Pelagic amphipods (Crustacea: Amphipoda: Hyperiidea) in western Mexico. 6. Superfamily Vibilioidea. Families Paraphronimidae and Vibiliidae Author Gasca, Rebeca 0000-0002-9716-1964 El Colegio de la Frontera Sur, Unidad Chetumal, Av. del Centenario km 5.5, Chetumal, Quintana Roo, 77014, Mexico. rgasca @ ecosur. mx; https: // orcid. org / 0000 - 0002 - 9716 - 1964 rgasca@ecosur.mx Author Hendrickx, Michel E. Laboratorio de Invertebrados Bentónicos, Unidad Académica Mazatlán, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, PO Box 811, Mazatlán, 82000 Sinaloa, Mexico. text Zootaxa 2021 2021-11-25 5071 4 563 578 journal article 3300 10.11646/zootaxa.5071.4.5 084d8de1-dab3-4d6e-9db0-69e853c39709 1175-5326 5726520 B81C6E57-229D-4AA4-BA87-8EF6BD135F2B Paraphronima crassipes Claus, 1879 Paraphronima crassipes Claus, 1879: 7 (65), 8 (66), pl. 1, figs. 6‒9, pl. 2, fig. 10; Siegel-Causey, 1982: 139 (key), 140; Vino- gradov et al ., 1996: 316‒318, fig. 127; Zeidler, 2003: 89 (key), 91‒94, figs. 37B, 38; Brusca & Hendrickx 2005: 149 (list); García Madrigal, 2007: 143 (list); Guillén Pozo, 2007: 20 (key), 36, fig. 8, 121 (tab. 1), 138‒178 (passim), 149 (tab. 40); Lavaniegos & Hereu, 2009: 142 (tab. 1), 151 (appendix 1); Valencia & Giraldo, 2009: 268 (tab. 1); 2012: 1492 (tab. 1); Valencia et al . 2013: 51 (tab. 1); Lavaniegos, 2014: 4 (tab. 1). Hyperia pedestris Guérin-Méneville, 1836 : pl. 25, fig. 6; Zeidler, 1995: 310‒311 (passim). Paraphronima clypeata Bovallius, 1885: 11 , fig. 2. Paraphronima pectinata Bovallius, 1887: 13‒14 . Paraphronima cuivis Stebbing, 1888: 1337‒1342 , pl. 157. Material examined . 18M and 11F from 9 localities ( Fig. 1 ). TALUD III . St. 19B ( 25°18’24”N , 109°18’36”W ), August 20, 1991 , 2M, IK from surface to 600 m ( TD , 1890 m ) (ICML-EMU-12829). TALUD IV . St. 7 ( 22°00’22”N , 106°49’18”W ), August 23, 2000 , 3M, 1F, MN from surface to 500 m ( TD , 1970 m ) (ICML-EMU-12830-A); St. 22 ( 24°17’20”N , 108°50’30”W ), August 26, 2000 , 4M, 1F, MN from surface to 1325 m ( TD , approx. 1800 m ) (ICML- EMU-12830-B); St. 36 ( 25°51’59”N , 110°11’00”W ), August 27, 2000 , 3M, 3F, MN from surface to approx. 1300 m ( TD , 2100 m ) (ICML-EMU-12830-C). TALUD V . St. 5 ( 22°00’57”N , 106°40’00”W ), December 13, 2000 , 5M, 2F, MN from surface to ca 1400 m ( TD > 1600 m ) ( ECO-CH-Z 10547 ); St. 36 ( 25°54’30”N , 110°11’24”W ), December 17, 2000 , 1M, MN from surface to 1340 m ( TD , 1990 m ) (ICML-EMU-12831). TALUD VI . St. 7 ( 22°21’39”N , 107°01’42”W ), March 14, 2001 , 2F, MN from surface to 1305 m ( TD , 2100 m ) (ICML-EMU-12832-A); 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-12832- B); St. 36 ( 25°53’15”N , 110°10’06”W ), March 17, 2001 , 1F, MN from surface to 1360 m ( TD , 2000 m ) (ICML- EMU-12832-C) . Distribution . Cosmopolitan in tropical and subtropical waters including the Mediterranean Sea. In the Atlantic and Pacific oceans occurring up to 42°N and 52°N , respectively; rarely found in the Antarctic convergence ( Vinogradov et al . 1996 ). In the eastern Pacific it ranges from Newport, California , USA , to the Gulf of California , Mexico (García Madrigal 2007). Remarks . Collected in 0‒1600 m , but rare below 500 m ( Vinogradov et al . 1996 ). This species and its congener, P. gracilis Claus, 1879 , are very difficult to identify because the characteristics used to differentiate them are sometimes mixed-up. These characters include the amplitude of the angle between the pereion and the first epimeral plate, the presence of spines on the ventral margin of pereopods 5‒7, and the relative length of pereopod 7. Both species are frequently found in the same sample.