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Systematics, phylogeny and biogeography
RESEARCH ARTICLE

Molecular phylogenetic analysis and comparative morphology resolve two new species of olive-tree soil related dagger nematodes of the genus Xiphinema (Dorylaimida : Longidoridae) from Spain

Antonio Archidona-Yuste A , Juan A. Navas-Cortés A , Carolina Cantalapiedra-Navarrete A , Juan E. Palomares-Rius A and Pablo Castillo A B
+ Author Affiliations
- Author Affiliations

A Institute for Sustainable Agriculture (IAS), Spanish National Research Council (CSIC), Campus de Excelencia Internacional Agroalimentario, ceiA3, Avda. Menéndez Pidal s/n, 14004 Córdoba, Spain.

B Corresponding author. Email: p.castillo@csic.es

Invertebrate Systematics 30(6) 547-565 https://doi.org/10.1071/IS16002
Submitted: 5 January 2016  Accepted: 19 April 2016   Published: 13 December 2016

Abstract

The genus Xiphinema constitutes a large group of ~275 species of polyphagous, plant-ectoparasitic nematodes that are distributed almost worldwide. Some species affect agricultural crops by feeding directly on root cells as well as by transmitting nepoviruses. Despite their agricultural importance, species discrimination in Xiphinema is difficult, leading to potential misidentification. Integrative taxonomy, based on the combination of molecular analyses and morphology, constitutes a new insight into Xiphinema species identification. In this study we describe two new species of Xiphinema from the Iberian Peninsula (X. macrodora, sp. nov. and X. oleae, sp. nov.) associated with cultivated and wild olive trees. Both species have specific rRNA sequences. Morphologically, Xiphinema macrodora, sp. nov. is characterised by a very long body (7.2–8.7 mm), a very long odontostyle and odontophore (190–206 and 105–120 µm, respectively), and a well developed pseudo-Z-organ, comprising 8 to 12 sclerotised bodies. Xiphinema oleae, sp. nov. is characterised by an odontostyle and an odontophore 136–149 and 65–80 µm long, respectively, and a well developed Z-organ with refractive inclusions (3–5), variable in shape. Additionally, X. macrodora, sp. nov. has the longest body size, and the longest odontostyle and odontophore of any Xiphinema, whereas X. oleae, sp. nov. is the first species with a well developed Z-organ from the Iberian Peninsula.

http://zoobank.org/urn:lsid:zoobank.org:pub:E4CE8711-22EF-40E4-9D39-6FE962F25225

Additional keywords: Bayesian inference, D2–D3 rRNA, integrative taxonomy, ITS1.


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