Bylgides, Chamberlin, 1919

Key to all species of Bylgides View in CoL

1. Nuchal lobe present................................................................................... 2 Nuchal lobe absent................................................................................... 4

2(1). Presence of spots around the eyes, smooth notochaetae throughout.................... Bylgides samueli sp. nov. ( Brazil) Absence of spots around the eyes, spiny notochaetae throughout................................................ 3

3(2). Nodular dorsal tubercle............................................. Bylgides acutisetis Loshamn, 1981 View in CoL ( Norway) Bulbous dorsal tubercle with a flattened digitiform process projecting laterally.................................................................................................... Bylgides annenkovae Pettibone, 1993 View in CoL ( Norway)

4(1). Elytra with microtubercles............................................................................. 5 Elytra without microtubercles........................................................................... 6

5(4). Neurochaetae with smooth capillary tips and some slightly hook-shaped tips, cylindrical elytral papillae with clavate tips and rounded chitinous bases.............................. Bylgides sarsi View in CoL (variety) (Kinberg in Malmgren, 1866) ( Sweden) Neurochaetae with plumose and slender tips, clavate elytral papillae......... Bylgides macrolepidus ( Moore, 1905) View in CoL ( Russia)

6(4). Presence of spots around the eyes; elytra smooth................................. Bylgides cinthyae sp. nov. ( Brazil) Absence of spots around the eyes; elytra papillated........................................................... 7

7(6). Filiform elytral papillae....................................... Bylgides fuscus ( Hartman & Fauchald, 1971) View in CoL ( USA) Elytral papillae otherwise............................................................................... 8

8(7). Indistinct nephridial papillae.......................................... Bylgides belfastensis Pettibone, 1993 View in CoL ( USA) Distinct nephridial papillae............................................................................. 9

9(8). All neurochaetae with long capillary tips.................................................................. 10 Neurochaetae with capillary tips and some with slightly hook-shaped tips........................................ 11

10(9). Elytral papillae with circular base, tapering distally.................... Bylgides promamme ( Malmgren, 1867) View in CoL ( Russia) Elytral papillae with cylindrical base, not tapering distally............. Bylgides groenlandicus ( Malmgren, 1867) View in CoL ( Russia)

11(9). Cylindrical elytral papilla with clavate tip and absent chitinous bases............. Bylgides elegans ( Théel, 1879) View in CoL ( Russia) Cylindrical elytral papilla without clavate tip and present chitinous bases.................................................................................................. Bylgides sarsi View in CoL (Kinberg in Malmgren, 1866) ( Sweden)