Nygolaimoides, Meyl in Andrassy, 1960

Asgari, Mohsen, Mohammadlou, Mahsa, Eskandari, Ali, Abolafia, Joaquín & Peña-Santiago, Reyes, 2025, Description of Nygolaimoides jairajpurii sp. nov. from Iran, a new member of a rare genus (Nematoda, Dorylaimida, Thorniidae), Zootaxa 5660 (1), pp. 111-118 : 116-117

Key to species identification Nygolaimoides

is a homogenenous taxon, with a recognizable morphological pattern. Its species can be separated mainly by small and almost always morphometrical differences. The following key, modified from that published by Zahedi et al. (2016), is useful for their identification.

1a – Monosexual species, with more posterior vulva ( V = 60–61)............................................. pusillus

1b – Bisexual species, with more anterior vulva ( V up to 56)....................................................... 2

2a – Female tail extremely short, 4–5.5 µm long. Spicules 13–17 µm long........................................ albus

2b – Female tail not so short, more than 10 µm long. Spicules 20 µm long or more..................................... 3

3a – Vulva pre-equatorial ( V = 46–50); spicules with visibly broaden head.................................. zarrinensis

3b – Vulva post-equatorial ( V = 49–56); spicules with regular head................................................. 4

4a – Body 1.32–1.57 mm long. Odontostyle 12–13 µm long. Spicules 40–43 µm long …..................... borborophilus

4b – Body less than 1.30 mm long, very exceptionally more. Odontostyle less than 12 µm long. Spicules up to 35 µm long..... 5

5a – Lip region 10–11 µm broad; odontostyle about equal to lip region diameter. Spicules 20–25 µm long...... gubernaculifer

5b – Lip region 12–13 µm broad, or more. Odontostyle distinctly shorter than lip region diameter. Spicules 29 µm long or more. 6

6a – More slender body (a = 34–55). Shorter female tail (7–10 µm, c = 110–163). Male invariably bearing four ventromedian supplements.......................................................................... jairajpurii sp. nov.

6a – Less slender body (a = 25–33). Longer female tail (13–17 µm, c = 53–86). Male bearing two ventromedian supplements, very occasionally one or three............................................................................... 7

7a – Lip region 14.5–16.0 µm broad; odontostyle 11.0–11.5 µm long; female tail 15–17 µm long.................. andrassyi

7b – Lip region 13.0–14.0 µm broad; odontostyle 9–10 µm long; female tail 13–14 µm long...................... fraternus