus showed a better separation than the two other genera. The otoliths of Upeneus are diagnosed by short dorsal length (RDL = 69.35 ± 1.51), higher rostrum height (RRH = 53.63 ± 1.99), short rostrum (RRL = 31.12 ± 1.99), and antirostrum lengths (RanL = 12.38 ± 1.51). The most diverged phenotype within the genus Parupeneus was found for the otoliths of P. rubescens, and the most diverged phenotype within the genus Upeneus was found for the otoliths of U. sundaicus. The otoliths of the same species did not demonstrate large variation between the Persian Gulf and the Gulf of Oman. This study provides additional morphological evidence for the separation of goatfishes at the species and genus levels. We also underline that the slight observed differences between the otoliths of two marine systems are mainly caused by the ecological differences known between these two main systems.
RESUMO
The scale morphology of nine Mullidae taxa consisting of three genera and nine species from the Persian Gulf and the Gulf of Oman was described and compared using light and scanning electron microscopy from four different body regions. The general scale type in the studied mullid species was ctenoid except in the head region of Mulloidichthys vanicolensis and Parupeneus margaritatus, which had cycloid scales. The scales demonstrated a large focus with the central or centro-posterior position. The large variations of scale morphology were observed for the scales from different body regions of a single species. The shape of focus was in five types with the round type being the most common. In the scales of most examined species, there were 5-6 radii present in the anterior field. No radii exist in the lateral and posterior fields, and the radii orientation was parallel in all the studied species. The rostral margin of scales represented five types among the studied species; waved (M. vanicolensis), smooth in (P. rubescens), dentate (Upeneus doriae), scalloped (U. vittatus), and fluted (U. tragula). The lepidont shape varied among the species from blunt to flat, pointed, tiny, sharp, pointed, triangle, short, and long. The results also showed that the relative scale size has a desirable contribution to separate the examined genera. The scale morphological-based tree was largely consistent with the known systematics of the studied fishes. It was concluded that variation of scale characters has probably taxonomic and even phylogenetic information in both species and genus levels in the studied mullid fishes. However, variation of scale morphology between body regions, as shown in this study, suggests that scale characters should be used cautiously for taxonomic studies of these fishes.
Assuntos
Elétrons , Perciformes , Animais , Peixes , Microscopia Eletrônica de Varredura , FilogeniaRESUMO
Galathea ternatensis De Man, 1902 and Raymunida iranica n. sp., are reported from the Iranian coast as the first records of squat lobster species from the Persian Gulf. The new species morphologically resembles R. cagnetei Macpherson & Machordom, 2000, but is unique in the genus in having a small spine near the base of each supraocular spine and a spine ventral to the second branchial marginal spine of the carapace.
