Elzalia, Gerlach, 1957

Lu, Yang, Sui, Xinxin & Huang, Yong, 2022, Three new species of free-living marine nematodes from the central basin of the South China Sea, Journal of Natural History 56 (17 - 20), pp. 1091-1107 : 1097-1098

Updated key to all valid species of Elzalia including the new species (based on Jia and Huang 2019)

1. Paired spicules unequal in length, left spicule distinctly longer than right one .............. ........................................................................................... E. heterospiculata Jia and Huang, 2019

- Paired spicules almost equal in length ....................................................................................... 2

2. Tail filiform, c less than 6, gubernaculum with a single section ............................................ ......................................................................................................................... E. longicaudata sp. nov.

- Tail conico-cylindrical, c greater than 6.5 .................................................................................. 3

3. Body longer than 750 µm, complex gubernaculum with three to four sections ........... 4

- Body shorter than 700 µm, simple gubernaculum with one or two sections .......... 10

4. Spicule shorter than 80 µm (6% to 8% of the body length), with subterminal sigmoid bend and two terminal tubercules..................................................................................................... .................................................................... E. kimae Castillo-Fernandez and Lambshead, 1990

- Spicule longer than 100 µm (longer than 8% of the body length).................................. 5

5. Distal end of spicules with two comb-like ridges ......................................................................... ...................................................................................... E. bipectinella Hope and Aryuthaka, 2009

- Distal end of spicules tapered, without comb-like ridges .................................................. 6

6. Spicule with a subterminal cluster of numerous tubercles ...................................................... ....................................................................................... E. tuberculata Hope and Aryuthaka, 2009

- Spicule without subterminal tubercles ........................................................................................ 7

7. Spicule with serrated margin, gubernaculum with a series of projections ........................ ........................................................................ E. poli Castillo-Fernandez and Lambshead, 1990

- Spicules without serrated margin, gubernaculum without lateral and dorsal projections .......................................................................................................................................................... 8

8. Body longer than 1.5 mm, spicule longer than 10% of the body length ........................... ................................................................................................... E. gerlachi Zhang and Zhang, 2006

- Body less than 1.1 mm, spicule shorter than 8.5% of the body length ........................ 9

9. Gubernaculum contains four sections, with leaf-like projection E. floresi Gerlach, 1957

- Gubernaculum contains three sections, without leaf-like projection ................................... ................................................................. E. federici Castillo-Fernandez and Lambshead, 1990

10. Spicule distal end bifurcate ................................................ E. bifurcata Sun and Huang, 2017

- Spicule distal end tapered, not bifurcated .............................................................................. 11

11. Files of cervical setae present, gubernaculum with a single section .................................... ................................................................................................... E. mediterranea Vitiello, 1970 -1971

- Files of cervical setae absent, gubernaculum with two sections ............................................ ............................................................................................. E. striatitenui Zhang and Zhang, 2006