Pelecitus roemeri ( Linstow, 1905 ) Bartlett & Greiner, 1986

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 : 48-51

Pelecitus roemeri ( Linstow, 1905) Bartlett & Greiner, 1986

( Figs 85 , 89)

Filaria roemeri Linstow, 1905, pp. 356–8 , pl. 23, fig. 2, from Macropus antilopinus Australia.

Acanthocheilonema roemeri ( Linstow, 1905) Baylis, 1925, pp.114–115 ( Macropus giganteus ).

Dipetalonema roemeri ( Linstow, 1905) Yorke & Maplestone, 1926, p. 429 ; Johnston & Mawson 1938a, pp.111–112, figs. 8–13 ( Macropus robustus , M. fuliginosus (syn. M. melanops ), M. dorsalis , M. parryi , M. rufogriseus rufogriseus (syn. M. ruficollis ), Onychogalea fraenata ); Johnston & Mawson 1939, p. 309; Johnston & Mawson 1940, p. 365; Johnston & Mawson 1949, p. 69 ( Macropus agilis ).

Dirofilaria roemeri ( Linstow, 1905) Anderson, 1959, pp. 490–2 , figs. 44–7, 10–11, 13; Mackerras 1962, pp. 423–7, figs. 17–18 ( Macropus giganteus (syn. M. major ), M. rufus ); Spratt 1970, pp. 622–3; Spratt 1972b, pp. 193–200, figs. 1–12; Beveridge & Arundel 1979, p. 73; Beveridge et al. 1985, p.379;

Pelecitus roemeri ( Linstow, 1905) Bartlett & Greiner, 1986, p. 93 ; Beveridge et al. 1989, p. 278; Spratt et al. 1991, pp. 40, 43, 46, 48–50, 53, 55–56, 58–59, 61–62, 82, Beveridge et al. 1992, p. 367.

Filaria websteri Cobbold, 1879, p. 433 , from Macropus giganteus (syn. M. major )) Australia.

Dirofilaria websteri (Cobbold) Yorke & Maplestone, 1926, p. 395 .

Agamofilaria tabanicola Johnston & Bancroft, 1920, pp. 41–5 , figs. 1–8; Henry 1927, pp.197–8.

Type host. Macropus antilopinus (Marsupialia: Macropodidae ).

Other hosts. Macropus agilis , Macropus dorsalis , Macropus eugenii , Macropus fuliginosus , Macropus giganteus , Macropus parryi , Macropus robustus erubescens Sclater , Macropus robustus robustus , Macropus robustus woodwardi Thomas , Macropus rufogriseus banksianus , Onychogalea unguifera , Petrogale assimilis , Petrogale inornata , Petrogale persephone , Wallabia bicolor , Dendrolagus lumholtzi , (Marsupialia: Macropodidae ), Phascolarctos cinereus (Marsupialia: Phascolarctidae ).

Site in host: subcutis, especially in region of femuro-tibial joint, occasionally in fascia overlying shoulder, hips and abdomen. In Dendrolagus lumholtzi and Macropus parryi the site of predilection is the connective tissue between insertion of gastrocnemius and under biceps femoris.

Other material examined. (Numbers of males and females not tabulated)

From Dendrolagus lumholtzi: QLD : ( N 505, 541) Herberton; (( N 1721) Mt. Lewis nr Mossman; ( N 4073) Atherton; ( N 4451) Dirran Ck. nr Innisfail.

From Macropus agilis: QLD : ( N 1720) Inkerman Station; ( N 5218, 5219) Townsville.

From Macropus antilopinus: QLD : ( N 1039) Burlington Station.

From Macropus dorsalis: QLD : ( N 3156) Rockhampton.

From Macropus eugenii: ACT : (no N #) Tidbinbilla Nat. Res.

From Macropus fuliginosus: NSW : ( N 5260, 5261, 5262) Western Plains Zoo. VIC: ( N 5413) Brimpaen; ( N 1090) Moyhu. SA: ( N 899) Clare; ( N 1399, 1400) Sedan.

From Macropus giganteus: QLD : ( N 295) Gladstone; ( N 505) Inkerman Station; ( N 701, 702) Mingela; ( N 5256) Kelso; ( N 763) Kirrima nr. Ingham; ( N 5300) 5 km S Reid River; (no N #s) Durikai; 15 km W Warwick, Charleville, Telegraph Bore, Springsure, Adavale, Blackall, Richmond, Killeen. NSW: ( N 223) Dorrigo; (no N #s) Bathurst; ( N 561) Bondo State Forest; nr. Wee Jasper, Nadgee State Forest; Timbillica State Forest; Snowy Plains. ACT: Tidbinbilla Nat. Res. VIC: ( N 1812) Mitta Mitta, ( SAM 10547) Bonang.. TAS: ( N 892, 970) Icena.

From Macropus parryi: QLD : ( N 763, 830, 831) Kirrima nr. Ingham; ( N 4579) Kunwarara.

From Macropus robustus erubescens: QLD : (no N #s) Roma, Mitchell, Injune, Richmond, Springsure, Killeen, Charleville, Adavale. SA: ( N 1350) Melrose.

From Macropus robustus robustus: QLD : ( N 700) Charters Towers; (no N #) Durikai 15 km W Warwick

From Macropus rufogriseus banksianus :. QLD: (no N #) Durikai; 15 km W Warwick; NSW: ( N 732) Timbillica State Forest; ( N 650) Bondo State Forest; ( N 544, 785) Snowy Plains. ACT: (no N #) Tidbinbilla Nat. Res. VIC: ( N 5414) Wartook, ( SAM 10946) Mirranatwa.

