Oxycephalus clausi Bovallius, 1887

Gasca, Rebeca & Hendrickx, Michel E., 2022, Pelagic amphipods (Crustacea: Amphipoda: Hyperiidea) in western Mexico. 7 Superfamily Platysceloidea. Family Oxycephalidae, Zootaxa 5105 (2), pp. 219-236 : 223-224

Oxycephalus clausi Bovallius, 1887

Oxycephalus clausi Bovallius, 1887: 35‒36 ; Brusca, 1981: 12 (list), 33 (key), 44‒45, fig. 20a, 20e; Siegel Causey, 1982: 330 (key), 331; Vinogradov et al., 1996: 504, fig. 219; Zeidler, 1999: 394 (key), 411‒416, figs. 1C, 12‒15; 2016: 73 (passim), 76 (key); García Madrigal, 2007: 157 (list); Guillén Pozo, 2007: 18 (key), 98‒100, fig. 34; Valencia & Giraldo, 2009: 268 (tab. 1); 2012: 1493 (tab. 1); Gasca, 2009: 89 (tab. 1); Lavaniegos & Hereu, 2009: 142 (tab. 1), 146 (tab. 2), 152 (appendix); Gasca et al., 2012: 126 (tab. 1), 127‒134 (passim), 132 (tab. 3), 133 (tab. 4), 134 (tab. 5), 135 (tab. 6); Lavaniegos, 2014: 5 (tab. 1); Valencia et al., 2013: 52 (tab. 1); Violante-Huerta et al., 2021: 81 (tab. 1).

Oxycephalus erythraeus Cecchini, 1929: 482‒483 , pl. 2.

Material examined. 50M, 102F in 24 localities ( Fig. 2 ).

TALUD I. St. 6 (23°15’54”N, 107°31’12”W), December 12, 1989 , 1M, BO, from surface to 1550 m (TD> 2000 m) (ICML-EMU-12950). TALUD III. St. 3B (22°36’36”N, 106°35’54”W), August 17, 1991 , 1M, 4F, I-K from surface to 275 m (TD, 1585 m) (ICML-EMU-12951-A); St. 5 (23°22’N, 107°10’W), August 24, 1991, 1F, I-K, from surface to 365 m (TD, 698 m) (ICML-EMU-12951-B); St. 6 (23º17’54”N, 107º30’18”W), August 18, 1991, 1F, AD from surface to 996‒1148 (ICML-EMU-12951-C); St. 10B (23°43’24”N, 107°39’06”W), August 18, 1991, 3F, I-K from surface to 630 m (TD, ca. 900 m) (ICML-EMU-12951-D); St. 19 (25°12’00”N, 109°07’00”W), August 20, 1991, 2M, I-K, surface to 410 m (TD, 920 m) (ICML-EMU-12952-A); St. 19B (25°18’24”N, 109°18’36”W), August 20, 1991, 1M, 4F, I-K from surface to 600 m (TD, 1890 m) (ICML-EMU-12952-B); St. 25A1 (25°51’00”N, 109°57’00”W), August 21, 1991, 4M, 3F, I-K from surface to ca. 200 m (TD, 1280-1360 m) (ICML-EMU-12952-C); St. 25A2 (25°50’54”N, 109°56’54”W), August 21, 1991, 1M, 4F, I-K from surface to 230 m (TD, ca. 1200 m) (ICML-EMU-12952-D). TALUD IV St. 7 (22°00’22”N, 106°49’18”W), August 23, 2000 , 4M, 11F, MN from surface to 500 m (TD, 1970 m) (ECOSUR-10559); St. 15 (23°23’30”N, 107°47’48”W), August 24, 2000 , 2M, 2F, MN from surface to 1500 m (TD, 2350 m) (ICML-EMU-12953-A); St. 22 (24°17’20”N, 108°50’30”W), August 26, 2000 , 5M, 3F, MN from surface to 1325 m (TD, ca. 1800 m) (ICML-EMU-12953-B); St. 25A2 (25°50’54”N, 109°56’54”W), August 21, 2000 , 3F, I-K from surface to 230 m (TD, ND) (ICML-EMU- 12954-A); St. 36 (25°51’59”N, 110°11’00”W), August 27, 2000, 1M, 1F, MN from surface to ca. 1300 m (TD, 2100 m) (ICML-EMU-12954-B) . TALUD V. St. 5 (22°00’57”N, 106°40’00”W), December 13, 2000 , 7M, 9F, MN from surface to ca. 1400 m (TD> 1600 m) (ICML-EMU-12955-A); St. 29 (25°14’36”N, 109°24’15”W), December 17, 2000 , 2F, MN from surface to 1290 m (TD, 2040 m) (ICML-EMU-12955-B) . TALUD VI. St. 7 (22°21’39”N, 107°01’42”W), March 14, 2001 , 19M, 40F, MN from surface to 1305 m (TD, 2100 m) (ICML-EMU-12956); St. 15 (23°14’42”N, 107°30’W), March 14, 2001 , 1M, 1F, MN, surface to 1300 m (TD, 2390 m) (ICML-EMU- 12957-A); St. 22 (24°17’34”N, 108°50’25”W), March 15, 2001 , 2M, 1F, MN from surface to 1410 m (TD, 1760 m) (ICML-EMU-12957-B); St. 29 (25°16’24”N, 109°24’54”W), March 16, 2001 , 1F, MN from surface to 1440 m (TD, 2080 m) (ICML-EMU-12957-C) . TALUD XI. St. 6A (16°58’00”N, 100°57’00”W), June 7, 2007 , 1M, 1F, MN from surface to 1400 m (TD, 1960 m) (ICML-EMU-12958-A); St. 19B (17°56’00”N, 103°10’00”W), June 9, 2007 , 1M, 3F, MN from surface to 1490 m (TD, 1750 m) (ICML-EMU-12958-B) . TALUD XII. St. 4 (16°59’39”N, 100°58’07”W), March 28, 2008 , 3F, MN from surface to 1200 m (TD, 1995 m) (ICML-EMU-12959); St. 15C (17°27’51”N, 102°10’43”W), March 31, 2008 , 1M, 4F, MN from surface to 1530 m (TD, 1880 m) (ICML-EMU- 12960-A); St. 28B (18°56’00”N, 104°59’57”W), April 2, 2008 , 1M, 1F, MN from surface to 1425 m (TD, 2041 m) (ICML-EMU-12960-B) .

Distribution. Circumtropical and in the Mediterranean Sea. In the eastern Pacific from California to Costa Rica, Panama, Colombia, and Chile ( Vinogradov et al. 1996, García Madrigal 2007, Valencia & Giraldo 2009, Valencia et al., 2013, Violante-Huerta et al. 2021, this study).

Remarks. Oxycephalus clausi is easily recognized for the presence of a medial tooth on the ventral margin of pleonites 1‒3, and by the shape of the anterodistal corner of the carpus gnathopods 1 and 2 which are produced in a sharp point.

Siegel-Causey (1982) reported Oxycephalus clausi as common in the Gulf of California, where it was collected in the northern, central and southern Gulf. Our results indicated a similar pattern ( Fig. 2 ). In the Mexican portion of the California Current, it has been reported as rare by Lavaniegos & Hereu (2009) and by Lavaniegos (2014; 7.5% of the samples). It inhabits predominantly in surface waters ( Zeidler 1999).

Figures

FIGURE 2. Localities where Oxycephalus clausi and O. latirostris were collected during this survey.