1.	Clitellum annular evenly developed also on the ventral side	2
	Clitellum saddle shaped, ventrally always less developed	3
2.	Male pore postsetal, clitellum on 23-28	B. palustris Moore, 1895
	Male pore setal on a huge porophore, clitellum ends on 30	B. schwerti sp. nov.
3.	Clitellum ends on or after segment 34	4
	Clitellum ends on or before segment 33	6
4.	Clitellum on 24, 25-34, 35	5
	Clitellum on 27-37	B. zeteki (Smith & Gittins, 1915)
5.	Septa 8/9-11/12 thickened, setal ratio ab:cd = 1.5:1	B. welchi (Smith, 1917)
	Septa 12/13-14/15 thickened, setal ratio ab:cd = 1:1	B. lawrenceae Fender, 1994
6.	Clitellum ends before segment 31	7
	Clitellum ends on or after 31	9
7.	Septa 7/8-9/10 thickened, typhlosole bifid	B. gieseleri (Ude, 1895)
	All septa membranous, Typhlosole lamellar	8
8.	Clitellum on 24 (25) -30, color dark brown-red	B. parvus (Eisen, 1874)
	Clitellum on ½21, 22-29, ½30, color light red-violet	B. tumidus (Eisen, 1874)
9.	Septa strongly 7/8-11/12 thickened, clitellum on 22, 23-32, 33	B. longicinctus (Smith & Gittins, 1915)
	All septa membranous or just slightly thickened	10
10.	Prostomium tanylobic	B. eiseni (Levinsen, 1884)
	Prostomium epilobic	11
11.	Clitellum on ½24, 25-32, ½33	B. heimburgeri (Smith, 1928)
	Clitellum on 26-31, ½23	B. rubidus (Savigny, 1826)