World Journal of Fish and Marine Sciences 2 (6): 499-504, 2010 ISSN 2078-4589 © IDOSI Publications, 2010 Corresponding Author: Amir Jaferian, Department of Marine Science, Marine Science and Technology of Khoramshahr University, Khoramshahr, Khuzestan, 61534345, Iran E.Mail: jaferian@yahoo.com 499 Morphometric Study of Eleutheronema tetradactylum in Persian Gulf Based on The truss Network Amir Jaferian, Hossain Zolgharnian, Mehdi Mohammadi, 1 1 2 Mohamad-Ali Salari-Aliabadi and Seyed-Javad Hossini 1 2 Department of Marine Science, 1 Marine Science and Technology of Khoramshahr University, Khoramshahr, 6153435, Iran Department of Biotechnology, Persian Gulf Research and Study Center, 2 Persian Gulf University, Bushehr, 5983241, Iran Abstract: Identifying intraspecific units or stocks of a species with unique morphological characters enables a better management of these subunits of species and ensures perpetuations of the resources.Fourfinger Threadfin (Eleutheronema tetradactylum-Shaw,1804) in is described from the Persian Gulf in Iran. Researchers have traditionally used multivariate analysis of several linear measures (‘trusses’) across the body form to quantify shape. The truss measurements were also used to assess the principal shape components of different sized Fourfinger Threadfin.Truss and length measurements were made on 79 Eleutheronema tetradactylum of known mass. Fourteen-one morphometric measurements were made for each individual, data collection is correct by allometric equation(Elliott -1995) for body size different and, using Discriminant Function Analysis(DFA). Univariate analysis (One-way ANOVA) of 13 characteristics among the samples showed significant differences in the Eleutheronema tetradactylum population in the two zones of sampling. Analysis(DFA) and Eginvalue 0.958 which showed non diversity in the Elenutheronema tetradactylum population in the two zones of sampling. Our result showed that populations of Eleutheronema tetradactylum living in geographic proximity to one another are more similar than conspecifics living farther apart. Key words: Fourfinger Threadfin %Eleutheronema tetradactylum %Persian Gulf %Truss network INTRODUCTION threadfish (family Carangidae). Their bodies are Fourfinger Threadfin is silvery grey perciform marine separate. Their tail fins are large, unequal and deeply fish of the family Polynemidae(Figure 1)[1]. forked; this is an indication of their speed and agility. This name comes from the four short filaments that The mouth is large and inferior; a blunt snout feature on the pectoral fin. Found in tropical to projects far ahead. The jaws and palate possess bands of subtropical waters throughout the world(Indo-West villiform (fibrous) teeth.Uupper sides of head and trunk Pacific, from the Persian Gulf east to Papua New Guinea with slight darkish silver tinge, becoming lighter on lower and northern Australia-Figur 2)[2]. sides. Anterior margins of first and second dorsal fins It occur mainly over shallow muddy bottoms in blackish, remaining parts translucent and slightly coastal waters, also enter rivers. Fed on prawns and fish blackish, respectively; pectoral fin vivid yellow (dusky (largely members of Mugilidae, Engraulidae and yellow in large specimens over ca. 350 mm SL). Maximum Sciaenidae) with occasional polychaetes. Frequency of length about 200 cm. Sex changing male to female with crustaceans to fish in the diet varies seasonally. Larvae growth. Juveniles found in estuaries. During winter, (7-30 mm TL) feed mainly on copepods and mysids, but adults ascend the rivers, although larger fish are more also take shrimps and prawn larvae. Juveniles (31-60 TL) often observed in pairs or singly. Threadfins are both fed on prawns shrimps and mysids.Threadfin family important to commercial fisheries as a food fish and contains nine genera and 33 species. An unrelated popular among anglers. Their habit of forming large species sometimes known by the name threadfin, schools makes the threadfins a reliable and economic Alectis indicus, is properly known as the Indian catch [3,4]. fusiform, with spinous and soft dorsal fins widely