Identification key to the genus Euthyonidiella

1. Table ossicles with spire formed with four pillars............................................................ 2

- Table ossicles with spire formed with two pillars….......................................................... 6

2. Table ossicles with square or rectangular shaped disc….............................................. E. arenicola

- Table ossicles with circular shaped disc….................................................................. 3

3. Support modified table ossicles which consist of a spire absent in tube feet.......................… E. zulfigaris sp. nov.

- Support modified table ossicles which consist of a spire present in tube feet…..................................... 4

4. Spire of support modified table ossicles in tube feet with support bars forming a net-like appearance....... E. tungshanensis

- Spire of support modified table ossicles in tube feet tack-like without support bars…................................ 5

5. Rosette ossicles present in tentacles…............................................................... E. dubia

- Rosette ossicles absent in tentacles…............................................................. E. aculeata

6. Support modified table ossicles present in tube feet…........................................................ 7

- Support modified table ossicles absent in tube feet…......................................................... 9

7. Spire of support modified table ossicles in tube feet not tack-like….............................................. 8

- Spire of support modified table ossicles in tube feet tack-like…......................................... E. ambigua

8. Support modified table ossicles in tube feet with spire ending with few short spines….................... E. kyushuensis

- Support modified table ossicles in tube feet with spire ending in two diverging spines…....................... E. zacae

9. Rod ossicles absent in tentacles; thick elongate perforated plate present in tentacles….......................... E. huwi

- Rod ossicles present in tentacles; thick elongate perforated plate absent in tentacles.............................. …10

10. Rosette ossicles absent in tentacles…........................................................... E. destichada

- Rosette ossicles present in tentacles….................................................................... 11

11. Support rods present in tube feet…............................................................ E. occidentalis

- Support rods absent in tube feet…................................................................... E. trita