From Macropus rufogriseus rufogriseus: TAS : ( N 969) Icena Station; ( N 4641) Sandy Cape.

From Macropus rufus: QLD : (no N #s) Roma, Mitchell, Telegraph Bore, Blackall Richmond, Springsure, Killeen, Charleville, Adavale.

From Onychogalea unguifera: QLD : ( N 1014, 1038) Wernadinga Station.

From Petrogale assimilis: QLD : ( N 2288) Myuna Station.

From Petrogale inornata: QLD : ( N 3197) Wandoo Station.

From Petrogale persephone: QLD : ( N 2658) Gloucester Island.

From Wallabia bicolor: NSW : (no N #) Nadgee State Forest; ( N 3075) Bondo State Forest; ( N 5390) Western Plains Zoo. VIC: ( N 18) Nariel; ( N 1811) Mitta Mitta; ( N 206) ( SAM 42720)Warby Ra.

From peritoneal cavity Phascolarctos cinereus: NSW : ( N 5189) Taree.

Exceptional material examined. ( Figs 86–87 , 89): From Macropus rufus: WA : 3♂, 5♀ ( N5481 ) 21 km N Roebourn, Pilbara ; 1♂ ( N5471 ), 22 km N Fortescue River Roadhouse, Pilbara.

From Macropus robustus erubescens: WA : 1♀, 1♀ anterior ( N5479 ), 45 km N Fortescue River Roadhouse, Pilbara.

From Macropus robustus woodwardi: WA : 1♀ ( N424 ) 20 km N Fitzroy crossing, Kimberley Province . Western Australia .

This series of specimens from large macropodoids in northern Western Australia posses a conundrum insofar as the lengths of spicules and the number and distribution of cloacal papillae in males are highly variable ( Table 5, Figs 86, 87 , 89). For example, measurements of males from one M. rufus ( N 5481) have the morphological features and mensuration of P. roemeri and a similar distribution of cloacal papillae with three rather than four or five pairs of large pedunculated pre-cloacal papillae. One specimen has longer left and right spicules, especially the filament of the left spicule and four pairs of large pedunculate pre-cloacal papillae. Another specimen has a markedly longer left spicule, particularly the filament, two pairs of large peduculate pre-cloacal papillae and a single pair of small papillae immediately pre-cloacal. The male from a second M. rufus ( N 5471) has very long left and right spicules, especially the filament of the left spicule and there are three large pedunculate pre-cloacal papillae on the right side and a single large pedunculate pre-cloacal papilla on the left side. More anterior position of the nerve ring. slightly longer oesophagi, more posterior position of the vulva and longer tails distinguished females from macropodoids in northern Western Australia from female P. roemeri from macropodoids in southeastern Queensland.( Table 5). Like P. roemeri , both sexes had lateral alae. Under the circumstances, until additional material is available from a range of large macropodoids in Western Australia I refer to this material as Pelecitus cf. roemeri .

Distribution and hosts. Pelecitus roemeri has a wide host range in the Macropodidae predominantly in eastern and central Australia but is not known from pademelons (Thylogale spp.), rufous and banded hare wallabies ( Lagorchestes spp. and Lagostrophus fasciatus (Péron & Johnston, 1857)) and the quokka ( Setonix brachyurus ), nor from members of the Potoroidae . Specific identity of the nematodes from large macropodoids in northern Western Australia remains problematic until further material is available for study.

Remarks. Pelecitus roemeri is transmitted by at least 12 species of tabanid fly ( Diptera : Tabanidae ) belonging to the genera Dasybasis, Lilaea (as Mesomyia ) and Tabanus ( Spratt 1972b, 1974a, b). This species is the only filarioid nematode of the many known from kangaroos, euros, wallabies, nail–tail wallabies and rock wallabies ( Macropodidae ) with sheathed microfilariae occurring in the blood of some but not all host species ( Spratt 1972a, 1974 b, 1975; Portas et al. 2005). Pelecitus roemeri is of particular relevance to the kangaroo game meat industry which has in place regulations concerning removal of large worms or the condemning of total carcasses being prepared for human consumption.

The record of a single female from the peritoneal cavity of a koala at Taree is considered an accidental infection, as are the records of male and female B. (B.) mundayi from Healesville Sanctuary, an unfertilised female of the same species from a wild koala at Coffs Harbour, and the record of Breinlia (Johnstonema) sp. from the heart of a koala. No males of any filarioid species have been recovered from koalas to date.

The detection of genetically distinct but morphologically similar (i.e. cryptic) species is now a well-recognised feature of parasitic nematodes of marsupials in Australia. ( Chilton et al. 1995, 1996, 2009).

Figures

FIGURES 85, 88. Pelecitus roemeri (Linstow 1905) Bartlett & Greiner, 1986 from Onychogalea unguifera, Queensland. 85, Caudal end male, latero-ventral view. 88, Left spicule, latero-ventral view. FIGURES 86–87, 89. Pelecitus cf roemeri from Macropus rufus Western Australia.86, Caudal end male, latero-ventral view. 87, Caudal end male, latero-ventral view. 89, Left spicule, latero-ventral view. Scale bars = 50 µm.