A new species of the genus Paurodontella Husain & Khan, 1968 (Nematoda: Hexatylina, Sphaerularioidea) with its molecular phylogenetic study

Abstract

Abstract A new species of the genus Paurodontella, Paurodontella minora n. sp., collected from Alborz Province, Iran, is described and illustrated based on morphological and molecular characters. The new species is characterized by its body length of 393 (350–438) μm and 380 (n = 1) μm in female and male, respectively, 6–7 incisures in lateral field, lip region annulated and continuous with body contour, and total stylet 6.1 (5.5–7.0) μm long. Basal pharyngeal bulb with small posterior extension projecting reaching to the intestine. Excretory pore situated at the level of basal pharyngeal bulb region, no post-uterine sac, conical tail, narrowing to a rounded tip, and rare male with slender tylenchoid spicules and adanal bursa. The new species comes close in morphology and morphometrics to four known species of the genus, namely Paurodontella asymmetrica, Paurodontella balochistanica, Paurodontella densa and Paurodontella niger. In molecular phylogenetic analyses using D2–D3 expansion segments of the large subunit rDNA gene sequence, P. minora n. sp. formed a major clade with species of the genera in the family Sphaerulariidae (Paurodontella, Paurodontoides, Veleshkinema and Sphaerularia) and a sister relation with the members in the families Neotylenchidae and Anguinidae with the same clade support values in Bayesian inference.