Schistonchus hirtus n. sp. (Nematoda: Aphelenchoididae), an associate of Ficus hirta in China

Abstract

Abstract A nematode recovered from syconia of Ficus hirta from Guangzhou, P. R. China, during a survey of nematode biodiversity from 2007 to 2009, is described herein as Schistonchus hirtus n. sp. and is differentiated by a combination of morphological characters, including excretory pore (EP) located near the metacorpus, a short post-uterine sac (PUS) (0.5 vulval body diam. (VBD) long), rose thorn-shaped spicules, amoeboid sperm, absence of gubernaculum, three pairs of subventral papillae on the male tail, host-Ficus and host-wasp species and DNA sequence data. Morphologically, S. hirtus n. sp. is close to S. centerae, S. altermacrophylla, S. aureus, S. laevigatus and S. virens based upon the length of the PUS (about 0.5 VBD long). However, the relative position of the EP in S. hirtus n. sp. is very different from these species (near metacorpus vs near head). With regard to the EP character, S. hirtus n. sp. is very similar to S. macrophylla, S. guangzhouensis and S. caprifici where the EP is at metacorpus level. However, S. hirtus n. sp. differs from S. macrophylla and S. guangzhouensis by possessing a shorter PUS and smaller spicules, and differs from S. caprifici by a shorter female stylet and smaller spicules. Schistonchus hirtus n. sp. was easily differentiated from other sequenced species by the proportion of parsimony informative changes in the partial small subunit rRNA gene (SSU) and D2/D3 expansion segments of the large subunit rRNA gene (LSU). Phylogenetic analysis with SSU sequences suggests that S. hirtus n. sp. is in a highly supported monophyletic clade with Aphelenchoides and Laimaphelenchus and is polyphyletic to other sequenced Schistonchus species. With LSU sequence data, it forms a clade with S. caprifici and they appear polyphyletic relative to S. guangzhouensis, S. centerae, S. aureus, S. laevigatus and S. virens.