0020-7519/XX$3.00+000
Pergamon Press p/c Q 198XAuslralran Socrqfor ParaGtology
EIMERIA
SPP. (APICOMPLEXA :EIMERIIDAE) PARASITIC IN THE RAT-KANGAROOS HYPSIPR YMNODON MOSCHA TUS, POTOROUS TRIDACTYLUS, AEPYPRYMNUS RUFESCENS AND BETTONGIA GAIMARDI (MARSUPIALIA:POTOROIDAE) IAN
K. BARKER,*t$
MICHAEL
G. O’CALLAGHAN~
and IAN BEvERIDGEt
*Department of Pathology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada NlG 2Wl ?Central Veterinary Laboratories, Department of Agriculture, I.M.V.S., Frome Road, Adelaide, South Australia 5000, Australia (Received 23 December
1987; accepted 13 May 1988)
Abstract-BAaxaa I. K., O’CALLAGHAN M. G. and BEVERIDGE I. 1988. Eimeria spp. (Apicomplexa:Eimeriidae) parasitic in the rat-kangaroos Hypsiprymnodon moschatus, Potorous tridactylus, Aepyprymnus rufescens and Bettongia gaimardi (Marsupialia:Potoroidae). International Journal for Parasitology 18: 947-953. Nine new species of Eimeriu arc described from rat-kangaroos of the family Potoroidae. Five new species, E. hypsiptymodontis, E. tinarooensis, E. spratti, E. spearei and E. kairiensis, were found in the musky rat-kangaroo, Hypsiprymnodon moschatus, from the Atherton Tablelands, Queensland. Eimeria potoroi new species and E. mundayi new species occurred in the potoroo, Potorous tridactylus, from Tasmania. E. aepyprymni new species was found in a captive rufous bettong, Aepyprymnus rufescens, in South Australia but was absent in free-living bettongs originating from Queensland. Eimeria guimardi new species was the only coccidian found in the Tasmanian bettong, Bettongia gaimardi. INDEX KEY WORDS: Eimeria; new species; coccidia; Apicomplexa; marsupial; kangaroo; Hypsiptymnodon; potoroo; Potorous; bettong; Aepyprymnus; Bettongia.
INTRODUCTION
Potoroidae;
rat-
tionarily conservative of the two families comprising the Macropodoidea (Strahan, 1983).
No coccidia
have been described from the Potoroidae, or rat-kangaroos, though they have been characterized in a few species in the Macropodidae, including the Bennett’s or red-necked wallaby, Macropus rufogriseus, by Wenyon & Scott (1925) and Zwart & Strik (1964); the grey kangaroos, identified as M. gigunteus by Yakimoff & Matschoulsky (1936) or as M. cunguru by Mykytowycz (1964) prior to the clarification of the status of M. gigunteus and M.&liginosus; the red kangaroo M. rufus by Prasad (1960) and Mykytowycz (1964); and the rock wallabies Petrogule spp. by Barker, O’Callaghan, Beveridge & Close (1988). As part of a systematic study of the coccidia parasitizing members of the Macropodoidea, we describe here a number of species of Eimeria encountered in the musky rat-kangaroo Hypsiprymnodon moschatus, the long-nosed potoroo Potorous tridactylus, the rufous bettong Aepyprymnus rufestens, and the Tasmanian bettong Bettongia gaimardi, representatives of the Potoroidae, the more evolu-
MATERIALS
AND METHODS
Faeces were examined from five H. moschatus collected on the Atherton Tableland, north Queensland; from three P. tridactylus collected in the vicinity of Launceston, Tasmania; from five A. rufescens, four from the vicinity of Townsville, Queensland and one from the zoo in Adelaide, South Australia; and from 13 B. gaimardi from Launceston, Tasmania. Animals were collected in live traps, by shooting, or as road kills, with the exception of the captive zoo animal, which was a necropsy accession. Faeces were placed in 2.5% potassium dichromate; oocysts sporulated at room temperature and were stored in 4’C. Since faeces had spent time in transit, sporulation time could not be determined. Oocysts were concentrated by flotation in sucrose solution (SG 1.30) and were examined under oil immersion with a 100 X Plan Achromat lens on an Olympus BH microscope, using a Nomarski differential interference contrast system. Oocysts of each type were measured as they were encountered, using a calibrated eyepiece graticule. Measurements of a minimum of 15 unselected oocysts of each species were made, and are given in microns in Table 1, or in the text as the mean k S.D. (range). RESULTS
*To whom correspondence should be addressed at: Department of Pathology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada NlG 2Wl.
