Paralabiostrongylus rajampatensis, 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 : 594-597

Paralabiostrongylus rajampatensis sp. nov.

( Figs 14–25 , 29)

Description. General: Robust worms, cuticle with fine transverse striae. Cephalic extremity square in cross section, mouth opening surrounded by 6 fleshy lips, each with paired lateral flaps, lateral lips largest, bearing amphids, 4 submedian lips with pointed tips, cephalic collar distinct, with 4 setate submedian papillae ( Figs 14 , 29). Buccal capsule more or less cylindrical, thick walled, deeper than wide ( Fig.15 ). Oesophagus long cylindrical, about 1/4–1/3 body length. Oesophago -intestinal diverticula well defined, about same length as width of oesophagus ( Fig. 16 ). Two cuticular frills surround cephalic extremity between cephalic collar and level of nerve ring ( Figs 16 , 29). Nerve ring surrounds oesophagus at about 1/4 its length, deirid anterior to nerve ring, excretory pore posterior to nerve ring.

Male (n=1): Body length 10.8 mm width 730. Buccal capsule depth 59, width 50. Deirids setate 59.5, long, 603, nerve ring 630, excretory pore 770 from anterior end; oesophagus length 2650 long. Bursal lobes not separate, dorsal lobe longest, ventral lobes shortest. Ventro-ventral and ventro-lateral rays apposed reaching margin of bursa; externo lateral ray divergent, reaching margin of bursa; medio-lateral and postero-lateral rays apposed, reaching margin of bursa; externo- dorsal ray arising close to dorsal trunk, not reaching margin of bursa ( Fig 17 ); dorsal trunk stout, giving off pair of short lateral branches before bifurcating at about 4/5 its length, close to distal end ( Fig.18 ). Spicule 1080 long, about 1/10 body length, proximal ends irregularly knobbed, distal tips slightly curved, blunt, striated alae extend to spicule tips ( Figs 19, 20 ). Gubernalculum trapezoidal ( Fig. 21 ). Genital cone not prominent, anterior lip conical, posterior lip with, 1 pair simple appendages between 2 pairs bifid appendages ( Fig. 22 ).

Female (n=3): Body length 19.8 (15.7–27.8) mm, width 1120 (1050–1200), buccal capsule depth108, width 90. Deirids 589, nerve ring 601, excretory pore 680, from anterior end, oesophagus length 3713 (3410–3980). Vulva anterior to anus, 1697 (1400–1920) from the tip of tail. Ovejector with infundibulum 200, sphincter 200 and vestibule 268 about same length; vagina vera length 200 ( Fig. 23 ). Tail tapering, conical tip ( Figs 24, 25 ), length 1267 (990–1490). Eggs ellipsoidal, immature ( Fig. 26 )

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: 6.

Type specimens: Holotype male, allotype female ( MZB Na 643);

paratypes, 1 male and 3 females (MZBNa 644)

FIGURES 27–29. Scanning electron micrographs of Dorcopsinema and Paralabiostrongylus species. 27, D. longispicularis , cephalic end, en face view; 28, P. rajampatensis , anterior end of female, dorsal view showing cuticular frills; 29, D. longispicularis cephalic end of male 4th stage larva, en face view.

Etymology: This species is named after the island on which it was found.

Remarks: The cloacinine genus Paralabiostrongylus was erected by Smales (1982) for P. bi c ol l a r i s from the stomach of the forest wallaby D. muelleri and subsequently reported from the lesser forest wallaby Dorcopsulus vanheurni (see Smales, 1999). This monospecific genus is characterized by a poorly defined collar bearing cephalic papillae, 6 prominent fleshy lips or lip like processes with paired flaps, the two laterals bearing amphids and two short cuticular frills surrounding the oesophageal region between the cephalic collar and the deirids. The genus has been reported only from Papua New Guinea ( Smales, 1982, 1999).

Paralabiostrongylus rajampatensis sp. nov. belongs in the genus Paralabiostrongylus because of the characters of the anterior end; namely lip morphology and the presence of a cephalic collar, and cuticular frills. Paralabiostrongylus rajampatensis , a smaller worm than Paralabiostrongylus bicollaris the only other species in the genus, can be distinguished from P. bicollaris in having the deirids and excretory pore at about the same level, by the form of the dorsal ray, with lateral branches proximal to the bifurcation of the dorsal trunk, not distal as in P. bicollaris , the relatively longer spicule (1/10 body length compared with 1/16–1/20) with ala extending to the tip compared with ala not extending to the tip and in the form of the posterior lip of the genital cone (with 3 pairs of appendages compared with 2) ( Smales, 1982).

Both species are found in Dorcopsis muelleri but P aralabiostrongylus rajampatensis is found on the Raja Ampat Islands, Papua while P. bicollaris is found in the Middle Strickland Area, Papua New Guinea.

Figures

FIGURES 14 – 26. Paralabiostrongylus rajampatensis sp. nov. from Dorcopsis muelleri (Lesson, 1827). 14, Cephalic end female, en face view; 15, Cephalic end male, lateral view; 16, Anterior end of female, ventral view; 17, Bursa, lateral view; 18, Dorsal ray; 19, Spicule, distal end; 20, Spicule, proximal end; 21, Gubernaculum; 22, Genital cone, dorsal view; 23, Ovejector, lateral view; 24, Female tail, tip; 25, Posterior end female, lateral view; 26, Immature egg. Scale bars: 14, 15, 19, 20, 50 µm; 16, 400 µm; 17, 18, 23, 25, 100 µm; 21, 22, 24, 26, 25, 25 µm.