A new species of Isospora (Apicomplexa: Eimeriidae) from Carolina chickadee (Passeriformes: Paridae), from Oklahoma, USA.

The Carolina chickadee, Poecile carolinensis Audubon is a relatively small songbird belonging to the tit and chickadee family Paridae. Feces from three P. carolinensis from Polk County, Arkansas, USA, and a single P. carolinensis in McCurtain County, Oklahoma, USA, were collected and examined for coccidia; the latter bird was found to be passing a new species of Isospora. Oöcysts of Isospora oklahomaensis n. sp. are subspheroidal to ovoidal with a smooth to slightly-pitted bi-layered wall, measure (L × W) 32.1 × 28.3 µm, and have a length/width (L/W) ratio of 1.1; a micropyle and oöcyst residuum were absent but a bilobed and refractile polar granule is present. Sporocysts are ellipsoidal and measure 18.4 × 11.8 µm, L/W 1.6; a prominent Stieda body is present as well as a distinct sub-Stieda body. The sporocyst residuum is composed of an irregular mass of granules lying between and dispersed among the sporozoites. This is the first coccidian described from the Carolina chickadee and, most importantly, only the second described from a member of the Paridae, worldwide.

A new eimerian (Apicomplexa: Eimeriidae) from southern short-tailed shrews, Blarina carolinensis (Bachman) (Soricimorpha: Soricidae: Soricinae) from southeastern Oklahoma, USA.

A new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) is described from faecal samples of two of three southern short-tailed shrews, Blarina carolinensis (Bachman) (Soricidae) from southeastern Oklahoma, USA. Oöcysts of Eimeria tkachi n. sp. are subspheroidal to ovoidal with a rough-pitted, tan colored, bi-layered wall, measure 16.5 × 15.2 µm, and have a length/width (L/W) ratio of 1.1; both micropyle and oöcyst residuum are absent, but polar granule(s) are present. Sporocysts are ovoidal, 9.5 × 6.5 µm, L/W 1.4; a distinct button-like Stieda body is present, but the sub-Stieda and para-Stieda bodies are absent and the sporocyst residuum is composed of large globules distributed throughout the sporocyst. Sporozoites have a spheroidal anterior refractile body, a subspheroidal posterior refractile body, and one centrally-located nucleus. This is the smallest eimerian described thus far from the Soricidae, the initial description of a coccidian from B. carolinensis, and the first from any shrew from Oklahoma.

A new eimerian (Apicomplexa: Eimeriidae), from ornate box turtle, Terrapene ornata (Agassiz) (Testudines: Emydidae) from northwest Arkansas, USA.

A new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) collected from an ornate box turtle, Terrapene ornata (Agassiz) from Arkansas, USA, is described. Oöcysts of Eimeria doddi n. sp. are ovoidal to ellipsoidal with a smooth, light to darker brown, bi-layered wall, measure 21.1 × 14.0 µm, and have a length/width (L/W) ratio of 1.5; both micropyle and oöcyst residuum are absent, but a polar granule is present. Sporocysts are ellipsoidal, 9.9 × 6.1 µm, L/W 1.6; the Stieda body is present, but the sub-Stieda and para-Stieda bodies are absent and the sporocyst residuum is composed of small granules in a cluster. Sporozoites have a spheroidal anterior refractile body, a subspheroidal posterior refractile body, and one centrally-located nucleus. This is the third description of an eimerian from the turtle genus Terrapene Merrem and the second from T. ornata. In addition, we report Eimeria ornata McAllister & Upton, 1989 from T. ornata from Texas.

A new coccidian (Apicomplexa: Eimeriidae), from midland brown snake, Storeria dekayi wrightorum Trapido (Ophidia: Colubridae) from Arkansas, USA.

A new species of coccidian (Protista: Apicomplexa: Eimeriidae) collected from the faeces of a midland brown snake Storeria dekayi wrightorum Trapido (Ophidia: Colubridae) in Arkansas, USA, is described. Oöcysts of Isospora holbrooki n. sp. are subspherical to ovoidal with a smooth, colourless, bi-layered wall, measure on average 27.1 × 24.0 µm, and have a length/width (L/W) ratio of 1.1; both micropyle and oöcyst residuum are absent, but a polar granule is present. Sporocysts are ovoidal, 14.8 × 10.0 µm on average (L/W 1.5); the Stieda body is nipple-like, the sub-Stieda body is ellipsoidal and the sporocyst residuum is composed of coarse granules in a cluster. Sporozoites have a spheroidal anterior refractile body, a subspheroidal posterior refractile body, and one centrally-located nucleus. This is the first description of an isosporan from the snake genus Storeria Baird & Girard as well as the largest oöcysts and sporocysts of any previous snake isosporan to date.

