Helgenema lamia, Smales, 2021

Durette-Desset, Marie-Claude & Digiani, María Celina, 2023, Revision of the genera of Heligmonellidae (Nematoda, Heligmosomoidea), parasitic in Muridae from New Guinea, Parasite (Paris, France) 30 (63), pp. 1-34 : 27

3.10.1.2 Helgenema lamia ( Figs. 10D–10F )

3.10.1.2.1 Synlophe (based on sections from two males and two females). Sections analyzed herein are within proximal body: male ( Fig 1b /10D), and at midbody: male ( Fig. 1f /10E) and female ( Fig. 1a /10F); lateral cords illustrated in Figure 1a / 10F; ridges numbered in Figure 1f /10E.

In all sections careen absent and left cuticular dilatation present. Axis of orientation described as oblique (from right-ventral to left-dorsal) in [ 44].

Within proximal body: in Figure 10D (male), 14 ridges irregularly spaced, unequal in size. Four gaps on left side (arrowheads); ridges medium sized and subequal, except one left ridge, large. Ridges oriented in two opposite directions from right-ventral quadrant to left, starting from a pair of divergent ridges (curved arrows) but not clear convergent ridges on left-dorsal quadrant; the two ridges flanking left ridge (dorsally and ventrally) slightly larger than remaining ridges and perpendicular to body surface.

At midbody: in both sexes, 15 ridges irregularly spaced and unequal in size.

Figure 10E (male): three gaps on left side (arrowheads) between ridges 2’ and 1’, 1’ and 1, 1 and 2; ridge 1’ large, ridge 1 medium-sized; other dorsal ridges small, regularly spaced and oriented from right to left, with ridges 5 and 6 larger; ventral ridges medium sized, regularly spaced and oriented from right to left, with ridges 6’ and 7’ larger and ridge 8’ minute; axis of orientation drawn in [ 44] passes between ridges 7 and 8’ (whose tips not divergent) then between ridges 1’ and 1.

Figure 10F (female): three gaps on left side (arrowheads); left ridge largest; first dorsal ridge on the left larger than other dorsal ridges, small and regularly spaced. On ventral side, ridges small, subequal in size and much thinner than in male section. Dorsal and ventral ridges disparately oriented.

3.10.1.2.2 Bursa (illustrated in [ 44]: Fig. 1L ). Figure 1L in captions (corresponds to “i” on Fig. 1 ). Entire bursa with left lobe folded ventrally, dorsal view. Bursa dissymmetrical with left lobe larger. From the written description [ 44], bursal pattern of type 2-3.

3.10.2 Comments

Figures

Figure 1. Genus Melomystrongylus Smales, 2009. Body sections. A–D Melomystrongylus sepikensis Smales, 2009. A, B within proximal body. A male, B female; C, D at midbody. C male, D, female. E–H Melomystrongylus somoroensis Smales & Heinrich, 2010. E, F within proximal body. E male, F female. G, G’ at midbody, male. H female “at posterior end of midbody” (sic). Sources: A–D redrawn from [30]. E–H redrawn from [45]. G’ modified figure, reversed on its frontal axis with respect to the original.

Figure 10. Genus Helgenema Smales, 2020. Body sections. A–C’ Helgenema keablei. A, A’ within proximal body, female. B–C’ at midbody. B, B’, male. C, C’ female. D–F’ Helgenema lamia Smales, 2021. D within proximal body, male. E–F’ at midbody. E, E’ male, F, F’, female. Sources: A–C redrawn from [43]. D–F redrawn from [44]. A’–C’, E’, F’ modified sections: A’ reversed on its frontal axis with respect to the original, B’ reversed on frontal axis then rotated ca. 15° clockwise with respect to the original. C’, E’, F’ re-numbering of ridges.