Synidotea harfordi Benedict, 1897

Hendrickx, Michel E., 2018, Notes on two shallow water isopods (Crustacea: Peracarida: Isopoda: Idoteidae) from Kino Bay, Gulf of California, Mexico, Nauplius (e 2018027) 26, pp. 1-7 : 2-3

Synidotea harfordi Benedict, 1897

( Fig. 1 )

Idotaea marmorata Harford, 1877: 117 .

Synidotea harfordi Benedict, 1897: 402 , fig. 13. — Richardson, 1899a: 849. — Richardson, 1899b: 269. — Richardson, 1905: 387–388, figs. 427–428. — Johnson and Snook, 1927:290. — Schultz, 1969: 67. — Menzies and Miller, 1972: 16–18, fig. 6. — Brusca and Wallerstein, 1979: 260–261, fig. 3, 269 (key). — Austin,1985:581. — Espinosa-Pérez,1999: 156. — Espinosa-Pérez and Hendrickx, 2001: 50 (list). — Espinosa-Pérez and Hendrickx, 2006:242. — Brusca et al., 2001: 31 (list), fig. 91. — Brusca et al., 2005: 137 (list).

Synidotea hartfordi . — Wallerstein, 1980: 338. — Vargas et al., 1985: 234.

Material examined. Alcatraz Island , Kino Bay (28°48’56”N 111°57’51”W), Sonora, Mexico, 25 males (TL 7.8–20.6 mm) and 21 ovigerous females (TL 11.1-13.3 mm), 8 March 2007, 0.5–1.2 m depth, among sea grasses (ICML-EMU-12093) .

Distribution. Magdalena Bay (type locality). Oregon and Morro Bay, California, USA. Cedros Island, Baja California, Mexico.Gulf of California, Mexico: Chivato Point, near Santa Rosalia, Baja California Sur; Estero del Soldado, Guaymas, and Bacochibampo, Sonora; Chamela, Jalisco; Acapulco, Guerrero. Gulf of Nicoya, Costa Rica (a single record). Introduced in Japan ( Richardson, 1905; Menzies and Miller, 1972; Brusca and Walerstein, 1979; Vargas et al., 1985; Espinosa-Pérez, 1999; Brusca et al., 2001, 2005).

Remarks. The illustration by Richardson (1905; dorsal view and maxilliped) was of poor quality. Menzies and Miller (1972) provided a detailed series of illustrations of S. harfordi , including a dorsal view, and figures of pereopods 1 and 7, buccal appendages (mandible, maxilla 1 and 2, maxilliped), appendix masculina, and pleopods 1 and 2. Other illustrations were provided by Brusca and Wallerstein (1979, dorsal view and maxilla 2), and Brusca et al. (2001; dorsal view), but were not very detailed.

The material examined herein ( Fig. 1 ) fits well the description of Menzies and Miller (1972). Pairs of setae illustrated on the last antenna 1 article ( Fig. 1B ) by these authors are aesthetascs. With a total of 46 specimens collected in a single seagrass sample during this study, S. harfordi does not appear to be as uncommon as previously reported for the Gulf of California ( Brusca & Wallerstein, 1979), at least in its northern part. Males and females were found in roughly the same number, and all females were ovigerous. Menzies and Miller (1972) emphasize that the thermal distribution of S. harfordi ranges from warm-temperate to colder waters at 34°30’N. Therefore, the presence of this species in Kino Bay, where shallow-water summer temperatures can be in the range of 25−30°C, is noteworthy.

Figures

Figure 1.Synidoteaharfordi Benedict,1897,male,TL18.9 mm.A.Dorsal view.B.Detailof antenna1,dorsal.C.Detailofcephalon,lateral..