A new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) from the brown anole Anolis sagrei Duméril & Bibron (Sauria: Dactyloidae) in Florida, USA.

During July 2014, 14 brown anoles, Anolis sagrei Duméril & Bibron were collected from Orange County, Florida, USA, and their faeces examined for coccidian parasites. One (7%) lizard harboured an eimerian that we describe here as new. Oöcysts of Eimeria garmani n. sp. were ellipsoidal with a uni-layered wall and measured 19.3 × 12.5 µm, with a length/width ratio of 1.5. A micropyle and oöcyst residuum were absent but 1-2 polar granule(s) were present. Sporocysts were subspheroidal, 6.8 × 6.3 µm, with a length/width ratio of 1.1. Stieda, sub-Stieda and para-Stieda bodies were absent. A sporocyst residuum was present as dispersed granules. Endogenous stages were observed within the small intestine. This is the first coccidian reported from the brown anole and the third eimerian reported from anoles in the United States.

A New Host for Caryospora lampropeltis (Apicomplexa: Eimeriidae) from the Eastern Hognose Snake, Heterodon platirhinos (Ophidia: Colubroidea: Dipsadinae), from Arkansas, U.S.A., with a Summary of Hosts of This Coccidian.

Between May 2012 and July 2013, four eastern hognose snakes (Heterodon platirhinos) were collected from Arkansas (n = 2) and Oklahoma (n = 2), U.S.A., and examined for coccidians. A single H. platirhinos from Arkansas was found to be passing oocysts of Caryospora lampropeltis Anderson, Duszynski, and Marquardt. Oocysts of C. lampropeltis were spheroidal to slightly subspheroidal with a rough, colourless, bi-layered wall, measure 23.5 × 22.8 µm, and have a length/width (L/W) ratio of 1.0; both micropyle and oocyst residuum were absent, but a prominent polar granule was present. Sporocysts are ovoidal, 16.8 × 12.8 µm, L/W 1.3; a prominent Stieda and subStieda body was present; a sporocyst residuum was present and composed of numerous spheroidal granules dispersed into small and large granules. Sporozoites lie lengthwise and parallel in a semi-spiral in sporocyst; a spheroidal anterior refractile and posterior refractile body is present; a single nucleus is located between the 2 refractile bodies. This represents the first report of a caryosporan reported from H. platirhinos as well as the only known coccidian from this host. A summary of hosts of C. lampropeltis is provided.

A New Species of Eimeria (Apicomplexa: Eimeriidae) from Green Frog, Lithobates clamitans (Anura: Ranidae) from Arkansas, U.S.A.

Between April and October 2012, 20 juvenile and adult green frogs (Lithobates clamitans) were collected by hand or dipnet from 3 counties of Arkansas and examined for coccidial parasites. A single frog (5%) was found to be passing oocysts of a new eimerian species. Oocysts of Eimeria menaensis n. sp. were ellipsoidal to subspheroidal with a bilayered wall and measured (L × W) 25.4 × 15.6 (23-27 × 13-17) µm, with a L/W ratio of 1.6. A micropyle was absent but an oocyst residuum and polar granule were present. Sporocysts were spheroidal to subspheroidal and measured 5.0 × 5.0 (4-6) µm with L/W of 1.1. An indistinct Stieda body was present, but sub-and para-Stieda bodies were absent. The sporocyst residuum consisted of condensed granules dispersed between sporozoites. Sporozoites were elongate and attenuated at both ends with spheroidal anterior and posterior refractile bodies. This represents the second report of coccidia from L. clamitans and the first time a coccidian has been reported from a green frog from Arkansas.

CHARACTERIZATION OF EIMERIA LANCASTERENSIS AND EIMERIA ONTARIOENSIS (APICOMPLEXA: EIMERIIDAE) FOUND IN EASTERN GRAY SQUIRRELS, SCIURUS CAROLINENSIS (RODENTIA: SCIURIDAE), FROM ARKANSAS AND OKLAHOMA.

