Diversity of Gordiida (Nematomorpha) in the Diamante River basin and their epibionts.

ZANCA F.

Richmond, Virginia

Congreso; 87th Annual Meeting of The American Society of Parasitologists (ASP). 2012 First International Nematomorpha Symposium. Organizado por the American Society of Parasitologists (ASP); 2012

the American Society of Parasitologists

Diversity of Gordiida (Nematomorpha) in the Diamante River basin and their epibionts. The Diamante River basin is one of the hydrogeological basins usedfor irrigation purposes(irrigation, industry, consumer population) located southof the Province of Mendoza, Argentina. So far, only two species of Gordiida were registered from the north of the province in Chacras de Coria: Beatogordius irregularis and Paragordius varius. The biodiversity of Gordiida in the Diamante River basin, the intraspespecific variation and their epibionts are here studied. All the collection sites were georeferenciated and temperature and pH were registered. All male specimens were fixed in ethanol 70º at the site of collection and the females were reserved the offspring´s birth. The study was carried out under optical microscopy and scanning electron microscopy, with and without previous washes. Sections of the mid-body (5mm) of each specimen were cut. For identification under optical microscopy the gordiid tissues were removed with (OH) Na 5M during 3-5 minutes and then observed. In order to identify the gordiid species and their epibionts by scanning electron microscopy, all the pieces washed and not washed, were critical point dried and observed. Shannon index and density of epibionts were calculated. The collection comprised 43 males, 15 Pseudochordodes gordioides, 13 Pseudochordodes bedriagae, 13 Noteochordodes talensis, 1 Noteochordodes cymatium and 1 Neochordodes occidentalis, and 2 females of P. gordiodes. The specific diversity was 1,26. All the epibionts belong to the genus Cocconeis (Bacillariophyta). The morphology data of P. gordioides larvae are presented. The intraspecific variation and the importance of adding new characters like larval morphology and DNA sequence data in order to identify species of Gordiida will be discussed.