Material. Antioquia, near Titiribi, Guaca, 1600 m (Piaget 1914, Fuhrmann leg., MHNN, syntypes); Jerico, Hno. Daniel leg. (USNM 424479, 518428); near Medellin, El Picacho, Hno. Daniel leg. (USNM 518427); near Medellin, Prado, 24.iii.1970 (UVZ 83020); Frontino, G. Wallis leg., 1875 (ZMUZ 512086, ZMUZ 512088); Boyaca, Serrania de la Quinchas, xi.2014 (FEM 155184-155190); Caldas, Marmato, T. Bland leg., ex Swift (ANSP 25753-4); Manizales, xii. 2015 (FEM 173422); Manizales, Los Yarumos, 2140 m, F.J. Borrero leg., 8.viii.2009 (USDA 144833); Marmato (NHMUK n.c); Cauca, [Santander de] Quilichao (ex Preston; RMNH n.c); slopes Nevada Huila, xi.2014 (FEM 155201); "Cauca" [no further locality], F. Bonis leg. (ANSP 91229, 91231, FMNH 78780); "Cauca" [without further specification] (ANSP 78546; FEM 173424,174001-174002); ?Cundinamarca, Bogota, Wallis leg., 1872 (ZMUZ, lectotype of Bulimus violaceus; 512085); Quindfo, Ver. La Paloma, Corr. La Virginia, Calarca, 1900 m, Borrero & T. Pearce leg., 29.vii.2012 (USDA 144868); Salento, vi.2014 (FEM 142780); Ibidem, v.2015 (FEM 163026, 193858); Ibidem, x.2016 (FEM 195858-195861); Valle del Cocora, x.2014 (FEM 155200); Risaralda, Pereira (RBINS 607767); near Marsella, Reserva Forestal Quebrada La Nona, 1600-2000 m, vi.2003 (GK); Valle del Cauca, North of El Aguila, between La Linea and El Granero, 1901 m, Borrero and Pearce leg., 20.vii.2010 (USDA 144831); El Aguila, 2100-2200 m, Borrero and Pearce leg., 8.vii.2011 (USDA 144832); Rio La Paila valley, 1300 m, H. Pittier leg. (USNM 251136a); Bugalagrande, Vereda La Morena, Galicia, Hacienda Chachafruto, 1800 m, V. Rochas leg., 23-28.ii.1999 (UVZ 99096); Palmira, vi. 2014 (FEM 142749-142759); Ibidem, v.2015 (FEM 163027-163029, 165311, 174100). ?, New Granada (FMNH 77539); Ibidem, ex C.B. Adams (MCZ 154050), Ibidem, ex Dohrn (MCZ n.c); U.S. of Colombia, Bland leg., ex Redfield ex Henderson (USNM 307622); Colombia (ANSP 362436, UF 206222, NHMUK 1907.8.29.10).
Altitudinal range. A range of 1300-2600 m can be ascertained from the few precise localities known.
Ecology. The species occurs in the Cauca Valley dry and montane forests ecoregion. The actual habitat is unknown.
Remarks. There are three places with the name "Marmato" in the Geonames gazetteer, in Antioquia, Caldas and Cauca. We follow the opinion of BREURE & ESKENS (1981) that this is Marmato in Department Caldas; it lies in the valley of the Cauca river. This is a variable species, both in shape, and in colouration. Differences in relative expansion of parts of the peristome result in some specimens appearing more laterally expanded, whereas some are more basally expanded. In addition, the intensity of purplish colouration inside the aperture, as well as the intensity of colour banding on the shell, varied widely among the material examined. We agree with PILSBRY (1898 [1897-1898]: 207) in grouping Bulimus eversus Mousson, 1873 with this species; we now consider B. eversus as a junior subjective synonym of B. confluens. Adult shells can vary substantially in size, as evidenced by a lot in MHNN (32.8-46.2 mm shell height). Piaget's taxa, both described from the same locality Guaca, fall within the range of variation observed in this species and are now also considered junior subjective synonyms. Some specimens are only tentatively referred to as this species (ANSP 362436, USNM 518428, ZMUZ 512086).