Longidorus sabalanicus n. sp. is described and illustrated based on morphological, morphometric and molecular studies of two populations from north-western Iran. It was recovered from the rhizosphere of meadow grasses in East Azarbaijan province and the rhizosphere of Astragalus sp. in Zanjan province. The new species is characterised by having a medium sized body, 3.8–5.1 mm in females and 3.6–4.7 in males; lip region anteriorly flattened, laterally rounded, set off from body contour by a slight depression; amphidial fovea pocket-shaped, without basal lobes; guiding ring at 25–30 μm from anterior end; odontostyle moderately long, 73.0–85.5 μm and odontophore weakly developed, 50.0–67.4 μm long; female reproductive system containing sperm, vulva located at 50–54% of body length; tail bluntly conoid, 41.0–55.0 μm long; males common in both populations, with 54.0–68.5 μm long spicules and seven to ten ventromedian precloacal supplements anterior to the adanal pair; and four juvenile developmental stages present. The alpha-numeric codes for identifying the new species are: A23-B2-C2-D3-E1-F2-G1-H12-I2-J1-K7. Morphologically, the new species most closely resembles to L. moniloides, L. rotundicaudatus, L. tabrizicus, L. artemisiae, L. asiaticus, L. behshahrensis, and L. elongatus. Morphological and morphometric differences of Longidorus sabalanicus n. sp. and the aforementioned species are discussed. In addition to morphological and morphometric data, molecular comparison analyses based on partial 18S rRNA, D2-D3 expansion segments of 28S rRNA and ITS1 region sequences, indicate that L. sabalanicus n. sp. is separated from other species and it is related phylogenetically with L. behshahrensis.

Longidorus sabalanicus n. sp。基于对来自伊朗西北部的两个种群的形态学、形态测量学和分子研究进行了描述和说明。从东阿塞拜疆省草甸草根际和黄芪根际回收sp。在赞詹省。新种的特点是体型中等，雌性3.8-5.1毫米，雄性3.6-4.7；唇部前部扁平，侧面圆润，与身体轮廓有轻微的凹陷；两栖中央凹袋状，没有基部裂片；距前端 25-30 μm 的导向环；齿状体中等长，73.0-85.5 μm，牙体弱发育，50.0-67.4 μm；含有精子的女性生殖系统，外阴位于体长的 50-54%；尾钝圆锥形，长 41.0-55.0 μm；雄性在两个种群中都很常见，有 54.0-68.5 微米长的针状体和 7 到 10 个腹中线前泄殖腔补充物位于 adanal 对前面；并且存在四个青少年发育阶段。用于识别新物种的字母数字代码为：A23-B2-C2-D3-E1-F2-G1-H12-I2-J1-K7。形态学上，L. moniloides，L. rotundicaudatus，L. tabrizicus，L. 青蒿, L. asiaticus , L. behshahrensis和L . 细长鱼 Longidorus sabalanicus n的形态和形态学差异。sp。并讨论了上述物种。除了形态学和形态测量数据，基于部分 18S rRNA、28S rRNA 的 D2-D3 扩展片段和 ITS1 区域序列的分子比较分析表明L. sabalanicus n. sp。与其他物种分离，并在系统发育上与L相关。白沙尔种