Pisidia inaequalis ( Heller, 1861 )

Werding, Bernd & Hiller, Alexandra, 2007, The Porcellanidae (Crustacea: Decapoda: Anomura) of the Red Sea with description of a new species of Petrolisthes, Zootaxa 1460, pp. 1-24 : 17-18

16. Pisidia inaequalis ( Heller, 1861)

( Fig. 16 )

Porcellana inaequalis Heller, 1861: 259 , pl. 2, fig. 7.

Pisidia inaequalis .— Lewinsohn 1969: 153, figs. 34a–k.— Haig 1978: 707.— Hogarth 1988: 1102.

Material examined. 1 ɗ ( SMNS ZIa 3376), Red Sea, Egypt, Koseir, leg. Klunzinger; Red Sea, Sudan, Sanganeb Atoll ( SMF), 1 ɗ, 1 Ψ (ov), ( SMF 25657), 28 Mar. 91, S-Jetty, 2m, SAN 20, in dead Stylophora pistillata ; 1 Ψ (ov), ( SMF 25660), 28 Mar. 91, at Wrack der SAIDA III, 5 m, SAN 39, in dead Seriatopora hystrix ; 2 ɗ, 2 Ψ (ov), ( SMF 25656), 29 Mar. 91, S-Jetty, E- side, lighthouse, 1 m, SAN 14, in living Pocillopora damicornis ; 16 Ex., ( SMF 25661), 30 Mar. 91, S-Jetty, E- side, lighthouse, 1m, SAN 51, in dead Stylophora pistillata ; 16 ɗ (1 Bopyr), 21 Ψ (18 ov), 1 juv., ( SMF 25654), 4-15 Apr. 91, S-Jetty, E-Seite, 1m, SAN 12, in dead Stylophora pistillata ; 8 Ex., ( SMF 25658), 4-15 Apr. 91, S-Jetty, E-Seite, 1m, SAN 37, in living Stylophora pistillata ; 51 Ex., ( SMF 25652), 5 Apr. 91, S-Jetty, E-Seite, 1m, SAN 3, in dead Stylophora pistillata ; 2 ɗ, 1 Ψ (ov), ( SMF 25651), 6 Apr. 91, S-Jetty, W-Seite, 1m, SAN 2, in living Stylophora pistillata ; 10 Ex., ( SMF 25653), 6 Apr. 91, S-Jetty, West side, SAN 8, in dead Stylophora pistillata ; 55 Ex.; ( SMF 25655), 8 Apr. 91, N-Jetty, West side, 1 m, SAN 13, in dead Stylophora and under stones; 2 ɗ, 3 Ψ, ( SMF 25659), 8 Apr. 91, N- Jetty, West side, 1 m, SAN 38, in dead Stylophora pistillata ; 1 Ψ (ov), 20 Sep. 92, ( SMF 25673), Wingate Reef, 5m, SAN 171, in living Pocillopora ; 18 Ex., ( SMF 25670), 21 Sep. 92, 1 m, SAN 154, in dead Stylophora ; 2 ɗ, 1 Ψ (ov), ( SMF 25671), 21 Sep. 92, Wingate Reef, 5m, SAN 166, in dead corals; 3 Ψ (2 ov), 1 juv., ( SMF 25672), 28 Sep. 92, Wingate Reef, 4m, SAN 169, inner reef, in dead Pocillopora ; 12 ɗ, 1 Ψ (ov), ( SMF 25668), 27 Sep. 92, on margin of atolls, 1 m, SAN 145, in dead Pocillopora ; 3 ɗ, 4 Ψ (ov), ( SMF 25669), 27 Sep. 92, on margin of atolls, 1m, SAN 152, in living Pocillopora and Acropora ; 1 ɗ, 1 Ψ (ov), ( SMF 25666), 25 Sep. 92, 1 m, SAN 133, in living Stylophora , leg. Hamza; 4 ɗ, 2 Ψ (1 ov), ( SMF 25665), 29 Sep. 92, N-Jetty, SAN 127, in dead Stylophora , leg. Hamza; 4 ɗ, 8 Ψ (ov), 5 juv., ( SMF 25667), 29 Sep. 92, N-Jetty, laguna border, 1 m, SAN 138, in dead Pocillopora ; 6 Ex. (severely damaged), ( SMF 25662), 30 Sep. 92, N-Jetty, 1 m, SAN 103, in living Acropora , leg. Hamza; 1 ɗ, 1 Ψ, 2 Ex. (with Rhizocephala), ( SMF 25663), 2 Oct. 92, S-Jetty, SAN 105, 1 m, in dead Pocillopora , leg. Hamza; 5 ɗ 4 Ψ ( SMF 25664), 30 Sep. 1992, S-Mole, 2 m, SAN 119, from living Acropora , leg. V. Neumann; 1 ɗ ( ZMB 19478c), Red Sea, Sinai coast; 1Ψ ( ZSM 175/1), Red Sea, Sinai, Tor, leg. Hartmayer.

Measurements. Largest ɗ 3.0 x 2.9 mm; largest Ψ 3.0 x 2.9 mm.

Remarks. Pisidia inaequalis was found in all 1–5 m depth samples obtained during the reef studies in Sanganeb-Atoll, and almost exclusively in living and dead corals. With the exception of one specimen of Petrolisthes aegyptiacus n. sp., all specimens representing other species from this atoll were found only in three samples from 20–50m depth. This finding confirms Lewinsohn’s (1969) observation: “This minute species is perhaps the most common porcellanid on coral reefs of the Red Sea. It occurs here from the intertidal to a few meters of depth.”

Distribution. Red Sea, Gulf of Aden, and Persian Gulf.

Figures

FIGURE 16. Pisidia inaequalis (Heller, 1861), male, Egypt, Red Sea, Sanganeb Atoll (SMF 25668).