Hirschmanniella maritima n. sp. (Nematoda: Pratylenchidae) - a New Nematode Species Parasitizing Baltic Plants in Poland.

Hirschmanniella maritima n. sp. was recovered from the roots of Potamogeton perfoliatus L. plants collected in several locations along the Baltic coast (from the Puck Bay to the Vistula Lagoon) in Poland. H. maritima n. sp. is characterized by a long (L = 1787 μm-3085 μm) body; anteriorly rounded or slightly flattened lip region with four to six lip annuli; medium stylet (19.5 μm-24.5 μm) with large, oval knobs directed approximately laterally; excretory pore located posterior to pharyngo-intestinal junction; intestine partially overlapping rectum; medium-sized spicules (34.0 μm-43.2 μm); gubernaculum slightly arcuate, narrow with hook-shaped distal part; elongate-conoid tail (c' = 4.7-8.1); and tail end irregular in size and shape, without annulations, but with a pointed terminus up to an axial mucro-like projection. Inside the roots of P. perfoliatus, the nematodes were found in intercellular spaces surrounded by degraded cortex cells. Morphological and 28S rDNA-based phylogenetic molecular analyses showed H. maritima n. sp.'s similarity to H. santarosae and H. pomponiensis, with a strong sister relationship between these three species and the clade encompassing H. diversa and H. halophila. The mtCOI-based phylogenetic analysis confirmed a close relationship between H. maritima n. sp. and H. diversa.