Breinlia (Breinlia) oweni, Spratt, 2011

Spratt, David M., 2011, New records of filarioid nematodes (Nematoda: Filarioidea) parasitic in Australasian monotremes, marsupials and murids, with descriptions of nine new species 2860, Zootaxa 2860 (1), pp. 1-61 : 21-23

Breinlia (Breinlia) oweni sp. nov.

( Figs 38–47 )

Type host. Dactylopsila trivirgata Gray (Marsupialia: Petauridae ).

Site in host. Peritoneal cavity.

Material examined. Holotype: ♂, from Dactylopsila trivirgata, Balamuk , Western Province, Papua New Guinea (08 0 55’S, 141 0 17’E), coll: I. Owen, December,1988, AHC 45861, allotype: ♀, AHC 45862; paratypes: 2♂, AHC 45863; 3♂, QM G232521; 1♀, 4♀ anterior and posterior fragments, AHC 45864, 1♀, 1♀ anterior and posterior fragments QM G232520; 1♂ broken, ♂ and ♀ fragments ( N3069 ).

Etymology. The species is named after Mr. Ifor Owen who collected the material and who has been, for several decades, a diligent collector of parasites from wildlife in Papua New Guinea.

Differential diagnosis. Breinlia (Breinlia) oweni is most similar to B. (B.) mackerrasae from short–nosed bandicoots in eastern Australia and B. (B.) presidentei from murid rodents in northwest Western Australia. It is distinguished from the former by much shorter males and females, shorter right spicule, much longer filament of left spicule (0.21 vs 0.13 as measured from Fig. 2 of Walker and MacMillan, 1974), fewer post–cloacal papillae and none located close to posterior extremity, shorter muscular oesophagus and tail in males, more anterior position of vulva, much shorter tail and shorter muscular and glandular oesophagus in females. It is distinguished from B. (B.) presidentei by slightly shorter males and much shorter females, presence of rectangular rather than square peribuccal fields in apical view of cephalic end, shorter right spicule and muscular oesophagus in males and much shorter tail in females, the tail tip in both sexes terminating in a pair of latero–ventral papillae and a median papilla.

Description. General: Moderately long nematodes with posterior extremity more attenuated than anterior. Oral opening small, round, bounded by delicate membrane. Four pairs of submedian papillae arranged in outer circle of four large and inner circle of four smaller papillae. Rectanglar, cuticular, peribuccal field present, joining bases of papillae of inner circle. Second, less conspicuous, rectangular peribuccal field present, formed by slight elevation of cuticle joining bases of papillae of outer circle. Internolateral papillae absent. Amphids large, lateral, opening at level between two circles of papillae. Buccal capsule small, narrow, with small, refractile, ring at its base. Oesophagus divided into thin muscular and thicker glandular regions. Intestine broad. Cuticle with transverse striations especially pronounced in females, longitudinal, refractile cuticular bosses present on ventral surface of male only, commencing approximately 9 mm anterior to cloaca and terminating approximately 1 mm anterior to cloaca, increasing in density posteriorly. Lateral cords with 3 columns of nuclei, a narrow, central column of widely–spaced, elliptical nuclei with prominent nucleoli and wider, peripheral columns of closely–spaced, elliptical nuclei with prominent nucleoli. Spicules unequal, dissimilar, sclerotised. Gubernaculum present. Lateral alae and caudal alae absent. Phasmids and deirids not observed.

Male: (Holotype measurements presented first in italics, followed by 6 paratypes). BL 44, 47 (42–50) mm. MW 265, 255 (239–292). NR 186, 207 (186–239). EP not observed. MO 413, 331 (212–385). GO 1246, 1034 (848–1139). LS 479, 475 (447–507); Cal 208, 200 (177–218), Lam 73, 74 (62–83), Fil 198, 202 (187–208). RS 166, 155 (146–507) with spatulate distal extremity. Posterior end generally tightly coiled. Gub 30, 30 (30–33). Cloacal papillae 11–13 in number, variable in disposition, generally three pairs pre–cloacal, one pair ad–cloacal, one pair immediately post–cloacal and one to three single median papillae ranging 52–212 posterior to cloaca. T 493, 428 (395–477), terminating in single pair small latero-ventral papillae and single smaller median papilla.

Female: (Allotype measurements presented first, in italics, followed by 2 complete paratypes and 5 large paratype fragments). BL 90, 95 (82–107). MW 451, 455 (449–477). NR 228, 209 (196–228). EP not observed in allotype, 350 (345–355). MO 322; 411 (345–451). GO 1378, 1196 (928–1457). V 3318, 3148 (2095–4487). T 742, 553 (436–610), terminating in two small latero-ventral papillae and a single smaller median papilla.

Microfilariae: (5 specimens from uterus). BL 212 (208–214). MW 5 (4–5). Tail long, filamentous, nuclear column terminating in 5–6 single, elongate nuclei. LNT 23(21–24). Microfilaria unsheathed. Site in host unknown.

Distribution and hosts. Breinlia (B.) oweni is known from a single Dactylopsila trivirgata in Papua New Guinea. Although the striped possum occurs also in northern Australia, filarioid nematodes have not been reported from it ( Spratt et al., 1991) and filarioids have not been seen in fourteen animals examined from north Queensland.

Remarks. Breinlia (B.) oweni is most similar to B. (B.) mackerrasae and B. (B.) presidentei and distinguished from them under the differential diagnosis provided.

Figures

FIGURES 38–47. Breinlia (Breinlia) oweni sp. nov. 38, Cephalic end female, apical view. 39, Cephalic end female, dorsal view. 40, Anterior end female, lateral view. 41, Posterior end male, lateral view. 42, Caudal end male, ventral view. 43, Posterior end female, lateral view. 44, Oesophago-intestinal junction female, lateral view. 45, Vulva, vagina and intestine female, lateral view. 46, Cloacal papillae male, ventral view. 47, Cuticular bosses male, latero-ventral view. Scale bars: Figs 38, 39, 41, 42, 46, 47 = 50 µm, Figs 40, 43–45 = 100 µm.

FIGURES 1–6. Breinlia (Breinlia) beveridgei sp. nov. 1, Cephalic end, lateral view. 2, Oesophago-intestinal junction, lateral view. 3, Anterior extremity, male, lateral view. 4, Right spicule and gubernaculum, lateroventral view. 5, Posterior end male, lateral view. 6, Left spicule, lateral view. Scale bars: Fig. 1 = 20 µm, Figs. 2–5 = 50 µm, Fig. 6 = 100 µm.