We report the morphological characteristics of oocysts of Eimeria lancasterensisJoseph, 1969, collected from 6 of 6 (100%) eastern gray squirrels, Sciurus carolinensis, collected in Arkansas (n = 3) and Oklahoma (n = 3), and Eimeria ontarioensisLee and Dorney, 1971, recovered from an individual of S. carolinensis from Arkansas. Oocysts of E. lancasterensis were ovoidal to ellipsoidal, measuring (L × W) 24.0 × 14.6 (18-29 × 12-16) µm; shape index (L/W) was 1.6 (1.3-1.8). A micropyle and an oocyst residuum were absent, but up to 2 polar granules were present. Oocysts of E. ontarioensis were piriform and measured 40.6 × 26.0 (37-44 × 23-28); L/W was 1.6 (1.5-1.7). These oocysts possessed a distinct micropyle and rarely a polar granule but lacked an oocyst residuum. The DNA was isolated from both eimerians, and the 18S rDNA genetic markers were PCR-amplified, cloned, sequenced, and analyzed. To our knowledge, this study represents the first time 18S DNA sequence data have been generated from E. lancasterensis and E. ontarioensis found in North American sciurid hosts, as well as new geographic distribution records for these coccidians. In addition, we also include a tabular summary of these 2 species of Eimeria from Sciurus spp. worldwide, with information on their hosts, distribution, and taxonomically important morphological characteristics, including key measurements of oocysts and sporocysts.

Two new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) from emerald tree skinks, Lamprolepis smaragdina (Lesson) (Sauria: Scincidae) from Papua New Guinea and the Philippines.

Two new species of Eimeria Schneider, 1875, from emerald tree skinks, Lamprolepis smaragdina (Lesson) are described from specimens collected in Papua New Guinea (PNG) and the Philippines. Oöcysts of Eimeria nuiailan n. sp. from the only L. smaragdina from PNG are ovoidal, with a smooth, colourless, bi-layered wall, measure 23.7 × 19.1 µm, and have a length/width (L/W) ratio of 1.3; both micropyle and oöcyst residuum are absent, but a fragmented polar granule is present. Sporocysts are ovoidal to ellipsoidal, 11.9 × 7.0 µm, L/W 1.7, and the wall is composed of two valves joined by a longitudinal suture; neither Stieda nor sub-Stieda bodies are present; a sporocyst residuum is present as a compact mass of granules. Sporozoites are elongate, 14.6 × 2.6 µm, and contain anterior and posterior refractile bodies with a nucleus between them. Oöcysts of Eimeria auffenbergi n. sp. from L. smaragdina collected in the Philippines are ovoidal, with a smooth, colourless, bi-layered wall, measure 19.9 × 15.8 µm, L/W 1.3; both micropyle and oöcyst residuum are absent, but one to four polar granules are present. Sporocysts are ovoidal to ellipsoidal, 10.3 × 5.8 µm, L/W 1.8, and the wall is composed of two valves joined by a longitudinal suture; neither Stieda nor sub-Stieda bodies are present; a sporocyst residuum is composed of dispersed granules.

Competitive release during fire succession influences ecological turnover in a small mammal community.

Ecologists have long debated the relative importance of biotic interactions versus species-specific habitat preferences in shaping patterns of ecological dominance. In western North America, cycles of fire disturbance are marked by transitions between North American deermice (Peromyscus maniculatus), which predominate after wildfires, and southern red-backed voles (Myodes gapperi), which gradually replace deermice 3-4 years postfire and maintain dominance as forests mature. While this shift has been frequently documented, the processes that mediate this turnover are debated. One possibility is competitive release, which predicts a reduction in vole competition may contribute to niche expansion and population growth in deermice. Alternatively, turnover in both species may be shaped by differences in their preferred habitat and resource base, as predicted by optimum foraging theory. We evaluate these hypotheses using stable isotopes and spatial mark-recapture of deermouse and vole populations sampled prior to and following a fire as part of a longitudinal study in the Greater Yellowstone Ecosystem. Fire disturbance was associated with a 94% decrease in vole abundance but a 102% increase in deermice. Even after accounting for microhabitat, vole and deermouse populations were negatively correlated spatially and temporally (R = -0.45), and competitor abundance was more important prefire than postfire. When vole abundance was high (prefire), vole dietary niche space was seven times broader than that of deermice. Postfire, deermouse dietary niche nearly tripled and was enriched in 13 C (i.e., more C4 plants), while voles occupied a slightly reduced dietary niche (79% of prefire breadth). Our results suggest deermice are experiencing ecological release due to a reduction in vole competition but vole shifts are largely driven by habitat preferences.

