Aplysina (Porifera: Demospongiae) species identification through SSCP-ITS patterns

Abstract

Keratose sponges have no spicules and limited robust morphological characters, causing severe problems for taxonomic classification. Single-strand conformational polymorphism (SSCP) analysis of PCR amplified internal transcribed spacers (ITS) of nuclear ribosomal RNA (rRNA) genes was used to elucidate speciation patterns in marine sponges of the genus Aplysina. In this study, Aplysina species with non-ambiguous traditional morphological alpha taxonomy were used to generate standard SSCP-ITS patterns, which were compared with patterns from alleged new species. Our results show that ITS-SSCP patterns allowed the differentiation of Aplysina sponges, demonstrating the advantage of a method that explores the secondary structure compared to direct sequencing.