Nata aequiplicata, David G. Herbert & Adnan Mousalli, 2016

David G. Herbert & Adnan Mousalli, 2016, Revision of the dwarf cannibal snails (Nata s. l.) of southern Africa — Nata s. s. and Natella (Mollusca: Gastropoda: Rhytididae), with description of three new species, Zootaxa 4094 (1), pp. 1-67 : 18

Key to species of Nata

1. Shell small with distinct, evenly and quite widely spaced, axial pliculae that extend around periphery and into umbilicus; restricted to the area just west of Port Elizabeth......................................... Nata aequiplicata sp. nov.

- Shell small to moderate in size, sculpture weak (essentially growth-lines only), or with close-set axial riblets that evanesce at periphery, the base with weak growth-lines only.............................................................. 2

2. Shell lacking distinct and regular axial riblets, sculpture largely consisting only of relatively fine, irregularly spaced growthlines................................................................................................ 3

- Strength of shell sculpture variable, but adapical surface (or at least the subsutural part thereof) always with some evidence of close-set axial riblets................................................................................... 4

3. Radula with ≥19 teeth per half-row, lacking a distinct fang tooth; largely confined to the Albany Thicket Biome.............................................................................................. Nata watsoni sp. nov.

- Radula with ≤12 teeth per half-row, one of which (the fang tooth) is clearly larger than the others; inland and montane regions of eastern South Africa and Lesotho (mostly above 1000 m), as well as at lower altitudes in Maputaland and the Lowveld of Mpumalanga........................................................................ Nata erugata sp. nov.

4. Adult diameter> 20 mm; widespread throughout southern and eastern South Africa...................... Nata vernicosa

- Adult diameter <15 mm; W. Cape only.................................................................... 5

5. Shell with relatively strong, crisp, evenly spaced and close-set axial riblets on the adapical surface, often lustreless; adult shell with rather globose profile and compact whorls; Cape Peninsula and Atlantic Cape coast................. Nata dumeticola

- Shell with less regular axial riblets, usually glossy; profile somewhat depressed and whorls comparatively rapidly expanding; more widely distributed in south-western Cape................................................. Nata tarachodes