Olivancillaria teaguei Klappenbach, 1964

O, Va L E R I A T E S & Pastorino, Guido, 2011, A revision of the genus Olivancillaria (Mollusca: Olividae) from the southwestern Atlantic, Zootaxa 2889, pp. 1-34 : 24

Olivancillaria teaguei Klappenbach, 1964

Figures 8A –E

Klappenbach, 1964, 132–134: pl. 8 figs. 1–2, 4–5, 8; Thomé 1966: 167; Sicardi 1967: 57; Rios 1970: 100, pl. 31; Figueiras & Sicardi 1973: 262, pl. 14 fig. 190; Rios 1975: 110, pl. 32, fig. 466; Scarabino 1977: 190; Rios 1985: 110, pl. 38, fig. 485; 1994: 142, pl. 46, fig. 608; Brazeiro & Defeo 1996: 529; Scarabino 2004: 322; Scarabino et al. 2006: 145, fig. 1; Carranza 2007: 22; Rios 2009: 269, N° 665.

Diagnosis. Shell very small (up to 25.8 mm) oval-oblong; spire short; apex rounded; columellar callus faint, poorly defined; siphonal channel, shallow; shell whitish, columellar folds and siphonal canal brownish.

Description. Shell, small, oval-oblong, medium thickness (~0.6 mm), smooth; protoconch partially covered by columellar callus; spire short; transition to teleoconch indistinct; suture channeled; columellar callus faint, uniform reaching suture; aperture elongated 3/4 of shell length; outer lip smooth, curved; 7–12 anterior oblique folds usually brownish; externally to those folds and parallel to columellar edge, 4 or 5 pronounced folds; fasciolar band well defined with posterior groove deep all along, brownish; siphonal channel shallow ( Figures 8A –E).

Shell ultrastructure of three layers: as in O. urceus ( Figure 9 F).

Radula as in other species ( Figure 9 E).

Distribution. From Chuí (33°44’S; 53°21’W), Rio Grande do Sul state, Brazil to La Coronilla (33°53’S; 53°30’W), Rocha Department, Uruguay, usually intertidal or in the surf zone.

Type material. Holotype MNHNM 1238; 25 paratypes: MORG 8845, 3 specimens, from Chuí, Rio Grande do Sul (RS); MACN-In 27537, 2; MLP 11619, 1; MNHNM 1218, 2; 1230, 7; 1237, 3; 1241, 4; MORG 17765, 1; MZUSP 188859, 2, all from La Coronilla, Rocha, Uruguay.

Type locality. La Coronilla, Rocha Department, Uruguay.

Other material examined. Brazil. Chuí, RS: MORG 39228, 46529 (intertidal). Uruguay. Chuy, Rocha: MNHNM 2174; La Coronilla, Rocha: MNHNM 4301, MORG 15199 (intertidal), 16240 (intertidal), 32618, 47367, 49177 (intertidal), MZUSP 33087, NMR 57109, MNRJ 3390.

Remarks. The small size and creamy white color of Olivancillaria teaguei are the main differences from the other species of the genus. Castellanos (1964) reported its presence in argentine waters based on the lots 1403, 3040, 3954, 4176–1, 7227 housed at MLP Buenos Aires province. No specimen of O. teaguei from the Argentina coast was ever found at the MLP or MACN. Those lots mentioned by Castellanos are O. carcellesi and O. orbignyi , both common species from the Argentina coast.

Figures

FIGURE 8. A – C, Olivancillaria teaguei Klappenbach, 1964, holotype MNHNM 1238, from La Coronilla, Rocha department, Uruguay; D – E, Olivancillaria teaguei from Uruguay; F – H, Olivancillaria contortuplicata (Reeve, 1850) holotype NHMUK 20100471 Senegal in error. Scale bar = 1 cm.

FIGURE 9. A, radula of O. contortuplicata, frontal view, scale bar = 100 µm; B, ultrastructure of the shell, scale bar = 80 µm; C, penis, scale bar = 500 µm; D, siphon, scale bar = 2 mm; E, radula of O. teaguei, frontal view, scale bar = 50 µm; F, ultrastructure of the shell, scale bar = 200 µm.