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Summary Cryphodera japonicum n. sp., detected at Ningbo port, China, from the rhizosphere of imported Japanese Podocarpus macrophyllus, is described. The new species is characterised by females with a globose body, protruding vulval lips, slightly concave anus-vulva profile, a stylet length of 37.2 (31.1-41.3) μm and a vulva-anus distance of 38.1 (34.7-44.1) μm. Males possess two lip annuli, a stylet length of 27 (22.5-30.6) μm long, three lines in lateral fields and a spicule 21.5 (19.1-23.0) μm long. Second-stage juveniles have bodies 543 (506-588) μm long, three lip annuli, a stylet 31.7 (29.2-34.5) μm long, three lines in the lateral fields, a conoid tail with a narrow rounded terminus, and a relatively long hyaline region occupying half of the tail length. Phylogenetic analyses based on the D2-D3 expansion segments of the 28S, ITS, partial 18S rRNA, and COI gene revealed the unique position of this species with other heteroderid nematodes, supporting its status as a new species of Cryphodera. The new species showed a close relationship with C. brinkmani.

Summary In a recent survey of plant-parasitic nematodes associated with forest in China, three species of Paratylenchus, including P. aculentus, P. leptos and P. rostrocaudatus, were found. Paratylenchus leptos and P. rostrocaudatus are new records for China and the male of P. rostrocaudatus is described for the first time. Morphological descriptions, morphometrics and light microscopic photos are provided for these three species. Molecular characterisation of these species using ribosomal RNA (rRNA) D2-D3 expansion domains of large subunit (LSU D2-D3), internal transcribed spacer (ITS) and small subunit (SSU) sequences are also given. Except for the ITS sequence of P. aculentus, other sequences were amplified for the first time. Phylogenetic relationships within the genus Paratylenchus are discussed as inferred from the analyses of LSU D2-D3, ITS and SSU.

The complete mitochondrial genome (mitogenome) ofAphelenchoides besseyiis 16 216 bp in size and has the typical organisation of nematode mitogenomes of Chromadorea, including 12 protein-coding genes (PCGs), two rRNA genes, 22 tRNA genes and the AT-rich non-coding region. The nucleotide composition of the mitogenome ofA. besseyiis AT-biased (80.0%) and the AT skew is −0.289. The most common start codon forA. besseyiis ATT. Thenad3andnad4Lgenes have an incomplete stop codon consisting of just a T and the other PCGs stop with the full stop codons. All the tRNA genes display a non-typical cloverleaf structure of mitochondrial tRNA. The AT-rich non-coding region contains ten tandem repeat units with four different regions. Phylogenetic analysis based on concatenated amino acid sequences of 12 protein-coding genes showed that three Tylenchomorpha species, includingA. besseyi,Bursaphelenchus mucronatusandB. xylophilusfrom the superfamily Aphelenchoidea, are placed within a well-supported monophyletic clade, but far from the other six Tylenchomorpha speciesMeloidogyne chitwoodi,M. graminicola,M. incognita,Pratylenchus vulnus,Heterodera glycinesandRadopholus similisof Tylenchoidea. This phylogeny suggests thatAphelenchoideshas a close relative relationship withBursaphelenchusand that the Tylenchomorpha is not monophyletic.

Heterodera hainanensis n. sp. is described and illustrated from bamboo (Phyllostachys pubescens) based on morphology and molecular analyses of rRNA D2D3 region of LSU and ITS. This new species belongs to the Afenestrata group and is characterised by lemon-shaped cyst with prominent vulval cone and vulval cone without fenestration and bullae but with weak and furcate underbridge. The second-stage juvenile (J2) has two lip annuli, a 15.8-17.5 μm long stylet with rounded knobs sloping slightly posteriorly, three incisures in the lateral field and a conical tail with hyaline portion forming 52.3-71.1% of the tail length. Heterodera hainanensis n. sp. most closely resembles species in the Afenestrata group but is distinguished from these species by a number of characters, including cyst shape and size, the presence of an underbridge, vulval slit length, J2 stylet length, stylet knobs shape, incisure number and lip annule number. Molecular analysis reveals that this species has unique LSU D2D3 and ITS rRNA sequences and RFLP-ITS-rRNA profiles, and it is most closest to H. koreana in dendrograms inferred from both markers. A key to all species of the Afenestrata group is presented.