Cryptic species of Didymobothrium rudolphii (Cestoda : Spathebothriidea) from the sand sole, Solea lascaris, off the Portuguese coast, with an analysis of their molecules, morphology, ultrastructure and phylogeny

• Type: Article in International Scientific Journal
• Date: 2007

Authors

Marques, JF (Author) Other; Santos, MJ (Author) FCUP; Gibson, DI (Author) Other; Cabral, HN (Author) Other; Olson, PD (Author) Other

Journal

Title: Parasitology

Vol. 134 No. 7

Pages: 1057-1072

ISSN: 0031-1820

Publisher: Cambridge University Press

Indexing

ISI Web of Knowledge - 18 Citations

ISI Web of Science

Scopus - 21 Citations

Scientific classification

FOS: Medical and Health sciences > Health sciences

Other information

Authenticus ID: P-004-974

DOI: 10.1017/s0031182007002491

Abstract (EN): Didymobothrium rudolphii (Cestoda: Spathebothriidea) was collected seasonally from the sand sole, Solea lascaris, off the northern, central and Southern areas of the Portuguese coast. Morphological and molecular analyses were conducted in order to examine the possible existence of cryptic species and to facilitate the circumscription of their morphological boundaries. Data were compared between D. rudolphii specimens from each of the 3 geographical areas and 4 seasons, and principal components analysis of 18 morphological characters was used to detect differences. Two distinct genotypes were present with sequence divergences of 1 center dot 9%. and 2 center dot 1%, in the large Subunit (lsrDNA) and second internal transcribed spacer (ITS-2) of ribosomal DNA (rDNA), respectively. The less common 'central' genotype was present only off the central area from summer to winter, whereas the 'common' genotype was present throughout the year off the northern and southern areas, but only during spring in the central area, No sequence variation was found within each genotype. The presence of 2 distinct genetic entities was supported by morphological analyses, which showed the 'central' genotype specimens to be more slender and elongate, although morphometric ranges overlapped considerably for most characters. Molecular phylogenetic analysis of 4 of the 3 known genera of the Spathebothriidea showed Spathebothrium to be the earliest branching lineage and the 2 genotypes of Didymobothrium formed a sister group to Cyathocephalus. The concordance of genetic differences with variation in host diet according to season and locality could account for sympatric speciation occurring in the central region of the Portuguese coast.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 16