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 : 10-11

C. Salina 415–742 193–475 1.4–2.2 Absent

30 × 33 361–448 2.5–3.0 19–25 43–48 17–26

25–38 340–460 3.9–5.1 20–21 32–40 12–16

16–30 456–540 2.9–4.4 24–26 49–60 14–21

20–26 438–539 3.1–4.3 22–26 39–51 17–28

14–25 440–510 3.5–6.0 25–28 36–47 17–23

18–30 426–465 3.4–4.3 22–24 36–44 14–21

18–23 358–420 2.8–4.0 20–24 34–44 16–23

33–56 358–443 – 19–31 26–45 10–24 14–18 370–479 3.2–5.1 21–23 37–49 15–21

17–28 467–520 3.6–5.8 20–27 46–60 15–28

10–21 348–472 – 16–26 31–68 4–8

20–28 410–514 2.5–4.0 23–25 31–48 10–31 Smooth

Smooth

Punctate

Punctate

Punctate

Smooth

Punctate

Punctate Punctate

Smooth

Punctate

Smooth

Schuster and Brezina (1979)

Golden and Raski (1977)

Graney and Bird (1990)

Feng et al. (2018)

Baldwin and Bell (1985)

Golden and Raski (1977)

Cid Del Prado and Rowe (2000)

Soto et al. (2003)

Graney and Bird (1990)

Subbotin et al. (2010)

Cid Del Prado and Miranda (2008)

Baldwin et al. (1997)

Raski and 2014) Escobar-Avila 2020 al.) (et and Golden) (1977 In study this Del Cid Prado Subbotin (and Golden 1977 () Raski

Punctate Punctate Smooth Smooth Smooth

23 28 29 25 24

– – – – –

12 23 22 16 17

49 64 59 45 50

– – – – –

28 49 47 32 43

27 28 26 23 22

– – – – –

24 25 23 21 20

6.9 7 6.5 4 5.6

– – – – –

3.7 5 4.0 2 4.5

511 620 592 550 489 – – – – – 379 446 495 390 407). 36 36 32 26 38 Range – – – × – (20 31 20 20 29 standard Present Present Present Absent Present mean ±

: 1.4 1.9 1.6 2.9 2.3 form – – – – – 1.2 1.2 1.1 1.4 1.2 the in 505 – 581 – 558 – 432 – 394, and – 204 286 361 92 350 m μ

in 581 806 761 712 598 are – – – – – SOlani 291 485 thOrnei TIaNZHueNSIS 511. sp tOrreyanae 364 524 WeiSSi All measurements: C.. C. C n.. C C. Note the lower and upper morphometric data of the ranges may overlap with other related species, CaCtOdera spp. will be identified more accurately based on morphological, morphometric, and molecular data.

In our molecular phylogenetic studies, C. tianZhUenSiS n. sp. formed a single clade with CaCtOdera species and showed closely related to C. eStOniCa and CaCtOdera sp. (original identified in GenBank as C. eStOniCa ; unpublished). However, sequence divergence (ranged from 6 to 8bp for 28 S; 30 to 38bp for ITS) and morphological characteristics can easily distinguish these species. Presently, out of seventeen valid species, six CaCtOdera species are not represented in GenBank database (i.e., C. aCnidae ( Schuster and Brezina, 1979) Wouts, 1985 , C. amaranthi (Stoyanov, 1979) Krall and Krall, 1978 , C. eremiCa Baldwin and Bell, 1985 , C. eVanSi Cid Del Prado and Rowe, 2000 , C. radiCale Chizhov, Udalova and Nasonova, 2008 , C. thOrnei ( Golden and Raski, 1977) Mulvey and Golden, 1983 ). Thus, sequences information with the genus CaCtOdera is still limited in molecular data and need to be completed in more studies.

C. tianZhUenSiS n. sp. is isolated from POlygOnUm ViViparUm L. in Tianzhu county, this habitat located in continental highland with the vegetation type of meadow grassland and the soil is composed of chernozems. The previous studies reported only three species of cyst-forming nematodes (two HeterOdera species and one GlObOdera species) from this habitat. Li et al., 2020 described a new HeterOdera species found in the rhizosphere of MiCrOUla SikkimenSiS and named HeterOdera miCrOUlae (Li, et al., 2020) and several scholars reported HeterOdera aVenae Wollenweber, 1924 associated with meadow grass ( KObreSia myOSCUrOideS, KObreSia hUmiliS and AChnatherUm inebrainS) ( Li et al., 2015; Zhang et al., 2019) and GlObOdera artemiSiae parasitizing on Chinese herbal medicine ( ArtemiSia argyi ) ( Han et al., 2020). To our best knowledge, there is no report of the genus CaCtOdera damage plants in this habitat and this is first species described of CaCtOdera species in this habitat, the fourth CaCtOdera species in China. Though few studies on the host-suitability of several species of CaCtOdera spp. have been evaluated, barley ( HOrdeUm VUlgare L.) is known as being a host for C. galinSOgae and C. rOSae ( Cid Del Prado and Miranda, 2008) , and recently described C. SOlani on tomato ( SOlanUm lyCOperSiCUm ) was reported ( Escobar-Avila et al., 2020). In addition, Graney and Bird (1990) performed a host range test of C. milleri including 34 plant species and indicated this species can reproduce on quinoa ( ChenOpOdiUm QUinOa ). Moreover, three species of CaCtOdera (namely, C. ChenOpOdiae , C. tOrreyanae , C. SOlani ) were shown to be endoparasitic to semi-endoparasitic in sessile habit, a characteristic that the juveniles penetrate with anterior body into the host roots and the posterior body protruding from the surface of the roots ( Cid Del Prado and Subbotin, 2014; Escobar-Avila et al., 2020; Feng et al., 2018). Therefore, the biology, host-suitability, and distribution of CaCtOdera species (including C. tianZhUenSiS n. sp.) should further studies to explore.