Sylviocarcinus pictus (Milne-Edwards, 1853)

(Fig. 1 b)

Sylviocarcinus pictus (Milne-Edwards, 1853) — Magalhães & Türkay 1996b: 244 p., fig. 135 (complete synonymy).

Diagnosis. Carapace: 4 distinctive teeth on each anterolateral border. Abdominal segments III–VI of male: fused. The male plp 1 bends following a regular curve to the right, subdistal lobe with subterminal spine field strongly developed, basal lobe: insignificant (Fig. 1 b).

Habitat. This species was observed in caves and under tree trunks. In other caves, the crab Zilchiopsis collastinensis was mainly found.

Material examined. Seven males, one female and eight juveniles; carapace width: 43.5 mm (SD 6.68) two males, one female and four juveniles, FANM N° MFA - ZI - N° 271, Santa Fe stream (Argentina, Santa Fe, 31°38'S 60°39'W), 22.3.65, non-specific collector; two males and four juveniles, ML-INALI N° B - 9, Coronda River (Argentina, Santa Fe, Sauce Viejo, 31°48'S 60°46'W), 13.12.0 0, Collins coll.; one male, ML- INALI N° B 10, Setúbal Lagoon (Argentina, Santa Fe, Colastiné Sur, 31°39'S 60°45'W), 20.12.0 0, Collins coll.; one male ML-INALI N° B 11, Salado River (Argentina, Santa Fe 31°39'S 60°45'W), 12.2.0 3, Regner coll.; one male, ML-INALI N° B 15, El Limpio stream (Argentina, Santa Fe, Paranacito, 28°5’S 59°09’W), 29.11.0 5, Collins coll.

Southern locations. Setúbal lagoon (31°35'S 60°39'W), Coronda River (31°48'S 60°46'W) and Salado River (31°39'S 60°45'W), Paraná River floodplain, Argentina.

New distribution. Peru, Guyana, French Guyana, Paraguay, Bolivia, Brazil and Argentina, Coronda River south limits (31°48’S 60°46’W) (Fig. 2 b).