A revision of the genus Olivancillaria (Mollusca: Olividae) from the southwestern Atlantic Author O, Va L E R I A T E S Author Pastorino, Guido text Zootaxa 2011 2889 1 34 journal article 46845 10.5281/zenodo.207201 104bba85-f85f-4edb-bc76-3467cc30aff5 1175-5326 207201 Olivancillaria contortuplicata ( Reeve, 1850 ) Figures 8 F–H; 9 A–D Oliva contortuplicata Reeve, 1850 : pl. 20, fig. 51; Marrat 1871 : 27 , pl. 20, figs. 332–333. Agaronia contortuplicata . Adams & Adams 1853: 142; Gray 1858 : 52 . Oliva (Olivancillaria) auricularia . Tryon 1883 : 90 –91, pl. 36, fig. 94 ( non Lamarck, 1811 ). Olivancillaria contortuplicata . Barattini & Ureta 1961 : 128 , pl. 37; Burch & Burch 1964 : pl. 7, fig. 7; Thomé 1966 : 167 ; Sicardi 1967 : 57 ; Rios 1970 : 100 , pl. 30; Figueiras & Sicardi 1973 : 261 , pl. 14 fig. 188; Rios 1975 : 110 , pl. 32, fig. 463; Rios 1985 : 109 , pl. 37, fig. 483; Abbott & Dance 1986 : 193 ; Calvo 1987 : 162 , fig. 143; Tursch 1988 : 246 ; Rios 1994 : 142 , pl. 45, fig. 606; Scarabino 2004 : 322 ; Scarabino et al . 2006: 145, fig. 1; Carranza 2007: 22; Rios 2009 : 268 , N° 663. Diagnosis. Shell small (up to 35.1 mm in length); spire high, apex never covered by callus; columella with a conspicuous groove, posterior to columellar folds; shell grayish, fasciolar band whitish, with light brown areas. Description. Shell small oval-oblong; the thinnest of the species discussed (~0.4 mm), smooth; protoconch of 1 1/2 translucent whorls, transition to teleoconch indistinct; spire high, of 4 convex whorls, suture channeled; columellar callus faint, extended just towards suture; aperture elongated, about 3/4 of total shell length; outer lip smooth slightly curved; posterior part of columella slightly convex, smooth with a marked, groove posterior to the anterior columellar folds; 4–5 anterior oblique folds, 2–3 conspicuous folds parallel to columellar edge; fasciolar band distinctive; shell whitish with light brown areas; posterior groove deep; siphonal channel deep ( Figures 8 F– H). Shell ultrastructure of three layers: as in O . urceus ; ( Figure 9 B). Radula ( Figure 9A ) as in O . auricularia . The penis is similar to the other species of the genus, with the tip slightly pointed ( Figure 9 C) as in O . urceus . Siphon large with numerous branched papillae in the distal tip ( Figure 9 D) as in O . urceus . Distribution. Imbituba ( 28°07’S ; 48°41’W ), Santa Catarina state, Brazil to La Paloma ( 34°39’S ; 54°09’W ), Rocha department, Uruguay , usually intertidal. Type material. Holotype NHMUK 20100471 ( Figures 8 F–H). Type locality. It was originally cited from the coast of Senegal , Africa. There were no other reports from this locality after the original description. It is probably mistaken. Barattini & Ureta (1961) and subsequent authors cited this species from the coast of Uruguay and Brazil . Other material examined. Brazil . Imbituba, Santa Catarina (SC): MORG 25083 (intertidal); Laguna, SC: MORG 47896; Tramandaí, Rio Grande do Sul (RS): MZUSP 51084, MNRJ 843, 2881; São José do Norte, RS: MNRJ 774; Rio Grande, RS: MZUSP 51268, MNRJ 3595; Cassino, RS: MORG 30, 11892 (intertidal), 39156; Chuí, RS: MNHNM 9094, MNRJ 8538, MORG 88535, 886, 9292, 10576, MZUSP 33088; RS: MORG 3188, 3318 (intertidal), 4543 (intertidal), 7343, 8006, 9137, 9401, 9857, 15667, 17739, 31379 (intertidal), MZUSP 10648, 16200. Uruguay . Chuy, Rocha: MNHNM 3160; La Coronilla, Rocha: MLP 4334-2, 9584, MNHNM 279, 3159, 9088, 9090, 9091, 9092, 9096, 9097, 9098, 9552, MNRJ 1217, 6451, 6531, MORG 16243, 19070, 32615, 47368 (intertidal), 49178 (intertidal), 50305, NMR 62170; La Paloma, Rocha: MNHNM 9095, MNRJ 841, MORG 9503, MZUSP 52030, Punta del Este, Maldonado: MNHNM 2081, MORG 11198. Remarks. O . contortuplicata was well understood since its description, perhaps because the shell is unique and has little variation. As far as we know, there are no synonymous names and the species is restricted to southern Brazil and Uruguay .