Oocysts of five new species of Eimeria were present in the faeces of H. moschatus, two in P. tri947
948
I. K. BARK~K, M. G. O’CALLAGHAN and I. BEVERIDG~
dactylus, one in A. rufescens and one in LI. gaimardi The measurements of oocysts of the species infecting H. moschatus are summarized in Table 1. Descriptions of the species found in each host, based on oocysts found in faeces, follow; endogenous stages of all species are unknown. New species of Eimeria from Hypsiprymnodon moschatus, the musky rat-kangaroo, follow:
Eimeria hypsiprymnodontis new species (Figs. 1, 2) Description. Oocyst bluntly ellipsoidal; measurements Table 1; double oocyst wall; outer layer with irregular rough surface, tan colour, 2.4-3.2 pm thick, occasionally thinner and collapsing in at one pole in sucrose, but no clear micropyle; inner clear, 0.4 iurn thick; polar granule 1.2 pm diameter; four ellipsoidal sporocysts more pointed toward end with Stieda body, which is sometimes asymmetrically applied; lenticulate substieda body, 2.4 pm deep X 3.2 pm across; two large recurved sporozoites with finely granular cytoplasm, filling sporocyst; large refractile globule 7.2 pm X 4.8 pm; sporocyst residuum cluster of 1 O-20 granules 1.6 ,Hm in diameter, loosely aggregated about equator of sporocyst. Diagnosis. Based on combination of dimensions of oocyst and sporocyst, with suite of morphologic characters described. The large oocyst size and thick, rough outer oocyst wall are characteristic, among coccidia of Hypsiplymnodon. Host. Hypsiplymnodon moschatus, Atherton Tableland, Queensland. Prevalence. Rarely encountered in three/five animals.
Eimeria tinarooensis new species (Figs. 3,4) Description. Oocyst subspherical to bluntly ellipsoidal; measurements Table 1; double oocyst wall; outer layer 2.0-2.4 ,um thick, thinning to 1.6 pm at the poles, tan colour, radial striations, with finely mamillate surface; polar granule 1.6 pm diameter; four ellipsoidal sporocysts, more pointed at end with small, clear knob-like Stieda body; clear substieda body; two sporozoites recurved, with finely granular cytoplasm, filling sporocyst; refractile globule 4.8 X 3.2 pm; sporocyst residuum a loose aggregate of granules 1.6 iurn in diameter scattered about equator of sporocyst. Diagnosis. This species is differentiated from E. hypsiprymnodontis by its more irregular shape, more regular oocyst surface, and smaller sporocyst. Host. Hypsiprymnodon moschatus , Atherton Tableland, Queensland. Prevalence. Common in four/five animals. Comment. The species name is derived from the type locality, Tinaroo, on the Atherton Tableland, Queensland.
Eimeria spratti new species (Figs. 1, 5) Description. Oocyst subspherical; measurements Table 1; double oocyst wall; outer layer clear, light tan, comprised of flattened granules up to 3.2 ,LL~ in diameter and about 1.6 pm thick, giving the surface a cobblestone-like appearance; inner layer clear, 0.4 pm thick; polar granule 2.4 pm diameter; four sporocysts, ellipsoidal, more pointed at end with inconspicuous Stieda body; clear substieda body; two sporozoites filling sporocyst; large refractile globule 6.4 pm X 3.2 pm; sporocyst residuum mass of granules 1.6 pm diameter, dispersed about equator of sporocyst. Diagnosis. Based on size of oocyst and sporocyst, and suite of morphologic characteristics described, particularly its unusual outer oocyst wall. Host. Hypsiprymnodon moschatus, Atherton Tableland, Queensland. Prevalence. Common in five/five animals. Comment. This species is named in recognition of Dr D. M. Spratt, C.S.I.R.O. Division of Ecology and Wildlife Research, Canberra.
Eimeria spearei new species (Figs. 1,6) Description. Oocyst spherical to subspherical; measurements Table 1; double oocyst wall; outer layer 0.8 ,um thick, light tan, clear, with a finely pebbled surface; inner layer clear, 0.4 ,LL m thick; polar granule present; four sporocysts, ellipsoidal with small knob-like Stieda body; small lenticular substieda body; two sporozoites with finely granular cytoplasm, filling sporocyst; two refractile globules, the larger 4.8 pm X 2.4 pm, the smaller 2.4 ,LL~ in diameter; sporocyst residuum 4.8 ,LL~ diameter aggregate of granules about 1.6 pm in diameter, at equator of sporocyst. Diagnosis. Based on oocyst and sporocyst size, and suite of morphologic characteristics described. Host. Hypsiprymnodon moschatus, Atherton Tableland, Queensland. Prevalence. Very common in five/five animals. Comment. This species was the most common in the animals examined. It is named in recognition of Dr Richard Speare, Postgraduate School of Tropical Veterinary Science, James Cook University, Townsville, Queensland.