A New Isospora (Apicomplexa: Eimeriidae) from the Summer Tanager, Piranga rubra (Aves: Passeriformes: Cardinalidae), in Oklahoma.

The summer tanager, Piranga rubra (L., 1758) is a medium-sized songbird formerly belonging to the tanager family Thraupidae but now has been placed within the family Cardinalidae. Nothing is known about the coccidian parasites of this stunningly colorful bird. Feces from 2 P. rubra found dead in McCurtain County, Oklahoma were collected and examined for coccidia; 1 was found to be passing a new species of Isospora. Oocysts of Isospora mccurtainensis n. sp. are subspheroidal to ovoidal with a smooth bilayered wall, measure (length × width [L × W]) 21.7 × 19.5 µm, and have a L/W ratio of 1.1; a micropyle and oocyst residuum were absent but a bilobed and refractile polar granule is present. Sporocysts are ellipsoidal and measure 13.9 × 8.6 µm, L/W 1.6; a knoblike Stieda body is present as well as a distinct sub-Stieda body. The sporocyst residuum is composed of a granular compact cluster with a dense, irregular mass of granules lying between and dispersed among the sporozoites. This is the first coccidian reported from P. rubra and, most important, only the first known from the Cardinalidae in the mainland of the United States.

A NEW SPECIES OF EIMERIA (APICOMPLEXA: EIMERIIDAE) FROM THE OLIVE-BACKED POCKET MOUSE, PEROGNATHUS FASCIATUS (RODENTIA: HETEROMYIDAE: PEROGNATHINAE), FROM WYOMING.

Forty-nine olive-backed pocket mice, Perognathus fasciatus were collected during 2011 and 2012 from 4 sites in Wyoming and examined for coccidian parasites. Fifteen (31%) were found to be passing oocysts of a new species of Eimeria Schneider, 1875. Sporulated oocysts of Eimeria fasciata n. sp. are ellipsoidal to ovoidal, 23.3 × 20.7 (19-27 × 17-25) µm, with a shape index of 1.1; they typically contain a single, smooth, bubble-like oocyst residuum. Oocysts possess 1-2 polar granules, lack a micropyle, and are bilayered with a thickness of 1.3 µm. Sporocysts are ovoidal, 10.0 × 8.2 (8-12 × 7-10) µm, with a shape index of 1.2; they contain a sporocyst residuum that appears similar to a cluster of 1-8 grapes. The Stieda body is small, appearing flattened to knobby, and there are no subStieda or paraStieda bodies. This new eimerian represents the only coccidian, to date, reported from P. fasciatus, as well as the only species from any heteromyid rodent in Wyoming.

A New Isosporan (Apicomplexa: Eimeriidae) from Wood Thrush, Hylocichla mustelina (Aves: Passeriformes: Turdidae), in Oklahoma.

The wood thrush, Hylocichla mustelina, is a North American passerine bird closely related to other thrushes and is widely distributed across North America. Nothing is known of the coccidian parasites of this bird. Feces from a single H. mustelina found dead in McCurtain County, Oklahoma were collected and examined for coccidia; it was found to be passing a new species of Isospora. Oocysts of Isospora gmelini n. sp. are subspheroidal to ellipsoidal with a smooth bilayered wall, measure (length [L] × width [W]) 19.5 × 16.5 µm, and have a L/W ratio of 1.2; a micropyle and oocyst residuum were absent but polar granule(s) are present. Sporocysts are ellipsoidal to elongate and measure 13.4 × 8.9 µm, L/W 1.5; a buttonlike Stieda body is present, but sub-Stieda and para-Stieda bodies are absent. The sporocyst residuum is composed of a compact spheroid with a dense, irregular mass of finer granules lying between and dispersed among the sporozoites. Although several isosporans have been reported from other turdid birds, mainly from Brazil and Costa Rica, this is the initial coccidian reported from H. mustelina and only the second known from the Turdidae in the mainland of the United States.

Coccidian Parasites of Flying Squirrels, Glaucomys spp. (Rodentia: Sciuridae), from Alaska and Arkansas, with a Description of a New Species of Eimeria (Apicomplexa: Eimeriidae).

