Breinlia (Breinlia) dorcopsis, 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 : 14

Breinlia (Breinlia) dorcopsis sp. nov.

Figs. (21–28)

Type host. Dorcopsis hageni Heller (Marsupialia: Macropodidae ).

Other hosts. Dorcopsis luctuosa (D’Albertis) .

Site in host. Peritoneal cavity.

Material examined. Holotype: ♂, from Dorcopsis hageni Heller, Usino, Madang, Papua New Guinea (5 0 31’S, 145 0 22’E), coll: T. Reardon, 15.v.1987, AHC 45849; allotype: ♀ anterior and posterior fragments, AHC 45850; paratypes: 1♂, AHC 45851; 1♂ posterior end, QM G232514 1♀ fragments, QM 232515.

Other material examined. From Dorcopsis luctuosa (D’Albertis) : PNG: 1♀ ( N3313 ). unfertilised, originally from Rigo area (9 0 48’S, 147 0 33’E), died in captivity Port Moresby .

Etymology. The species is named after the host genus.

Differential diagnosis. Breinlia (Breinlia) dorcopsis is distinguished from all other species of the subgenus by having the largest RS/LS ratio, 1:3.6, with the exception of B. (B.) spelaea , 1:4.0–1:4.2. However, it is readily distinguished from the latter by shorter right and especially left spicules, much shorter filament of left spicule, generally shorter tail in males, more anterior position of the vulva and longer tail in females.

Description. General: Moderately long nematodes with attenuated anterior and posterior extremities. Oral opening small, round, bounded by delicate membrane. Cephalic extremity not determined in en face view. Four pairs of submedian papillae arranged in outer circle of four large and inner circle of four smaller papillae. Amphids large, lateral, opening at level of outer circle 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 5.6 mm anterior to cloaca and terminating approximately 1.1 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 paratypes). BL 52, 55 mm. MW 292, 275, 292. NR 291, 292. EP 408. MO 301, 371, GO 1 988, 1570. LS 600, 613, 640; Cal 208, 208,176, Lam 104, 94, 94, Fil 288, 291, 270. RS 177, 160, 146, with spatulate distal extremity. Posterior end generally tightly coiled. Gub 40, 37. Cloacal papillae 12–13 in number, three or four pairs pre–cloacal and one or two pairs and one to three median single papillae post–cloaca. T 477, 519, 610, terminating in two pairs of latero-ventral papillae.

Female: (Allotype measurements presented first, in italics, followed by paratype fragments). BL longest fragment 140. MW 435, 505. NR 222. EP not observed. MO 398; GO 1802. V 3315 from cephalic extremity. T 1193, 1378, with two small terminal papillae.

Microfilariae: (5 specimens from uterus). BL 185 (183–187). MW 6 (5–6). Tail long, filamentous, nuclear column terminating in 5–6 single, elongate nuclei. LNT 28 (26–29). Microfilaria unsheathed. Site in host unknown.

Distribution and hosts. Breinlia (B.) dorcopsis is known only from one individual in each of two species of scrub wallaby belonging to the genus Dorcopsis in Papua New Guinea, a genus which does not occur in Australia.

Remarks. The characteristics of B. (B.) dorcopsis distinguishing it from all other species in the subgenus and from B. (B.) spelaea are noted under the differential diagnosis provided. The new species is distinguished from B. (B.) dendrolagi which occurs in the peritoneal cavity of tree kangaroos, Dendrolagus spp. , in Australia and New Guinea by the much longer spicules, especially the left spicule, refractile cuticular bosses in males not arranged in transverse bands and the more anterior position of the vulva in females.