The metazoan parasite communities of the Argentinean sandperch Pseudopercis semifasciata (Pisces: Perciformes) and their use to elucidate the stock structure of the host

Abstract

The use of parasites as biological tags allowed the identification of 3 stocks of Argentinean sandperch, Pseudopercis semifasciata (Cuvier), in the Argentine Sea. A total of 100 specimens caught in 3 zones: Villa Gesell (37 degrees 15'S, 57 degrees 23'W; n=20), Miramar (38 degrees 03'S, 57 degrees 30'W-38 degrees 44'S, 58 degrees 44'W; n=30) and Península Valdes (42 degrees 00'-42 degrees 45'S; n=50), were examined and 28 parasite species were found, 15 of them being new host records. Both univariate and multivariate analyses identified discrete stocks in each zone. The observed differences were not related to the host size or sex. Each locality was characterized by its own indicator species. Villa Gesell was typified by unidentified cestode plerocercoids, Corynosoma cetaceum and Hysterothylacium sp., Miramar by Heterosentis sp. and Pseudoterranova sp. and Península Valdes by A. simplex s.l. Fishes from both northern localities shared gnathiid pranizae, Corynosoma australe and Grillotia sp. as indicators, whereas Miramar and Península Valdes shared only Trifur tortuosus. The most distant localities showed no indicator species in common. Discriminant analyses of parasite assemblages agreed with populational comparisons in identifying the same set of biological tags, whereas some differences in the identity of indicator species were obtained by similarity analysis. However, the 3 approaches were congruent in identifying Grillotia sp., C. australe and C. cetaceum as indicators of northern localities, and A. simplex s.l. as related to Patagonian waters. Differences among zones could be enhanced by the sedentary habits, limited dispersal and high site fidelity of P. semifasciata, and their spawning in rocky outcrops, which are isolated environments.

A checklist of marine larval trematodes (Digenea) in molluscs from Argentina, Southwestern Atlantic coast

“…However, the number of cercariae identified at generic (10) or specific level (6) is relatively small in comparison with a great number of adults digenean known (226) from vertebrates hosts, 125 from fish (e.g., Kohn et al 2007;Braicovich and Timi 2008;Timi et al 2008;Timi and Lanfranchi 2009), 95 from birds (e.g., Lunaschi et al 2007;Diaz and Cremonte 2010) and six from marine mammals (e.g., Lunaschi et al 2007). However, from Argentina, there are few species of molluscs recorded (20) with digenean larvae, despite that the diversity of Argentine marine molluscs is high (849 species) (Miloslavich et al 2011).…”

Parasites of a marine benthic fish in the Southwestern Atlantic: searching for geographical recurrent patterns of community structure

“…In fact, C. australe, Grillotia sp., Nybelinia sp. and S. polymorphus have been always recorded at higher abundance and prevalence in Bonaerense waters in relation to Patagonian ones, in all fish species analyzed comparatively between these zones, whereas A. simplex and H. aduncum showed the opposite pattern (Timi 2003;Sardella and Timi 2004;Timi et al 2008;Timi and Lanfranchi 2009b). These differences between zones can be due to the influence of environmental conditions on the fitness of parasite species, as well as on the biota in general, and consequently, on the distribution of other hosts for these species.…”

“…In fact, discrete populations, discriminated by their parasites, have been recorded for other host species in the Bonaerense zone (Timi and Lanfranchi 2009b;Timi et al 2009). Furthermore, C. australe displays higher values of abundance in several host species in the northern boundaries of this region (Timi 2003;Braicovich and Timi 2008;Timi and Lanfranchi 2009b;Timi et al 2009Timi et al , 2010. The notably higher levels of parasitism by C. australe could indicate that these samples come from this zone.…”

Parasites as biological tags for stock identification of blackspot seabream, <i>Pagellus bogaraveo</i>, in Portuguese northeast Atlantic waters

“…Indeed, many stock identification studies have successfully used juvenile acanthocephalans such as Corynosoma sp. (Timi andLanfranchi 2009, McClelland andMelendy 2011), Bolbosoma vasculosum ) and Bolbosoma sp. (George-Nascimento and Arancibia 1992) as biological tags.…”