New World flying squirrels, Glaucomys spp., are nocturnal arboreal sciurid rodents that have been previously surveyed for coccidial parasites. To date, 4 species of Eimeria have been reported from 2 species of Glaucomys. Here we report 2 species of eimerians from southern flying squirrels (Glaucomys volans) and the endemic Prince of Wales flying squirrel (Glaucomys sabrinus griseifrons). Oocysts of Eimeria dorneyi Levine and Ivens were found to be passing in the feces of 4 G. s. griseifrons from Alaska and a new species of Eimeria was present in feces from 6 G. volans from Arkansas. Oocysts of Eimeria hnidai n. sp. are ellipsoidal with a bilayered wall, measure 23.7 × 13.7 µm, and have a length/width (L/W) ratio of 1.7; a micropyle and oocyst residuum are absent but polar granule(s) are present. Sporocysts are ellipsoidal-elongate and measure 11.8 × 4.9 µm, L/W 2.2; Stieda body is present but sub-Stieda and para-Stieda bodies are absent. The sporocyst residuum is composed of small indistinct granules along the edge or in the center of the sporocyst. This is the first coccidian reported from G. volans from Arkansas as well as the initial coccidian (E. dorneyi) reported from G. s. griseifrons from Alaska. We also provide a summation of the coccidia known from North American flying squirrels.

Species of Eimeria (Apicomplexa: Eimeriidae) from tree squirrels (Sciurus niger) (Rodentia: Sciuridae) and analysis of the ITS1, ITS2, and 5.8S rDNA.

During the winter of 2004, 48 fecal samples were collected from live-trapped fox squirrels (Sciurus niger) from central Wyoming (Natrona County) and examined for species of Eimeria. Two species, Eimeria lancasterensis (prevalence, 65%) and Eimeria ontarioensis (prevalence, 27%), were identified. Genomic DNA sequences ITS1 and ITS2 were amplified, cloned, and sequenced. Additional sequences from E. lancasterensis isolated from a Delmarva fox squirrel (Sciurus niger cinereus) collected on Chincoteague Island, Virginia, were also identified. Comparison of pairwise distances suggests that E. lancasterensis from Wyoming and Virginia are conspecific. Maximum Parsimony tree construction identified 2 lineages, one E. ontarioensis and one E. lancasterensis; and both lineages had a strong bootstrap support (100%). The Maximum Parsimony analysis was unable to resolve the Wyoming and Virginia strains.

Helminth (Cestoda, Nematoda) and coccidian (Apicomplexa: Eimeriidae) parasites of the eastern small-footed myotis, Myotis leibii (Chiroptera: Vespertilionidae) from Arkansas, with a description of a new species of Eimeria.

During May and July 2016, 32 eastern small-footed myotis (Myotis leibii) were collected from five counties of northwestern Arkansas and their faeces examined for coccidian parasites. Four of 32 (13%) M. leibii harboured an eimerian that we describe here as new. Oocysts of Eimeria sassei sp. n. were ovoidal to ellipsoidal with a bi-layered wall and measured (length × width, L × W) 18.3 × 15.2 µm, with an L/W ratio of 1.2. A micropyle and oocyst residuum were absent but 1-2 polar granules were present. Sporocysts were ovoidal, 9.6 × 6.3 µm, with an L/W ratio of 1.5. A pronounced, button-like Stieda body was present but substieda and parastieda bodies were absent. A sporocyst residuum was present as distinct aligned or dispersed granules. One bat that we found dead was examined for helminth parasites. It harbored the tapeworm, Vampirolepis sp. and a nematode, Seuratum cancellatum. This is the first coccidian as well as the second helminths reported from M. leibii. In addition, this is the seventh species of coccidian parasite documented from Arkansas bats.

A new species of Isospora (Apicomplexa: Eimeriidae) from eastern coachwhip, Coluber flagellum flagellum (Reptilia: Ophidia) from Oklahoma.

Between June 2013 and August 2014, four eastern coachwhips, Coluber flagellum flagellum were collected from Arkansas (n = 2) and Oklahoma (n = 2) and their faeces examined for coccidian parasites. One (25%) harboured an isosporan that we describe here as new. Oocysts of Isospora kiamichiensis sp. n. were spheroidal to subspheroidal with a uni-layered wall and measured (length × width, L × W) 25.0 × 22.2 µm, with an L/W ratio of 1.1. A micropyle, oocyst residuum and polar granule were absent. Sporocysts were ovoidal, 13.9 × 9.4 µm, with an L/W ratio of 1.5. A pronounced, button-like Stieda body was present as well as a substieda body. A sporocyst residuum was present as dispersed granules. This is the first isosporan and fourth coccidian reported from eastern coachwhip snakes. In addition, a single oocyst of an unknown choleoeimerian was recovered from this host.

