Montistrongylus giluwensis, Smales, 2011

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 : 14

3.3.2.2 Montistrongylus giluwensis

3.3.2.2.1 Synlophe. The indication of the lateral cords in both sexes within the proximal part of the body and the position of the ridge sets and ridge free spaces ( Figs. 3E and 3F ) allows us to re-orientate the sections at midbody. The reversion of the male section on the frontal axis then a slight rotation clockwise ( Fig. 3G’ ) results in both sections (male and female) having the same pattern of ridge sets and ridge-free spaces, but also the same number of ridges in the respective ridge sets, with dorsal ridges less numerous than ventral ones. In Figure 3H, a slight rotation counterclockwise results in an axis of orientation subfrontal ( Fig. 3H’ ).

3.3.2.2.2 Bursa. Unlike the original written description, the illustration of both latero-ventral lobes, highlights the right lobe being clearly larger that the left one. One explanation could be that the lobes illustrated do not belong to the same species. This hypothesis is reinforced by the illustration of two types of dorsal lobe. The first type ( Fig. 10 ) is illustrated independently of the latero-ventral lobes; it is characterized by a right ray 8 extending beyond the level of the division of the dorsal ray. It could be linked to the left lobe (Fig. 12) but this remains hypothetical. The second type (Fig. 13) is illustrated with the right lobe. Even if it is not completely illustrated, it is characterized by a right ray 8 just reaching the level of the division of the dorsal ray. This means that, among the males studied, at least two taxa are present. From the original illustration, the pattern is of type 1-4 in both lobes with a short common trunk of rays 3-6; in the right lobe (Fig. 13) rays 4 to 6 diverge at the same level from their common trunk, in the left lobe, rays 6 diverge proximally to rays 4 and 5.

Figures

Figure 3a. Montistrongylus Smales & Heinrich, 2010. Body sections. A–D’ Montistrongylus ingati Smales & Heinrich, 2010. A–B’ within proximal body. A male, B, B’ female. C–D’ at midbody. C male, D, D’ female. E–H’ Montistrongylus giluwensis Smales, 2011. E, F within proximal body. E male, F female. G–H’ at midbody. G, G’ male, H, H’ female. Sources: A, D redrawn from [45]; E–H redrawn from [33]. B’, D’, G’, H’ modified figures: B’ rotated ca. 75° counterclockwise with respect of the original. D’–H’ reinterpreted orientation of the axis (subfrontal). G’ reversed on its frontal axis then rotated 30° clockwise with respect to the original. H’ rotated ca. 10–20° counterclockwise 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.