Sylviocarcinus australis Magalhães & Türkay, 1996

Collins, Pablo A., Giri, Federico & Williner, Verónica, 2009, Range extension for three species of South American freshwater crabs (Crustacea: Decapoda: Trichodactylidae), Zootaxa 1977, pp. 49-54 : 52

Sylviocarcinus australis Magalhães & Türkay, 1996

( Fig. 1 c)

Sylviocarcinus australis (Magalhães & Türkay 1996) — Magalhães and Türkay (1996b): 238 p., fig. 129 (complete synonymy).

Diagnosis. Each anterolateral border of carapace: four distinctive teeth. Abdominal segments III–VI: fused. Male plp 1: subdistal lobe poorly developed with a subterminal spine field. Basal lobe: more important than in the other crabs ( Fig. 1 c).

Habitat. This species was observed in environments similar to those of S. pictus and Z. collastinensis , using caves and tree trunks. Some crabs were also observed within aquatic vegetation, mainly of the Paspalum genus.

Material examined. Eleven male and four female specimens; carapace width: 41.8 mm (SD 5.38). Two males and one female, FANM N° MFA – ZI – N° 348, Salado River ( Argentina, Santa Fe, Santo Tomé, 31°39’S 60°45’W), without collection date, Collins coll.; two males and one female, ML-INALI N° 12, Ubajay stream ( Argentina, Santa Fe, Rincón, 31°37’S 60°36’W), 1.12.0 5, Collins coll.; three males and one female, ML-INALI N° 13, San Javier River ( Argentina, Santa Fe, 29°13’S 59°35’W), 30.11.0 5, Collins coll.; three males and one female, ML-INALI N° 18, Malabrigo stream ( Argentina, Santa Fe, 29°26’S 59°45’W), 30.11.0 5, Collins coll.; one male, ML-INALI N° 18, Paraná Mini stream ( Argentina, Santa Fe, Villa Ocampo, 28°32’S 59°15’W), 29.11.0 5, Collins coll.

Southern locations. Ubajay stream (31°36’S 60°34’W), Salado River (31°39’S 60°45’W), Paraná River floodplain, Argentina.

New distribution. Paraguay, Brazil and Argentina, Coronda River south limit (31°57’ S 60° 54’W) ( Fig. 2 c).

Figures

FIGURE 1. Right male pleopod 1, mesial aspect of A) Dilocarcinus septemdentatus, together with ventral view of the carapace with the abdominal segments (A’), B) Sylviocarcinus pictus, and C) S. australis, all from specimens from the Paraná River, Argentina. Scale bar equals 1.0 mm.

FIGURE 2. Distribution maps of Dilocarcinus septemdentatus, Sylviocarcinus pictus and S. australis according to Magalhães and Türkay (1996 a; b); Magalhães (1998; 1999 a; b; 2000); Morrone and Lopretto (2001). Dots, locations; drawn lines, distribution known to date; brown lines, newly reported distribution areas.