Trefusiina, Siddiqi, 1983

Leduc, Daniel, Zhao, Zeng Qi & Sinniger, Frederic, 2020, Halanonchus scintillatulus sp. nov. from New Zealand and a review of the suborder Trefusiina (Nematoda: Enoplida), European Journal of Taxonomy 661 (661), pp. 1-45 : 32

Key to the genera of suborder Trefusiina ( Simpliconema not included due to lack of data on females, but see Fig. 9 for pictorial key of all genera)

1. Female reproductive system monodelphic ....................................................................................... 2 – Female reproductive system didelphic ........................................................................................... 10

2. Female reproductive system monodelphic with anterior ovary ........................................................ 3 – Female reproductive system monodelphic with posterior ovary ...................................................... 8

3. Cephalic capsule present ................................................................................... Xennella Cobb, 1920 – Cephalic capsule absent .................................................................................................................... 4

4. Buccal cavity with teeth .................................................................................................................... 5 – Buccal cavity without teeth .............................................................................................................. 6

5. Cephalic setae and outer labial setae in single circle .................................... Tripylina Brzeski, 1963 – Cephalic setae and outer labial setae in separate circles ............................ Trischistoma Cobb, 1913

6. Female gonad and intestine both ending in cloaca ........................................................................... 7 – Vulva located very close to anus .......................................... Lauratonematoides De Coninck, 1965

7. Asymmetric male copulatory apparatus, gubernacular apophyses present ........................................ ....................................................................................................... Lauratonemella Tchesunov, 1984

– Symmetric male copulatory apparatus, gubernacular apophyses absent ............................................ ............................................................................................................... Lauratonema Gerlach, 1953

8. Buccal cavity small, funnel-shaped ........................................................... Rhabdocoma Cobb, 1920 – Buccal cavity large, with cuticularized walls ................................................................................... 9

9. Buccal cavity uncompartmentalized, amphid elongate ...... Africanema Vincx & Furstenberg, 1988 – Buccal cavity with discontinuity between gymnostoma and stegostoma, amphid pocket-shaped with oval or circular opening ............................................................................ Halanonchus Cobb, 1920

10. Pairs of discoid supplements present in pre- and post-cloacal regions of male ................................. .................................................................................................................... Cytolaimium Cobb, 1920 – Discoid supplements absent .............................................................................................................11

11. Cephalic setae and outer labial setae in single circle ........................ Trefusialaimus Riemann, 1974 – Cephalic setae and outer labial setae in separate circles ................................................................. 12

12. Female reproductive system with two posterior ovaries, outer labial setae not jointed, secretoryexcretory pore on setiform elevation .............................................................. Porocoma Cobb, 1920

– Female reproductive system with two opposed and reflexed ovaries, jointed outer labial setae, secretory-excretory pore not on setiform elevation ....................................... Trefusia De Man, 1893

Figures

Fig. 9. Anterior and posterior body regions of Trefusiina genera (members of the families Simpliconematidae, Xennellidae, Trischistomatidae and Lauratonematidae) (continued on next page). A. Simpliconema aenigmatoides Blome & Schrage, 1985. B. Xennella suecica Allgén, 1935. C. Porocoma striata Cobb, 1920. D. Tripylina arenicola (de Man, 1880) Brzeski, 1963. E. Trischistoma gracile Andrássy, 1985. F. Lauratonema juncta Fadeeva, 1989. G. Lauratonemella spiculifer (Gerlach, 1959) Tchesunov, 1984. H. Lauratonemoides minutus (Platonova, 1971) Tchesunov, 1984. Drawings modified from De Coninck (1937), Gerlach (1959, 1962), Blome & Schrage (1985), Fadeeva (1989) and Andrassy (2007).