Dorcopsinema longispicularis, Purwaningsih, Endang & Smales, Lesley R., 2014

Purwaningsih, Endang & Smales, Lesley R., 2014, New species of Dorcopsinema and P aralabiostrongylus (Nematoda: Chabertiidae: Cloacininae) from Indonesia, with a key to species of Dorcopsinema, Zootaxa 3857 (4), pp. 591-598 : 593-594

Dorcopsinema longispicularis sp. nov.

( Figs 1–13 , 27, 28)

Description. General: Medium sized worms; body, with fine transverse cuticular striations, widest in mid region, narrower posteriorly. Cephalic extremity with well defined fleshy collar bearing 2 amphids, each on dome-like projection and 4 submedian cephalic papillae. Mouth opening circular, peri-oral cuticle forming 8 sclerotized liplike processes arising within the buccal capsule; 2 lateral processes largest, dorsal, ventral and submedian processes with mucronate tips ( Figs 1 , 27). Buccal capsule wider than deep ( Fig. 2 ). Oesophagus relatively long, cylindrical about 1/3 of body length.Deirids, setate ( Fig. 4 ), 1050 long, and excretory pore just posterior to nerve ring which encircles oesophagus at about 1/5 its length Fig.3 ). Oesophago-intestinal diverticula small, shorter than oesophagus width ( Fig. 3 ).

Male (n=2): Body length 8.25 mm; 10.03 mm, maximum width 185; 200. Buccal capsule depth 118; 130, width 95; 110. Nerve ring 490; 488, deirids 520; 700, excretory pore 620; 690 from anterior end; oesophagus length 2560; 2790. Spicule length 2400; 2570, about 28 % of body length, anterior extremities rounded, distal tips more or less straight, pointed, striated alae extending to tips. Gubernaculum small, rectangular ( Fig. 13 ), length 83, width 40. Bursa small, bursal lobes not separate, dorsal lobe longest, ventral lobes shortest. Ventro-ventral and latero-ventral rays apposed, reaching margin of bursa; externo-lateral ray short, not reaching margin of bursa; medio and postero-lateral rays same length apposed, reaching margin of bursa; externo-dorsal ray arising close to lateral trunk, not reaching margin of bursa, dorsal trunk stout, bifurcating at about 1/3 its length, dorsal rays reaching margin of bursa, lateral branches just proximal to bifurcation, not reaching margin of bursa ( Fig. 10 ). Genital cone prominent, anterior lip large, conical, posterior lip smaller, with 1 large pair, 1 small pair bifid posteriorly directed appendages ( Figs 11, 12 ).

Female (n = 4): Body length 9.6 (8.04 – 12.2) mm, maximum width 214 (200–230). Buccal capsule depth 127 (113–145), width 87 (80–100). Nerve ring 378 (280–550), deirids 523 (300–450), excretory pore 593 (400–770) from anterior end. Oesophagus length 2820 (2450–3530). Vulva anterior to anus, 1081 (1050–1155) from posterior end. Ovejector with infundibulum 165, vestibule 265 about the same length, sphincter longer 465, vagina vera short, straight, thick walled ( Fig. 7 ), length 735. Tail length 834 (620–980), about 7% of body length, with spiked tip ( Figs 5, 6 ). Eggs not found.

Fourth stage larvae (n=4): Length 5418 (5040–5800), width 290 (250–330); oesophagus length 1563 (1440–1620). Fleshy collar not developed at cephalic end, 6 peri oral, lip like processes arise from wall of buccal capsule (Figs. 28); anterior end of intestine developing into diverticula. Tail length 242 (235–250).

Type host: Dorcopsis muelleri (Lesson) (Mammalia: Macropodidae ).

Type locality: Raja Ampat Island, Papua, Indonesia (1º 6´S, 130º 51 E).

Site of infection: stomach.

Prevalence: 1/1 wallabies examined.

Intensity: 10.

Type specimens: Holotype male, allotype female ( MZB Na 641); paratypes, 1

male and 3 females (MZBNa642)

Etymology: The specific name highlights the length of the spicules in this species.

Remarks: The genus Dorcopsinema was erected by Mawson (1977) to accommodate the species D. dorcopsis which had been described by Baylis (1940) as Macropstrongylus dorcopsis from the stomach of the forest wallaby Dorcopsis muelleri . Subsequently, the macropod stomach worms D. dendrolagi Smales, 1982 from the tree kangaroos Dendrolagus goodfellowi Thomas and D. dorianus Ramsay , D. mbaiso Smales, 1997 also from a tree kangaroo D. mbaiso Flannery, Boeadi & Szalay , and D. simile Smales, 1999 from a forest wallaby Dorcopsulus vahheurni Thomas were described. The genus is differentiated from all others in the Cloacininae by the characters of the cephalic end, particularly the wide collar bearing cephalic papillae and amphids and with the perioral cuticle forming six or eight more or less fleshy lip-like processes with broad bases and mucronate at the free ends (Mawson, 1997). Therefore four species are currently recognized in the genus, all occurring only in forest wallabies or tree kangaroos from Papua Indonesia or Papua New Guinea.

With 8 lip-like processes and lateral branches of the dorsal ray arising anterior to the bifurcation of the dorsal trunk Dorcopsinema longispicularis sp. nov. falls closest to D. simile in the key to the species of Dorcopsinema by Smales (1999). Dorcopsinema longispicularis is a smaller worm than D. simile with longer spicules (2400, 2570, 28% body length, compared with 1685–2055, 11% body length) and a relatively longer esophagus, (about 1/3 compared with 1/5 of body length). Dorcopsinema longispicularis further differs from D. simile in the number of pairs of appendages on the posterior lip of the genital cone (2 compared with 3), the form of the spicule tips (straight, pointed with striated alae reaching tips compared with blunt, curved with striated alae not reaching tips), the shape of the female tail (spiked compared with blunt tip) ( Smales, 1999). Dorcopsinema longispicularis occurs in Dorcopsis muelleri from the Raja Ampat Islands, Papua and D. simile in Dorcopsulus vanheurni (Thomas) from Chimbu and Morobe Provinces, Papua New Guinea.

Figures

FIGURES 1 – 13. Dorcopsinema longispicularis sp. nov. from Dorcopsis muelleri (Lesson, 1827). 1, Cephalic end, male, en face view, 2, Cephalic end male, lateral view; 3, Anterior end male, ventral view; 4, Deirid; 5, Posterior end female, lateral view; 6, Female, tip of tail; 7, Ovejector, lateral view; 8, Spicule, proximal end; 9, Spicule, distal end; 10, Copulatory bursa, apical view; 11, Genital cone, dorsal view; 12, Genital cone, lateral view; 13, Gubernaculum. Scale bars 1, 2, 10, 50 µm; 3, 500 µm; 4, 6, 9, 11, 12, 13, 25 µm; 5, 200 µm; 7, 8, 100 µm.