First Reports, Morphological, and Molecular Characterization of Longidorus caespiticola and Longidorus poessneckensis (Nematoda: Longidoridae) from Ukraine.

Seven needle nematode species of the genus Longidorus have been reported in Ukraine. Nematological surveys for needle nematodes were carried out in Ukraine between 2016 and 2017 and two nematode species of Longidorus (L. caespiticola and L. poessneckensis) were collected from natural and anthropogenically altered habitats on the territory of Opillia and Zakarpattia in Ukraine. Nematodes were extracted from 500 cm3 of soil by modified sieving and decanting method. Extracted specimens were processed to glycerol and mounted on permanent slides and subsequently identified morphologically and molecularly. Nematode DNA was extracted from single individuals and PCR assays were conducted as previously described for D2-D3 expansion segments of 28S rRNA. Sequence alignments for D2-D3 from L. caespiticola showed 97%-99% similarity to other sequences of L. caespiticola deposited in GenBank from Belgium, Bulgaria, Czech Republic, Russia, Slovenia, and Scotland. Similarly, D2-D3 sequence alignments from L. poessneckensis, showed 99% to other sequences of L. poessneckensis deposited in GenBank from Slovakia and Czech Republic. Morphology, morphometry, and molecular data obtained from these samples were consistent with L. caespiticola and L. poessneckensis identification. To our knowledge, these are the first reports of L. caespiticola and L. poessneckensis in Ukraine, extending the geographical distribution of these species.