Description and molecular phylogeny of one new and one known needle nematode of the genus Paralongidorus (Nematoda: Longidoridae) from grapevine in Portugal using integrative approach

Abstract

A new and a known longidorid nematode, Paralongidorus lusitanicus n. sp. and Paralongidorus plesioepimikis, are described and illustrated from populations extracted from soil associated with grapevine (Vitis vinifera L.) from Escaroupim and Pó (central-Western Portugal), respectively. The new needle nematode P. lusitanicus n. sp. is characterised by a very large body size (8072-12,022 μm), an expanded and rounded lip region, ca 30 μm wide, with a clear constriction followed by a depression posterior to the amphidial aperture, amphidial fovea very large (11.0-19.0 μm), stirrupshaped, with conspicuous slit-like aperture as shown in scanning electron microscopy studies, a very long and flexible odontostyle (180.0-223.0 μm), guiding ring located at 28.0-41.5 μm from anterior end, vulva anterior to the mid-body (34-41%), a dorsally convex-conoid tail with rounded terminus (29-42 μm long), bearing two or three pairs of caudal pores and males common (ratio 1:1.6 females) with spicules ca 80 μm long. Morphological and morphometric traits for P. plesioepimikis fit well with the original description, and is reported for the first time in Portugal. Integrative diagnosis of both species was completed with molecular data obtained using D2-D3 expansion segments of 28S rDNA, ITS1-rDNA and partial 18S-rDNA. The phylogenetic relationships of these species with other Paralongidorus spp. using these three molecular markers indicated that P. lusitanicus n. sp. clustered together with other Paralongidorus spp. forming a sister clade with P. plesioepimikis, both of them sharing a large body, long odontostyle, an anteriorly located vulva and an expanded and rounded lip region with a clear constriction followed by a depression posterior to the amphidial aperture.

Studies on Longidorus iberis (Escuer & Arias, 1997) n. comb. (Nematoda: Longidoridae) from Spain

“…Phylogenetic analyses based on three rDNA molecular markers (D2-D3 expansion domains of 28S rRNA gene, ITS1 region and the partial 18S rRNA) and mitochondrial DNA coxI resulted in a general consensus of species phylogenetic positions for the majority, and were generally congruent with those given by previous phylogenetic analysis ( Gutiérrez-Gutiérrez et al, 2018;Archidona-Yuste et al, 2019;Cai et al, 2020;Inserra et al, 2021). Phylogeny based on several ribosomal and mitochondrial markers also confirm the SEM results, clearly separating L. iberis n. comb.…”

Morphological and Molecular Characterization of Paralongidorus sali Siddiqi, Hooper, and Khan, 1963 with a Description of the First-Stage Juvenile and Male of Longidorus jonesi Siddiqi, 1962 from China

“…10). This tree is similar to the most recent phylogenetic analysis showed by Gutiérrez-Gutiérrez et al (2017), Barsi andLuca (2017), and showing P. bikanerensis in a position outside of the main clade for Paralongidorus. Longidorus jonesi is well-related phylogenetically to accession described from Japan (KF552069) .…”

“…The major difference used to separate Longidorus, Longidoroides, and Paralongidorus is the shape of amphids (pouch like in Longidorus and Longidoroides vs. funnel/stirrup shaped in Paralongidorus) and the opening of amphidial aperture (pore-like in Longidorus vs. slit-like in Longidoroides and Paralongidorus) (Oliveira and Neilson, 2006). Several new species of Paralongidorus have published with complete molecular characterization and scanning electron microscopy (SEM) observations (Palomares-Rius et al, 2008Pedram et al, 2012;Gutiérrez-Gutiérrez et al, 2017;Barsi and Luca, 2017) which enables the discrimination between Longidorus and Paralongidorus species. However, there is no molecular evidence to distinguish Longidoroides species which leaves the status of this Ruihang Cai, 1 Munawar Maria, 1 Nan Qu, 1 Pablo Castillo, 3 genus as junior synonym of Paralongidorus as suggested by Decraemer and Coomans (2007).…”

Description of Longidorus bordonensis sp. nov. from Portugal, with systematics and molecular phylogeny of the genus (Nematoda, Longidoridae)

“…Subsequently, they were centrifuged in 18 µl of solution containing 10 µl ddH 2 O, 6 µl 10× PCR buffer, and 2 µl of proteinase K (20 mg/ml) (Nalgene), and frozen at −80 °C (15 min). Samples were mixed for 15 sec and PCR assays were conducted as described by Gutiérrez-Gutiérrez et al (2018). The tubes were incubated at 57 °C (1 h), 65 °C (1 h), and 95 °C (15 min).…”