Eimetia kairiensis new species (Fig. 7) Description. Oocyst spherical to subspherical; measurements Table 1; double oocyst wall; outer layer 0.6 pm, yellow hue, finely mamillate surface; inner clear, colourless; polar granule present; four ellipsoidal sporocysts with knob-like Stieda body; two sporozoites filling sporocyst; elongate refractile globule 3.2 pm X 1.6 pm; sporocyst residuum a few granules 0.8 pm in diameter scattered at equator of sporocyst.
E. E. E. E. E.
hypsiprymnodontis tinarooensis spratti spearei kuiriensis
Species 15 22 30 47 44
n 28.6 26.0 21.3 16.9 13,4
i 1.62 1.15 1.51 1.03 I,06
S.D‘ Range
Oocyst
22.7 23.8 19.4 16.3 12.9
x: 0.99 0.97 1.81 1.05 1.21
SD.
Width
20.8-24.0 21.6-26.4 16.0-23.2 13.6-18.4
[email protected]
Range 17.0 12.3 13.1 10.4 8.2
f
0.54 0.77 1.10 0.79 0.66
S.D.
Range 16.0-17.6 11.2-14.4 11.2-15.2 8.0-l 2.0 6.4-9.6
Length
8.3 7.9 7.6 6.4 5.2
x
AND E.
SpKXjBt
OF Eimeria hypsiprymnodontis, E. tlnarooensis, E. spearei Hypsiprymnodon moschatus
SPOROCYSTS
25.6-32.0 24.0-28.0 18.4-24.0 15.2-20.0 11.2-15.2
Length
TABLE ~-DIMENSIONS (pm) OP THE OOCYSTSAND
0.41 0.31 0.65 0.50 0.60
SD.
Width
8.0-8.8 7.2-8.4 6.0-8.8 5.2-7.2 4.0-6.4
Range
kairiensis FROM
1. K. BARKER,
FIGS.
l-7.
Oocysts
of various
FIG. I. E. hypsiprynnodontis
Eimeria
M. G.
O’&I.LAGHAN
and I. B~VERIDGE
species from the musky rat-kangaroo, bar = 10 ,~m; all figures to same scale.
(A), E. sprat/i (B) and E. spearei (C), showing oocysts in H. moschatus.
~~p.~ip~~~odon
profiles of the three types of walls of coccidial
FIG. 2. E. hy~s~~~tnnctrlonris,showingsporocyst. FIG. 3. E. tinarooensis FIG. 4. E. tinarooensis, sporocyst
and texture of outer aocyst wall.
FIG. 5. E. spratti. FIG. 6. E. spearei. FIG. 7. E. kairiensis.
moschoius. Scale
Coccidia of rat-kangaroos Diagnosis. Based on oocyst and sporocyst dimensions, and suite of mo~hoiogic characteristics described. This species has the smallest oocyst found in H. moschatus . Host. Hypsiprymnodon moschatus , Atherton Tableland, Queensland. Prevalence. Colon in five/five animals. Comment. It is named for the town of Kairi, on the Atherton Tableland, which has an architecturally unique pub.
