Species of Scina Prestandrea, 1833 (Amphipoda, Hyperiidea, Scinidae) from western Mexico with the description of a new species from the Gulf of California Author Gasca, Rebeca El Colegio de la Frontera Sur, Chetumal, Av. del Centenario Km. 5.5, Chetumal, Quintana Roo, 77014, Mexico. 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 2020 2020-06-26 4803 2 329 344 journal article 10.11646/zootaxa.4803.2.5 1175-5326 3909163 F91C0D6F-E2A1-4363-B39A-828D1F9C8D14 Scina nana Wagler, 1926 Scina nana Wagler, 1926: 393 , fig. 37; Siegel-Causey, 1992: 87; Vinogradov et al., 1996: 205 , fig. 83; Brusca & Hendrickx, 2005: 148 (list); García-Madrigal, 2007: 137 (list); Zeidler & de Broyer, 2009: 19 (list) (complete synonymy). Material examined . TALUD III , St. 19 ( 25°12’00”N , 109°07’00”W ), August 20, 1991 , 1M, IK from surface to 410 m ( TD , 920 m ) (ICML-EMU-12462A) . TALUD V , St. 5 ( 22°00’57”N , 106°40’00”W ), December 13, 2000 , 1F, MN from surface to ca. 1400 m ( TD > 1600 m ) (ICML-EMU-12462B) . Eastern Pacific distribution . Gulf of California, from off Lobos Island to off San José del Cabo, Mexico ( Brusca & Hendrickx 2005 ; García-Madrigal 2007 ). Records in this study are from the same area but along the East coast of the Gulf of California ( Fig. 4 ). FIGURE 4 . Localities where Scina nana Wagler, 1926 , Scina pacifica ( Bovallius, 1887 ) , S. setigera Wagler, 1926 , and S. submarginata Tattersall, 1906 , were captured during this survey. Remarks . The specimens found include an adult male and a female, with a total length of 3.8 and 4 mm , respectively; they are almost twice as long as those recorded by Zeidler (1990) , but within the species size range ( 2‒4 mm in mature individuals) as reported in the original description by Wagler (1926) . This species resembles S. similis (Stebbing, 1888) and, as noticed by Zeidler (1990) , there is an overlap between the characteristics of these two species. He observed that the main differences to distinguish these species (differences that were observed in the specimens analyzed here) are the short dactylus on pereopods 5‒7 and the presence of an anterodistal spine on the basis of pereopod 5. Although the exopods appear to be shorter (i.e., 6% of uropod 1 length) of what is usually found in this species (15%), these structures could be broken off.