New record of diamondback puffer Lagocephalus guentheri Miranda Ribeiro , 1915 from the North-Eastern Mediterranean , Turkey

One specimen of the diamondback puffer fish, Lagocephalus guentheri (33.7 cm, TL) was caught by a commercial trammel net at a depth of 37 m on 12 May 2017 from the Arsuz coast, Turkey. The present paper is the first report of L. guentheri from the eastern Mediterranean coast of Turkey. Morphometric and meristics characters of our specimens are given and some remarks about the geographical distribution of the species in the all around the Mediterranean is presented. Although L. guentheri is recorded in the Mediterranean Sea and have been reported from the North-eastern Aegean waters of Turkey. The present study, L. guentheri was recorded for the first time from the northeastern Mediterranean, Turkey (Iskenderun Bay). The present of this species in the Mediterranean is propably due to migration from the Red Sea via the Suez Canal.

The diamondback puffer, Lagocephalus guentheri is found from the Indo West Pasific to the Red Sea and Southwest Atlantic.This species usually occur in shallow waters (Frose & Pauly, 2017).
In 2015, the first report of L. guentheri from the Mediterranean Sea was reported from Egypt waters (Farrag et al., 2016) and then the presence of the species in Turkey was confirmed with a single record from Çandarlı Bay, İzmir in the northern Aegean Sea (Akyol & Aydın, 2016).
To date several alien puffer fish species that have penetrated the Mediterranean Sea via the Suez Canal and Straits of Gibraltar (Bilecenoglu, 2003;Akyol et al., 2005;Turan et al., 2010;Erguden et al., 2011;Turan & Yaglioglu, 2011).These alien species rapidly dispersed throughout the Mediterranean Sea (Ragonese et al., 1997;Quignard & Tomasini, 2000) and it is presently considered as frequent in the western basin and in large areas of the eastern basin (Golani et al., 2002;Turan et al., 2010).The increase in water temperature has been considered as the main reason for the increasing introductions of alien fish species in the Mediterranean Sea (Ben Rais Lasram et al., 2010, Golani, 2010, Turan et al., 2016).
Although L. guentheri is recorded in the Mediterranean Sea and have been reported from the North-eastern Aegean waters of Turkey, in the present study, L. guentheri was recorded for the first time from the northeastern Mediterranean coast of Turkey (Iskenderun Bay).

Material and Methods
On 12 May 2017, one specimen diamondback puffer, L. guentheri was captured from Arsuz coast (Iskenderun Bay, northeastern Mediterranean Sea) (Figure 1).The specimens were obtained by a commercial trammel net at a depth of 37 m on sandy and rocky bottoms.This specimen preserved in 4% formalin and were deposited in the Museum of the Faculty of Marine Sciences and Technology, Iskenderun Technical University, (MSM-PIS/2017-1) (Figure 2).All morphometric measurements were measured to the nearest 0.01 mm using digital calipers.All counts and measurements,and the morphological description and colour of the diamondback puffer agree with descriptions Matsuura et al. (2011), Farrag et al. (2016) and Akyol et al. (2016).Sex was determined by macroscopic examination of the gonad.

Results
The distinguishing meristic and morphometric characteristics of the specimen are given and comparison other previous record in Table 1.The specimen is a mature fish measuring in total length 33.7 cm and 565.8 g in weight.The Mediterranean specimen of L. guentheri is described as follows: Body is relatively elongate, broad, head; two lateral lines with no spots.Eyes are large rounded with an orbital edge atlower part.Head and belly with trough spinules extending posteriorly to the lower jaw and slightly to before the anus.Spinules on the back forming a rhomboidal patch and spinule patch that extends posteriorly to the region dorsal to the posterior part of the pectoral fin and also the middle part of the caudal fin slightly produced posteriorly.
In fresh specimen, the colour is yellow-brownish or dark green yellowish with dark bands over the back, the first band between the eyes, the second above the gill opening, the third above the posterior part of the pectoral fin, the fourth encircling the dorsal fin base.The dorsal fin dusky, pectoral and anal fins pale,the caudal fin is lunate and dark brown with white dorsal and ventral tips.

Discussion
To date four species of the genus Lagocephalus are known from the Red Sea.L. guentheri is closely related to L. spadiceus and L. gloveri.According to Matsuura et al. (2011) L. guentheri is similar to L. spadiceus in the shape of the caudal fin and another similar species of L. gloveri in the colour of the pectoral fin.Matsuura et al. (2011) reported these three species are only distinguished from each other by their shape of caudal fin and colour of caudal fin and pectoral fin.The caudal fin in L. spadiceus has a slightly lunate where as the caudal fin in L. guentheri has a slight posterior extension medially that makes the fin appear to be doubly emarginate.Besides, differs caudal coloration in L. guentheri; the caudal fin is dark brown or almost black excepting the dorsal and ventral white tips, but in L. spadiceus; the dorsal two-thirds of the caudal fin are dark yellow and the ventral one-third is white.However, L. guentheri is similar to L. gloveri in the colour of the pectoral fin.The pectoral fin of the former is pale in L. guntheri whereas the colour of pectoral fin is dusky in L. gloveri.
Table 1.Measurements and counts of Lagocephalus guentheri compared with previous record caught from Candarli Bay, Aegean Sea (Akyol & Aydın, 2016) and the Red Sea (Matsuura et al., 2011).Morphometric measurements as proportions are given in paranthese Although, description of Matsuura et al. (2011) indicates clear differences between L. guentheri and L. spadiceus, and L. guentheri in this study first confirmed record from eastern Mediterranean, Turkey with this report, the number of Lagocephalus species in the Mediterranean Sea reach to five.However, according to Matsuura et al. (2011) previous records of L. spadiceus in the Red Sea and Mediterranean Sea are probably misidentification and need to be again reconfirmed.Thus, further morphologic and genetic studies are needed to confirm whether L. spadiceus occurs in the Mediterranean.
This study also reports the longest maximum total length of L. guentheri or entire Mediterranean Sea.Randall (1995) reported that maximum total length of L. guenheri for males/unsexed as 26.0 cm in Mediterranean.The present study showed that the maximum total length for females as 33.7 cm (Table 1).However, this study is the first report on maximum length for L. guentheri for females in Mediterranean coast of Turkey.