New species of E~mer~a from Potorous tr~da~~lus, the long-nosed potoroo, follow: Eimeriapotoroi new species (Fig. 8) Description. Oocyst ovoid to pyriform, 20 measured 26.2 & 1.67pm (24.0-29.6 pm) X 18.5 f 1.25 ,um (16.8-22.4 pm); double oocyst wall, micropyle present, 4.0 pm across; outer layer 1.Opm thick, tan, clear, radially striated, with a mamillate surface; inner layer clear, 0.4 pm thick; oocyst residuum aggregate of two-six granules 1.6 ,~rn in diameter; four ellipsoidal sporocysts 11.9 + 0.70 firn (10.8-13.6 pm) X 7.6 i 0.76 pm (6.4~8.8pm) with pro~berant Stieda body; clear lenticulate substieda body; two curved sporozoites, not filling sporocyst; refract& globule 3.2 pm diameter; sporocyst residuum loose aggregate of granules up to 2.0 iurn in diameter scattered about equator of sporocyst. Diagnosis. Based on oocyst and sporocyst dimensions, and suite of morphologic characteristics described. Host. Potorous tr~dac~~us, near Launceston, Tasmania. Eimeria mundayi new species (Figs. 9, 10) Description. Oocysts spherical to subspherical; 40 measured 16.9 & 1.87 pm (13.6-20.8 pm) X 16.2 f 1.56 ,~rn (13.6-19.2 pm); double oocyst wall; outer wall tan, clear, 1.O pm thick, with mamillate surface; inner layer clear, 0.4 pm thick, polar granule present; four ellipsoidal to ovoid sporocysts 9.7 i: 1.08 pm (8.0-12.0 pm) X 6.2 k 0.75 flrn (4.8-8.0 pm) with Stieda body and substieda body; two curved sporozoites, not filling sporocyst; refractile globule 2.44.0 pm diameter; sporocyst residuum a few scattered granules 0.8-1.6 pm diameter at equator of sporocyst. Diagnosis. Based on oocyst and sporocyst dimensions, and suite of morphologic characteristics described. This species has a wide range in size of both oocysts and sporocysts, and a positive correlation between length of oocyst and sporocyst. Host. Potorous tridactylus, near Launceston, Tasmania. Comment. This species is named in recognition of Dr Barry L. Munday, formerly director of the Mt.
Pleasant Laboratories, Tasmanian ture, Launceston, Tasmania.
951 Dept. of Agricul-
Species of Eimeria in Aepyppypnnus rufescens, the rufous bettong, follow. Eimeria ~epyp~~i new species (Fig. 11) Description. Oocyst ellipsoidal, 3.5 measured 36.7 f 2.76 pm (32.0-42.8 pm> X 21.9 f 1.48 pm (18.4-25.2 ,Um); double oocyst wall; outer layer clear, colourless, smooth, 1.5 pm thick; inner clear, 0.5 pm thick; no polar granule; four ellipsoidal sporocysts, 15.8 f 0.87 pm (13.6-17.6 pm) X 9.5 & 0.67 pm (7.8-10.8 pm); Stieda body and lenticulate substieda body present; two sporozoites with finely granular cytoplasm, not filling sporocyst; refractile globule 5.6 ,Um diameter; sporocyst residuum compact finely granular mass about 5.6 pm diameter, at equator of sporocyst. Diagnosis. Based on oocyst and sporocyst dimensions and suite of morphologic characters described. Host. Aepyprymnus rufescens, Adelaide Zoo, Adelaide, S.A. Prevalence. Common in one/five animals, a captive which died for unrelated reasons in the Adelaide Zoo. Four A. rufescens from north Queensland had no oocysts in faeces. Species of Eimeria in Bettongia gaimardi, Tasmanian bettong, follow:
the
Eimeria gaimardi new species (Figs. 12, 13) Description. Oocyst ovoid to pyriform, 15 measured 34.6 i- 1.88 ,um (32.0-39.2 pm) X 24.3 + 1.78 ym (20.8-26.4 pm); double oocyst wall, outer layer colourless, mamillate 1.2 pm thick; outer layer thins at apex but no clear micropyle, inner layer clear 0.4 pm thick; four ellipsoidal sporocysts 15.0 & O.70pm (13.6-16.0 pm) X 9.6 f 0.40 pm (9.010.4 pm); Stieda body and lenticulate substieda present; two sporozoites vith finely granular cytoplasm not filling sporocyst; two refractile globules in each sporozoite, the larger 6.4 ,Um in diameter and the smaller 2.4 pm in diameter; sporocyst residuum loose aggregate of granules at equator of sporocyst. Diagnosis. Based on oocyst and sporocyst dimensions in combination with suite of morphologic characteristics described. Host. Bettongia gaimardi, Launceston, Tasmania. Prevalence. Common in five/l 3 animals. DISCUSSI0N Coccidia of the genus Eimeria are typically highly host-specific, usually being restricted to no more than a few closely related species, or a single genus (Joyner, 1982; Long 81 Joyner, 1984). Some coccidia which parasitize sheep and goats seem to have been conservative morphologically as they evolved, host specificity separating pairs of Eimeria spp. with similar
952
FIGS. 8-10.
I. K.
BARKER,M. G. O’CALLAGHAN and 1. BEVERIDCE
Oocysts of Eimeria spp. from the long-nosed potoroo, Potorous tridacrylus. Scale bar = 10 pm; all figures to same scale. FIG. 8. E. poloroi. FIG. 9. E. mundqi.
M~illate surface of outer oocyst wall of E. mundayi, also characteristic of E. potorui. FIG. il. Oocyst of E. crepyprymni from the rufous bettong, Aepypvymnus rufescens. FIG. 12. Oocyst of E. guimardi from the Tasmanian bettong, Be&mgiagaimardi.