A new species of Eimeria (Apicomplexa: Eimeriidae) from tri-colored bats, Perimyotis subflavus (Chiroptera: Vespertilionidae), from the Ouachitas of Arkansas.

Between February 2013 and October 2013, eleven tri-colored bats, Perimyotis subflavus were collected from Marion, Polk, and Searcy counties, Arkansas, and their faeces examined for coccidian parasites. Two of eleven (18%) harboured an eimerian that we describe here as new. Oocysts of Eimeria mcdanieli sp. n. were ellipsoidal to elongate with a bi-layered wall and measured (length × width, L × W) 28.3 × 17.9 µm, with an L/W ratio of 1.6. A micropyle and oocyst residuum were absent but a single polar granule was present. Sporocysts were ovoidal, 12.6 × 8.3 µm, with an L/W ratio of 1.5. A pronounced, nipple-like Stieda body was present as well as a substieda body. A sporocyst residuum was present as dispersed bubble-like granules. This is the third coccidian described from tri-colored bats and the sixth species reported from Arkansas chiropterans. In addition, both infected bats harbored a concurrent infection of Eimeria heidti McAllister, Burt, Seville, and Robison, 2011.

A new caryosporan and eimerian (Apicomplexa: Eimeriidae) from green anoles, Anolis carolinensis (Sauria: Dactyloidae), from Arkansas and Louisiana, with a summary of the coccidia of Dactyloidae.

Between April 2012 and September 2013, feces from 18 green anoles, Anolis carolinensis from Arkansas (n = 14), Louisiana (n = 1), and Oklahoma (n = 3) were examined for coccidia. Two species of coccidians were found, including a new caryosporan and a new eimerian. Oocysts of Caryospora natchitochesensis n. sp. from a single A. carolinensis from Louisiana were subspheroidal to ovoidal with a smooth, yellow-to-brown-pigmented, bilayered wall of equal thickness (∼0.3-0.7) and measured (L × W) 13.1 × 12.3 µm, with a length/width (L/W) ratio of 1.1. A micropyle and oocyst residuum were absent, but a polar granule was present. Sporocysts were ovoidal and measured 10.1 × 7.4 µm, L/W was 1.4. A Stieda body (∼1.0 µm) was present, but substieda and parastieda bodies were absent. The sporocyst residuum was composed of dispersed granules or globules among sporozoites. Oocysts of Eimeria robisoni n. sp. from 1 of 12 (8%) green anoles from Arkansas were ellipsoidal with a smooth, unilayered wall (∼0.4-0.5) and measured (L × W) 14.5 × 10.5 µm, with L/W ratio of 1.4. A micropyle and oocyst residuum were absent, but 1-4 (usually 2) polar granules were present. Sporocysts were subspheroidal to ovoidal and measured 5.8 × 4.9 µm, L/W was 1.2. Stieda, substieda, and parastieda bodies were absent. The sporocyst residuum was composed of dispersed granules between sporozoites. None of the anoles from Oklahoma was found to be passing oocysts. This is the second time an eimerian and a caryosporan have been reported from green anoles. A summary of the coccidians of lizards of the family Dactyloidae is provided, with special emphasis on the Anolis of the United States.

A new species of coccidia (Apicomplexa: Eimeriidae) from Cordillera striped shrew-rat, Chrotomys whiteheadi (Rodentia: Muridae), from the Philippines.

During July 2011, a single Cordillera striped shrew-rat (Chrotomys whiteheadi) was collected from the Philippines and its faeces examined for coccidian parasites. It harboured an eimerian that we describe here as new. Oocysts of Eimeria macarthuri sp. n. were spheroidal to subspheroidal with a bi-layered wall and measured (length × width, L × W) 18.2 × 17.0 µm, with an L/W ratio of 1.1. A micropyle, oocyst residuum and polar granule were absent. Sporocysts were ovoidal, 9.0 × 6.4 µm, with an L/W ratio of 1.3. A nipple-like Stieda body was present as well as a substieda body. A granular sporocyst residuum was present. To our knowledge, E. macarthuri represents the only coccidian ever described from a rodent of the Philippines.