Description of Xiphinema hangzhouense sp. n. (Nematoda: Longidoridae) from the rhizosphere of Magnolia grandiflora in Hangzhou, Zhejiang Province, China

Abstract

Xiphinema hangzhouensesp. n. is described from the rhizosphere ofMagnolia grandiflorain Hangzhou, China. The new species is characterised by having a monodelphic reproductive system, slim body, total stylet = 186-192μm long and vulva located anteriorly at 27.6-31.2% of total body length. The new species has a gonad 400-450μm long with a simple uterus and no Z-organ. The female tail is elongated conoid with a rounded terminus. The species has four juvenile stages and no male was found. The polytomous identification codes ofX. hangzhouensesp. n. are A1, B4, C2, D23, E12, F2, G2, H2, I23, J2, K2, L1. The new species is morphologically similar toX. winotoi. Phylogenetic analyses of the 28S rRNA, ITS rRNA, 18S rRNA and partialCOIgene sequences ofX. hangzhouensesp. n. and some closely relatedXiphinemaspecies revealed that the new taxon clustered with high statistical support withX. radicicolaandX. setariae.

Description of Xiphinema parachambersi sp. n. (Nematoda: Longidoridae) from Imported Ornamental Plants in Japan with a Key to Xiphinema Species in Group 1

“…Our phylogenetic studies suggested that species in the morphospecies group 1 are not monophyletic, and morphospecies grouping was only established for the convenience of identification and do not always reflect the evolutionary history, which is consistent with other studies (Handoo et al, 2016;Cai et al, 2018). Considering the high variability in the morphological characters in Xiphinema species, it is necessary to use integrated morphological and molecular approaches in species diagnosis, especially in making a regulatory decision regarding the movement of soil and plant material.…”

“…This morphospecies group comprises species with anterior genital branch completely absent to a very small post uterine sac. Among 12 species in this group, i.e., X. brasiliense, X. chambersi, X. ensiculiferum, X. fagesi, X. hunaniense, X. hangzhouense, X. monasiae, X. monohysterum, X. naturale, X. orthotenum, X. radicicola and X. winotoi (Loof and Luc, 1993;Loof et al, 1996;Cai et al, 2018), only a few species were described with molecular characterizations. This study added another species with complete morphological and molecular characterization, which will help to enhance the knowledge and understanding to the classification of this group of nematodes.…”

“…Morphospecies group 1 represents species having single gonad (monodelphic), all the known species in this group are small and have an anteriorly located vulva, simple or undifferentiated posterior uterus, lacking Z organ (Cohn and Sher, 1972). With the most recent described X. hanzhouense (Cai et al, 2018), there are 12 nominal species in this group. The important characters to distinguish these species are the shape and lengths of tail and its hyaline region.…”

“…Primers for amplification of 18S were forward primer K4f and reverse primer K1r (Penas et al, 2006). Primers for amplification of ITS1 were forward primer V1 (Ferris et al, 1993) and reverse primer 5.8S (Cherry et al, 1997). Primers for amplification of 28S D2/D3 were forward primer D2A and reverse primer D3B (De Ley et al, 1999).…”