Paraheligmonelloides amplicaudae, Smales & Heinrich, 2010

Smales, L. R. & Heinrich, B., 2010, Gastrointestinal nematodes of Paramelomys rubex (Rodentia: Muridae) from Papua Indonesia and Papua New Guinea with the descriptions of three new genera and four new species of Helligmonellidae and Herpetostrongylidae (Nematoda: Trichostrongylida), Zootaxa 2672 (1), pp. 1-28 : 14-16

Paraheligmonelloides amplicaudae sp. nov.

( Figs 66–81 )

Type host. Paramelomys rubex (Thomas)

Site in host. Small intestine.

Material examined. Holotype male, allotype female from Paramelomys rubex Urong Forest, Mokwan area, Arfak Mts (1° 6´S; 133° 56´E) Papua, Indonesia, coll. T. Flannery & L. Szalay 10. x. 1992, AM W.36790, W.36791; paratypes 2 males, 5 females same data AM W.36792.

Etymology. The specific name refers to the enlarged posterior body of the female.

Description. General: Small worms, lightly coiled; prominent cephalic vesicle present with about 7–8 annulations; buccal capsule vestigial. Mouth opening triangular with rudimentary lips; labial and cephalic papillae not observed. Oesophagus claviform. Nerve ring, deirids and excretory pore close together in mid oesophageal region. Synlophe (based on sections from 7 worms) of pointed longitudinal cuticular ridges in both sexes extends from posterior margin of cephalic vesicle to immediately anterior to bursa or vulva; 15–16 ridges in anterior, 20–24 in mid body, 16–18 in posterior body. Axis of orientation of ridges from ventral right to dorsal left, about 55–60° from sagittal plane in mid body; 10–11 ridges dorsal side, 9–12 ridges ventral side; ridges 1´larger than ridges 1; ridge 1´hypertrophied in female mid body. Ridges 8–11, male, 8-10, female, larger than ridges 2–7; ridges 2´–11´smaller than ridges 2–11. Ridges becoming smaller and losing orientation posteriorly.

Male: (Measurements of 3 specimens) Length 2150–2200, maximum width 63–69. Cephalic vesicle 33– 36 long. Oesophagus 280–440 long; nerve ring 190, deirids, excretory pore 185 from anterior end. Bursa (based on 3 worms) asymmetrical, with left lobe slightly larger, pattern of rays 2–3; rays 2, 3 diverge distally, recurved ventrally; rays 4, 5, 6 recurved dorsally; rays 4, 5, more stout than rays 6; rays 2, 3 more slender than rays 4, 5; rays 4, 5 longest. Dorsal lobe with median notch, shorter than lateral lobes; dorsal trunk bifurcates at about 2/3 its length, each branch dividing again at distal tip; terminal divisions, rays 9, 10, symmetrical, rays 8 arising at same level from dorsal trunk proximally to division of dorsal ray. Genital cone short, rounded, ventral lip with unpaired papilla 0, dorsal lip with paired papillae 7. Spicules simple, filiform, slightly curved distally, tips pointed 280–365 long. Gubernaculum 27–29 long.

Female: (Measurements of 6 specimens) Length 2510–3250 (2500), maximum width 67–98 (74). Cephalic vesicle 33–39.5 (36) long. Oesophagus 310–366 (341) long; nerve ring 170, deirids, excretory pore 200 from anterior end. Monodelphic ovejector, vulva close to posterior end, 49–56 (52) from tail tip; vagina about 20, vestibule longest element, 40, sphincter 30, infundibulum 30 long. Posterior body at region of ovejector enlarged, with praepuce. Tail short, reflected ventrally 13–25.5 (18) long. Tail tip pointed with paired papillae. Eggs thin shelled, ellipsoidal, 8–9 in utero 59.5 by 33.

Remarks. Characterized by having a synlophe without a carene, ridge1´larger than ridge 1, an asymmetric bursa and rays 8 arising proximally to the branching of the dorsal ray Paraheligmonelloides amplicaudae n. sp. falls within the genus Paraheligmonelloides as defined by Ow Yang et al. (1983) and Hasegawa et al. (1999). Paraheligmonelloides amplicaudae differs from all its congeners in having ridge1´of the synlophe hypertrophied only on the female mid body and having the posterior body at the region of the ovejector enlarged. With a synlophe of 21–24 ridges on the mid body P. amplicaudae is closest to P. singauwaensis with 20–23 ridges but further differs from it in being less robust, males 63–69 wide compared with 73–100, having the dorsal lobe of the bursa shorter than the lateral lobes and a shorter gubernaculum 27– 29 long compared with 29–35.5.

Figures

FIGURES 66–81. Paraheligmonelloides amplicaudae n. sp. 66. female, anterior end, showing synlophe ridges; 67. female, anterior end, lateral view; 68. male, transverse section, anterior body; 69. female, transverse section, anterior body; 70. male, transverse section, anterior body; 71. female, transverse section, mid body; 72. male, transverse section, posterior body; 73. female, posterior end ventral view; 74. spicule, proximal end; 75. genital cone, lateral view; 76. female, transverse section, posterior body; 77. gubernaculum, lateral view; 78. spicule tips, distal end 79. female, posterior end lateral view; 80. bursa, flattened out 81. bursa, dorsal view, lateral lobes curled in. Scales are in µm.