Family Plagusiidae Dana, 1851

Percnon gibbesi (H. Milne Edwards, 1853)

Diagnosis: Melo, 1996:457.

Previous records: Pocock, 1890:513 [as Leiolophrus planissimus (Herbst, 1804)]; Coelho, 1967 /69: 235 [as Percnon planissimum (Herbst, 1804)]; Coelho and Ramos, 1972:204 [as Percnon planissimum (Herbst, 1804)]; Williams, 1984:462; Melo, 1996:457, 1998:500; Coelho et al., 2002:445.

Examined material: JAN/92: Praia do Porto, 1 female. MAR/92: Praia da Atalaia, 1 male, 1 female. JUN/ 92: Praia da Conceição, 2 males, 1 female. AUG/92: Praia da Caieira, 6 specimens. DEC/92: Baía do Sueste, 4 specimens. JAN/2000: Praia da Caieira: 2 females.

Habitat: On and under rocks; in caves; on seaweed; always in the sublittoral.

Observations: Generally seen in groups; coloration brown with fluorescent blue spots.

Plagusia depressa (Fabricius, 1775)

Diagnosis: Melo, 1996:458.

Previous records: Pocock, 1890:513; Crosnier and Forest, 1966:93; Coelho and Ramos, 1972:204; Fausto Filho, 1974:15; Williams, 1984:463; Melo, 1996: 458, 1998:500.

Examined material: JAN/92: Praia do Leão, 1 female; Praia da Atalaia, 1 male. JUN/92: Praia do Porto, 1 male. AUG/92: Praia da Atalaia, 1 female. DEC/92: Praia do Boldró, 4 specimens. MAR/93: Praia do Leão, 6 specimens. JAN/2000: Praia do Leão: several exuvias.

Habitat: On rocks; in rocky-slimy bottom.

Observations: very abundant species, observed in the intertidal and sublittoral zones, and in between the tide lines.