Craniometric and genetic diversity of striped dolphins, Stenella coeruleoalba (Meyen, 1833), in the Adriatic sea

Plavobijeli dupin, Stenella coeruleoalba (Meyen, 1833), je najučestalija vrsta kita u Sredozemnom moru. Populacija koja nastanjuje Sredozemno more klasificirana je prema IUCN-u kao osjetljiva. Smatra se da nije rezidentna vrsta Jadrana te je ovo istraživanje tek drugo na temu plavobijelih dupina Jadrana. U radu su analizirane kraniometrijske osobitosti plavobijelih dupina iz hrvatskog dijela Jadrana i uspoređene s plavobijelim dupinima drugih mora. Napravljena je analiza haplotipova kontrolne regije mitohondrijske DNA plavobijelih dupina Jadrana, 17 po prvi puta analiziranih i deset iz prijašnjeg istraživanja, te šest iz Ligurskog mora za usporedbu. Analizom 37 kraniometrijskih mjera 30 lubanja utvrđeno je da mužjaci imaju dulji rostrum, veći broj zubiju, šire zube te veće posttemporalne jame od ženki, dok ženke imaju veći neurokranij, očnice i hoane. Prema kraniometrijskim vrijednostima plavobijeli dupini iz hrvatskog dijela Jadrana slični su onima iz talijanskih voda i manji od onih iz japanskog dijela Tihog oceana. Na 27 uzoraka mtDNA iz Jadrana utvrđeno je devet haplotipova koji se razlikuju u 32 polimorfna mjesta. Haplotipska raznolikost iznosi 0,832, a nukleotidna 0,00729, što ukazuje na veliku genetičku raznolikost plavobijelih dupina Jadrana. Jedan uzorak iz Ligurskog mora pripadao je haplotipu pronađenom u Jadranskom moru, dok je svaki od preostalih pet pripao jednom od pet novo-utvrđenih haplotipova.Striped dolphin, Stenella coeruleoalba (Meyen, 1833), is the most abundant cetacean species in the Mediterranean Sea. The population that inhabits the Mediterranean is classified as vulnerable by IUCN. It is considered a nonresident species in the Adriatic Sea and this is the second research on striped dolphins from the Adriatic. In this thesis we analyze the craniometric characteristics of striped dolphins from the Croatian part of the Adriatic and compares them to striped dolphins of other seas. An analysis of haplotypes of the control region of mitochondrial DNA of striped dolphins from the Adriatic was conducted, 17 samples were analyzed for the first time and ten were added from a previous research. Six samples from the Ligurian Sea were analyzed for comparison. Analysis of 37 craniometrical features on 30 skulls revealed that males have a longer rostrum, greater number of teeth, wider teeth and bigger temporal fossae than females, while females have a greater neurocranium, orbital bones and internal nares. When compared by craniometrical values, striped dolphins from the Croatian part of Adriatic are similar to those from Italian waters and smaller than those from the Japanese part of the Pacific Ocean. Nine haplotypes were found among 27 mtDNA samples from the Adriatic, differing in 32 polymorphic sites. Haplotype and nucleotide diversity were 0,832 and 0,00723, respectively, which indicates great genetic diversity of striped dolphins from the Adriatic. One sample from the Ligurian Sea belongs to a haplotype found in the Adriatic, while each of the other five belong to one of the five newly-found haplotypes