A new orthopteran-parasitizing horsehair worm, sp. n., with a redescription of and novel host records from Taiwan (Nematomorpha, Gordiida).

A description of a new species of horsehair worm, , a redescription of , and novel host records for the latter are provided. is morphologically similar to with moderately flat areoles on its tail tips, but is distinguishable by small mid-body ornamentations. Despite the distinct differences in the post-cloacal crescents between 14 male samples, their conspecific status, along with that of nine female samples, was upheld by a phylogenetic comparison of partial cytochrome oxidase subunit I (COI) sequences. is another common horsehair worm species in Taiwan, which was previously believed to specifically parasitize mantids. However, in this study, five were observed emerging from an mantid, and two long-horned grasshopper hosts ( sp. and ). These five worms showed high degrees of similarity in COI sequences and morphology, but one of these individuals bore abnormal crowned areoles, which has never been observed in , and may be attributed to the incomplete development of this particular individual.