A genus recognised from the warm temperate and cold temperate waters of Brazil, Uruguay and Argentina. Fossil species are recognised from the Miocene of Brazil and Argentina.
The type species is Porphyria urceus Röding, 1798.
The following extant species are recognised:
Sumbauma (12°15’S; 37°47’W), Bahia state, Brazil to Puerto Lobos (42°00’S; 65°04’W), San Matías Gulf, Chubut province, Argentina in 0–53 m depth.
RV 7306. Brazil, Sao Paulo, Pereque, trawled offshore, depth 3-4.5 m, sand bottom. Scale bar is 1 cm.
Maricá (22°55’S; 42°49’W), Rio de Janeiro state, Brazil to Villarino (42°25’S; 64°31’W), Río Negro province, Argentina in 0–26 m depth.
RV 1997b. Argentina, Villa Gesell, in shallow water on sand. Scale bar is 1 cm.
Chuí (33°44’S; 53°21’W), Rio Grande do Sul State, Brazil to La Coronilla (33°53’S;53°30’W), Rocha Department, Uruguay, usually intertidal or in the surf zone.
RV 2002. Brazil, Rio Grade do Sul, Barra do Chui, on sand, shallow water, February 1988. Scale bar is 1 cm.