PHYLOGENETIC ANALYSIS OF Sphaerirostris picae (ACANTHOCEPHALA: CENTRORHYNCHIDAE) BASED ON LARGE AND SMALL SUBUNIT RIBOSOMAL DNA GENE

The purpose of the present study was to add new 18S and 28S DNA gene sequences data to Sphaerirostris picae (Rudolphi, 1819) Golvan, 1960 and analyze the generated sequences to define the taxonomic placement of genus Sphaerirostris and providing a better resolution inside the Palaeacanthocephala. Two regions: 18S and 28S of nuclear ribosomal DNA of S. picae were amplified using polymerase chain reaction and sequenced following the instructions of GATC German company facility. Mealign module in the DNAStar Lasergene V7 was used to design a forward and reverse primer of 28S DNA gene. 18S and 28S DNA gene sequences of S. picae were aligned with sequences for both genes of Palacanthocephalans retrieved from GenBank. Results were analyzed using distance matrix methods UPGMA. The resulting phylogenetic trees suggest a paraphyletic arrangement of the two Palaeacanthocephala orders; Echi- norhynchida and Polymorphida depending on the placement of the three echinorhynchids, Transvena, Rhadinorhynchus and Gorgorhyn- choides in the polymorphid clade. The present study is the first to generate gene sequences of genus Sphaerirostris and discuss its rela- tionships within Palaeacanthocephala. Further comprehensive studies should be done for other species of genus Sphaerirostris and fami- ly Centrorhynchidae as all based on molecular phylogenetic analysis to solve their taxonomic overlapping.