Cactodera tianzhuensis, Li & Li & Ni & Shi & Wei & Liu & Zhang & Peng, 2021

Li, Wenhao, Li, Huixia, Ni, Chunhui, Shi, Mingming, Wei, Xuejuan, Liu, Yonggang, Zhang, Yiwen & Peng, Deliang, 2021, A new cyst-forming nematode, Cactodera tianzhuensis n. sp. (Nematoda: Heteroderinae) from Polygonum viviparum in China with a key to the Genus Cactodera, Journal of Nematology 53 (1), pp. 1-15 : 12-14

Key to species of CaCTODera

(Modified from Cid Del Prado and Subbotin, 2014; Feng et al., 2018; Subbotin et al., 2010)

1. Cyst generally two times or more longer than wide, mean L/W ratio=2.3...........… C. eStOniCa - Cyst usually less than twice as long as wide, mean L/W ratio =1.1–1.8…....................…….2

2. Eggshell punctate…........................................3

- Eggshell smooth…........................................11

3. Mean stylet length of J2s ≥ 26μm…......……. 4

- Mean stylet length of J2s <26μm…….….......5

4. J2s tail length=48–64μm, hyaline region=23– 28μm, fenestral diam.=23–41μm…… C. thOrnei

- J2s tail length=37–48μm, hyaline region=17– 24μm, fenestral diam.=14–25μm..… C. eremiCa

5. Mean J2s body length ≥411 μm…..………….6

- Mean J2s body length <411μm…..…………...9

6. Mean J2s tail length> 40μm, mean cyst length>440 μm, mean cyst width>325 μm….………7

- Mean J2s tail length ≤40μm, mean cyst length ≤440μm, mean cyst width ≤ 325μm….. C. SOlani

7. b ratio <3.5, fenestral diam.<20μm........ C. milleri

- b ratio>3.5, fenestral diam.>20μm…..………8

8. Female L/W ratio <1.4, mean hyaline region of J2s <22μm…................................…… C. CaCti

- Female L/W ratio ≥1.4, mean hyaline region of J2s ≥ 22μm……...................… C. ChenOpOdiae

9. Fenestral diam. <25μm…..…………………. 10

- Fenestral diam. ≥ 25μm……….… C. galinSOgae

10. Hyaline region of J2s =4–8μm…......… C. rOSae

- Hyaline region of J2s =16–23μm….… C. eVanSi

11. Mean J2s tail length <40μm………………....11

- Mean J2s tail length ≥ 40μm……………........14

12. Mean J2s body length <406 μm, mean hyaline region <16μm…..………………… C. amaranthi

- Mean J2s body length ≥406μm, mean hyaline region ≥16μm…………................................13

13. Cyst with distinct vulval cone, J2s stylet length =21.0–23.0μm…..........…. C. tOrreyanae

- Cyst without distinct vulval cone, J2s stylet length =23.4–25.0 μm…...................… C. Salina

14. J2s stylet knobs anterior surface concave, DGO= 4.5–5.6μm…………….......................15

- J2s stylet knobs anterior surface convex, DGO= 2.5–3.0μm……………......... C. aCnidae

15. Vulval denticles present……………………….16

- Vulval denticles absent.……………. C. radiCale

16. Mean J2s body length <489 μm, J2s stylet length =20–22 μm……..............….…. C. WeiSSi

- Mean J2s body length ≥ 489μm, J2s stylet length =23–26 μ m…….… C. tianZhUenSiS n. sp.