Key to species of Phialodonta gen. nov.

1 Spire flat or slightly sunken ............................................................................................................... 2

– Spire elevated above level of last adult whorl ................................................................................... 3

2 Palatal region with 1–3 axially aligned pairs of rounded denticles situated approx. 0.25 whorl apart; KwaZulu-Natal ....................................................................... P. introtuberculata gen. et comb. nov.

– Palatal region with three in-running ridge-like denticles; W. Cape ........ P. agulhasae gen. et sp. nov.

3 Adult shell with no parietal dentition visible through aperture ......................................................... 4

– Adult shell with parietal dentition visible through aperture .............................................................. 5

4 Palatal region with two long, in-running lamellae (visible only by transparency) .............................. ................................................................................................................. P. perfida gen. et comb. nov.

– Palatal region with three in-running lamellae (visible only by transparency) ..................................... ...................................................................................................................... P. aviana gen. et sp. nov.

5 Palatal region with 3–4 recessed denticles, plus a narrow, in-running baso-columellar ridge .......................................................................................................... P. rivalalea gen. et sp. nov.

– Palatal region with two pairs of close-set, spirally aligned denticles, no dentition in baso-columellar region ................................................................................................. P. atromontana gen. et sp. nov.