Axonchium
Creators: name: Naz, Tabbasam
name: Ahmad, Wasim
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Nematoda
Adenophorea
Dorylaimida
Belondiridae
Axonchium

description: Key to species of the genus Axonchium based on males
(modified after Coomans & Nair, 1975)
1 Lip region offset with incompletely separated lips............................................................ 2
- Lip region offset with well separated lips................................................................... 4
2 Body 1.5 mm or less long; odontostyle 8–9 µm; spicules less than 40 µm.........................................3
- Body more than 1.5 mm; odontostyle 10–12 µm; spicules 55–57 µm........................................ vallum
3 Spicules 36–39 µm; ventromedian supplements 7; lateral guiding pieces 13–15 µm........................... shamimi
- Spicules 32 µm; ventromedian supplements 2; lateral guiding pieces 10 µm.................................. siddiqii
4 Over 150 lateral and over 80 ventral body pores; 7–10 caudal pores; spicules very stout, 52–71 µm long with almost straight ventral side; anterior pharynx very slender............................................................ variabile
- Body pores less numerous; up to 4 caudal pores............................................................. 5
5 First ventromedian supplement above the range of spicules.....................................................6
- First ventromedian supplement within the range of spicules or just in front of proximal end of spicules................. 15
6 Ventromedian supplements only two......................................................... .. noreasum n. sp.
- Ventromedian supplements 4 or more..................................................................... 7
7 Tail about 1.2 anal body widths long; spicules short and stout, with greatest width in distal half and complex median piece without posterior projection; lateral guiding pieces less than 10 µm, very heavily sclerotized, without distal bifurcation............................................................................................... latespiculatum
- Tail one or less than one anal body width long, spicules stout with simple median piece and posterior projection at the distal end; lateral guiding pieces more than 10 µm, with distal bifurcation.............................................. 8
8 Spicules longer, 1.7–1.9 anal body widths long, ventromedian supplements 4............................. parasaccatum
- Spicules 1.5 or less anal body widths long; supplements 4 or more............................................... 9
9 Spicules bent ventrally with bluntly rounded distal ends, inner walls heavily sclerotized............................. 10
- Spicules arcuate, lightly sclerotized...................................................................... 12
10 Spicules 1.2 anal body widths long, proximal end of spicules less thickened, middle piece thin at most of its length, swollen near distal end.............................................................................. thoubalicum
- Spicules 1.2–1.4 anal body widths long, middle piece of spicule not swollen near distal end.......................... 11
11 Body 2.1–2.8 mm long; spicules bent ventrally at right angle, stout with blunt posterior projection at distal end, inner walls of spicules sometimes crenate; 5–10 ventromedian supplements............................................... heynsi
- Body 1.4–1.7 mm long; spicules slightly ventrally curved without posterior projection at distal end, inner walls of spicules uni- formly thickened, 4–6 ventromedian supplements...................................................... phukani
12 Body 1.6 mm long; expanded part of pharynx 50–54% of total neck length; lateral guiding pieces with sclerotized bifid tip................................................................................................ hosakodii
- Body 1.7–2.04 mm long; expanded part of pharynx more than 60% of total neck length; lateral guiding pieces with bifurcated distal ends.......................................................................................... 13
13 Body L shaped; 6–7 irregularly spaced ventromedian supplements; lateral guiding pieces swollen with diverging distal ends; tail with three caudal pores on each side........................................................... transkeiense
- Body slightly curved ventrad; 5–7 regularly spaced ventromedian supplements; lateral guiding pieces with bifurcated distal ends; tail with two caudal pores on each side............................................................... 14
14 Spicules 1.2 anal body width long; prerectum 11–14 anal body widths long; 6–7 regularly spaced ventromedian supplements; tail one anal body width long.................................................................... khasianum
- Spicules 1.5 anal body width long; prerectum six anal body widths long; 5 regularly spaced ventromedian supplements; tail about 0.7 times anal body width long........................................................ meghalyense n. sp.
15 Spicules slender...................................................................................... 16
- Spicules robust...................................................................................... 18
16 Spicules 50–56 µm long; ventromedian supplements 5–6................................................ sabulum
- Spicules above 70 µm long; ventromedian supplements 7–12.................................................. 17
17 Guiding ring ‘double’; 7–11 irregularly spaced ventromedian supplements; spicules 78–81 µm, ventrally arcuate, head of spic- ule distinctly ventrally curved; lateral guiding pieces arcuate............................................. sinclairi
- Guiding ring ‘single’; 8–12 ventromedian supplements in two groups; spicules 73–79 µm, ventrally arcuate, head of spicule not ventrally curved; lateral guiding pieces slender, straight............................................... dubium
18 Body 1.9–2.0 mm long; spicules 66–70 µm long; lateral guiding pieces rod-like and provided with a distal inward projection............................................................................................. manalicum
- Body 2.2 mm or less long; spicules 55 µm or less long; lateral guiding pieces without distal inward projection........... 19
19 Body 1.2–1.3 mm long; spicules less than 33 µm long....................................................... 20
- Body 1.4–2.2 mm long; spicules more than 39 µm long...................................................... 21
20 Spicules unusually wide at the blunt distal end; lateral guiding pieces with bifid distal ends; tail with two caudal pores on each side........................................................................................... elegans
- Spicules with narrow distal end; lateral guiding pieces with blunt distal ends; tail with three caudal pores on each side................................................................................................... cooverkolli
21 Spicules wide at the distal end.......................................................................... 22
- Spicules with narrow distal end......................................................................... 24
22 Spicules 39–44 µm or 1.0–1.1 anal body width long with very broad and truncate distal end.................... accatum
- Spicules over 1.5 anal body widths long with blunt distal end.................................................. 23
23 Nine ventromedian supplements in two groups of three and six; lateral guiding pieces less sclerotized.............. eletum
- Six to seven irregularly spaced ventromedian supplements; lateral guiding pieces heavily sclerotized............ neoeletum
24 Ventromedian supplements 10–13; lateral guiding pieces slender; prerectum 9.4–12.2 anal body widths long; tail with four caudal pores on each side...................................................................... propinquum
- Ventromedian supplements less than ten; lateral guiding pieces not so slender; prerectum less than ten anal body widths long; tail with two caudal pores on each side.................................................................... 25
25 Prerectum 4.3–7.4 anal body widths long; lateral guiding pieces simple with bifurcated distal ends............. amplicolle
- Prerectum 8.7–9.9 anal body widths long; lateral guiding pieces simple with thickened distal ends....... metobtusicaudatum
description: Published as part of Naz, Tabbasam & Ahmad, Wasim, 2012, Description of two new and five known species of the genus Axonchium Cobb, 1920 (Nematoda: Dorylamida) from India with diagnostic compendia and keys to species of the genera Axonchium and Syncheilaxonchium Coomans & Nair, 1975, pp. 1-37 in Zootaxa 3264 on pages 34-35, DOI: 10.5281/zenodo.215075