FIG. 10.
Ftc. 13. Mamillate surface of outer oocyst wall of E. guimardi.
oocysts (McDougaId, 1979; Savin, Dincer & Milli, 1980), presumably descended from a common ancestor. If this trait is general, the coccidia of macropodoid marsupials may have trailed behind their hosts in terms of morphologic divergence, while radiating with them. Based on this premise, we began a study of the Eimeria spp. parasitizing members of the Macropodoidea, seeking, among the oocysts, similarities which might serve as markers of phylogenetic relationships of the hosts. Among the coccidia found in the complex of species comprising the rock wallaby genus Petrogale, individual species, or groups of species of Eimeria, appear to be limited to hosts of one or another of three species groups, defined on the basis of cytogenetic and isoenzyme studies (Barker et
Eirrteria parasitizing the three genera of the Potoroidae examined. This is not surprising, since, superimposed upon the generic differences, two subfamilies, the Potoroinae and the Hypsiprymnodontinae, are represented. Unfortunately, oocysts could not be obtained from sufficient animals, of more than one species within the same genus, to indicate whether the hypothesis might hold up when tested among the Potoroinae. Within the monospecific genus Hypsiprymnodon, the group of species of Eimeria is relatively large, and homogeneous in terms of such characteristics as size and shape of oocyst and sporocyst, type of oocyst wall, and presence of Stieda body and substieda body.
al., 1988).
A group of species of such homogeneity may be the result of radiation, within this host, of one or two lineages of Eimeria isolated by host specificity.
The results of the small survey reported here suggest that, when compared by host, no strong morphologic similarities exist among the species of
Acknowledgements-We thank Drs Barry Munday, David Obendorf, Richard Speare and David Spratt for assistance in
Coccidia of rat-kangaroos coltecting specimens; animals were taken under permits from the appropriate fauna authorities. Liz Moore helped in the laboratory. Photographic processing was done by Mark Fitzgerald. This work was supported in part by an International Collaborative Research Gram from the Natural Sciences and Engineering Research Council of Canada to I. K. Barker. REFERENCES BARKERI. K., O’CALLAGHAN M. G., BEVERIDGE I. & CLOSE R. L. 1988. The host-parasite associations of Eimeria
spp. {Apicomplexa:Eimeriidae)
in rock wallabies,
gale spp. International Journalfor
Pefro-
Parasitology 18: 353-
363. JOYNERL. P. 1982. Host and site specificity. In: The Sio1ogy of the Coccidia (Edited bv LONG P. L.), PP. 35-62. , L.
University Park Press, Baltimore. LONGP. L. & JOYNERL. P. 1984. Probiems in the identifiction of species of Eimeria Journal of Protozooiogy 3 1: 535-541. MCDOUGALDL. R. 1979. Attempted cross-tr~s~ssion of coccidia between sheep and ‘goats and description of Eimeria ovinoidaiis sp. n. Journal of Protozoology 26: 109-l 13.
953
MYKYTOWYCZ R. 1964. Coccidia in wild populations of the red kangaroo Meguteia rufu (Desmarest) and the grey kangaroo Macropus cangaru (Miiller). Parasitology 54: 105-l 15. PRASADH. 1960. A new species of coccidia from the red kangaroo Macropw rufus Mamm. Zeitschrif fiir Parasitenkundc 20: 385-389.
SAVINF., DI~JCERS. & MILLI U. 1980. The life cycle and pathogenicity of Eimeria arfoirzgi (Marotef, 1905) Martin, 1909, in Angora kids and an attempt at its transmission to Iambs. Zentralblatt fiir ~eterinurmed~z~~ (B) 27: 392-397.
STRAHANR. 1983. The Complete Book of Awtralian Mammals. DD. 207-223. Angus and Robertson. Svdnev. WENYON C.‘k. & SCOTT H.-H. 1925. Exhibitions ‘of sections of the small intestine of a Bennett’s wallaby (Macropus bennetti) containing various parasites. Transactions of the Royal Society for Tropical Medicine and Hygiene 19: 7-8.
YAKIMOFF W. L. & MATXHOULSKY S. N. 1936,Coccidiosis in the kangaroo. ~0~1~~~~ ofParasito~o~ 22: 5 14-S 1.5. ZWART P. & STRIKW. J. 1964. Globidiosis in a Bennett’s wallaby. Tijdschriji voor Diergeneeskunde 89 (Suppl. 1): 138-143.
