Ornate Box Turtles Research Articles

Emydomyces testavorans Surveillance in Multiple Free-Ranging Terrestrial and Aquatic Chelonian Species in Illinois, USA.

The order Onygenales contains multiple fungal pathogens that affect free-ranging and zoo-housed reptilian species. Emydomyces testavorans, an onygenalean fungus associated with skin and shell disease, has been sporadically detected in aquatic chelonians. Because of the recent discovery of this organism, little is known about its prevalence in free-ranging chelonians. The objective of this study was to perform surveillance for E. testavorans in six free-ranging aquatic and terrestrial chelonian species in Illinois, USA: Blanding's turtles (n=437; Emydoidea blandingii), painted turtles (n=199; Chrysemys picta), common snapping turtles (n=35; Chelydra serpentina), red-eared sliders (n=62; RES; Trachemys scripta elegans), eastern box turtles (n=73; Terrapene carolina carolina) and ornate box turtles (n=29; Terrapene ornata). Combined cloacal-oral swabs (COSs) or shell (carapace and plastron surfaces) swabs were collected from 2019 to 2021 and tested for E. testavorans using quantitative PCR. The PCR detected E. testavorans in COSs of an adult male, subadult female, and juvenile male Blanding's turtle (0.6%; 95% confidence interval [CI], 0.2-1.9%) and a shell swab from an adult female RES (1.6%; 95% CI, 0-8.7%). Shell lesions consistent with E. testavorans infection were present in two of the positive Blanding's turtles. These results document the rarity of this pathogen on the landscape in Illinois. Additional studies should determine this pathogen's impact on individuals and clarify its significance for conservation efforts of Blanding's turtle, in which E. testavorans has not been reported previously.

Variable Rates of Parasitism on Ornate Box Turtles (Terrapene ornata) in Eastern Kansas by the Chelonian-Specific Ectoparasite Cistudinomyia cistudinis

Variable Rates of Parasitism on Ornate Box Turtles (Terrapene ornata) in Eastern Kansas by the Chelonian-Specific Ectoparasite Cistudinomyia cistudinis

Evaluating population persistence of ornate box turtles (Terrapene ornata) at the northeast edge of their distribution

Turtles and tortoises are among the most threatened vertebrate groups. Their life history is characterized by delayed sexual maturity and a long lifespan, making populations susceptible to decline following perturbations. Despite the urgent conservation need, we are missing estimates of basic demographic traits for many species and populations. The ornate box turtle Terrapene ornata is a species lacking crucial demographic data. Many populations are isolated in fragmented habitats, especially in the eastern portion of their range. We carried out long‐term capture–mark–recapture surveys on two isolated populations in northern Illinois to estimate population vital rates and project population persistence with deterministic stage‐based matrix models. Using 34 years of data, we estimated adult female survival = 0.974 (95% CI: 0.946–0.988) and juvenile survival = 0.867 (95% CI: 0.688–0.951) at our most intensively surveyed site. At a second site using eight years of data, we estimated adult female survival = 0.897 (95% CI: 0.783–0.954) and juvenile survival = 0.844 (95% CI: 0.551–0.960). Despite seemingly high annual survival rates, populations declined under population projections using mean vital rates. Population growth was most sensitive to adult survival, with increasing sensitivity under more pessimistic scenarios. Our results highlight the importance of long‐term demographic studies for threatened species and demonstrate protecting adult female ornate box turtles is critical for ensuring populations persist at the northern edge of their distribution.

Avoiding mortality: timing prescribed burns in ornate box turtle habitat

AbstractFire is a vital management tool for maintaining prairie ecosystems. Prescribed burns control invasive species, regulate succession, stimulate plant growth, and are a cheap and effective method for removing excess biomass; however, fire can also inadvertently cause wildlife mortality, placing land managers in a challenging situation. Turtles are especially at risk of mortality from fire because of their low mobility and population sensitivity to reductions in adult survival. We studied ornate box turtles (Terrapene ornata) at 3 sites in Illinois, USA, from 2019–2022 to determine the best predictors of above‐ground activity so land managers can conduct prescribed burns when turtles are underground. We used turtle shell temperature, air temperature, soil temperature, and precipitation data to develop a predictive model of above‐ground activity. The best model for predicting above‐ground activity included an interaction between day of year and current air temperature. Earlier in spring and later in fall, above‐ground activity is more likely at higher air temperatures compared to later in spring and earlier in fall when the same likelihood of above‐ground activity is predicted at lower air temperatures. In spring, we recommend burning in Illinois ornate box turtle habitat before 1 April when air temperature is <10°C and in fall after 1 November when air temperature is <15°C. Above these temperature thresholds, there is a >5% likelihood that turtles in northern populations are above ground.

Home ranges of Ornate Box Turtles in remnant prairies in north-central Illinois

Habitat loss has been a primary driver of biodiversity declines throughout the United States. Native prairie ecosystems represent some of the most significant losses in land cover, and subsequently, prairie-dependent species are some of the most imperiled. Therefore, understanding the ecology of species remaining in remnant portions of these ecosystems is important to help manage their populations. Using radio-telemetry, we examined minimum convex polygon (MCP) and 95% kernel density (KD) home ranges of 20 (5 females, 15 males) Ornate Box Turtles (Terrapene ornata) inhabiting two remnant prairies in north-central Illinois across two years and six seasons. Results showed that MCP and 95% KD home range estimates were comparable but smaller than other published studies, differed between years, across seasons, and among individual turtles within sites. These results provide valuable data to quantify the ecology of this threatened species in a remnant prairie habitat.

Effects of Prairie Degradation and Restoration on Box Turtle Thermal Ecology

Prairie habitat loss in the United States has led to population declines in many prairie-associated species, including Ornate Box Turtles (Terrapene ornata). Northwest Arkansas is an intergrade zone between the prairie-dwelling T. ornata and the more forest-associated Three-Toed Box Turtle (Terrapene carolina). As such, limited information exists on the potential differences in physiology and thermal ecology between the two box turtle species and how those differences might influence their habitat use. We addressed gaps in our knowledge of the thermal and spatial ecology of T. ornata and T. carolina with a three-part study. First, we compared the thermal profiles of refugia, open, and vegetated microhabitats across degraded prairie, restored prairie, and adjacent forest macrohabitats using operative temperature models and a linear mixed effect model. Second, we measured total evaporative water loss of both species across a range of body sizes. Finally, we fitted a subset of turtles with iButton data loggers and monitored them in the field to examine carapace temperatures and habitat use. Operative temperature models recorded high, largely homogeneous temperatures across microhabitats in degraded prairie and heterogeneous temperatures across restored prairie microhabitats, while forest habitat maintained stable, cool temperatures. Both species exhibited similar evaporative water loss rates; however, T. ornata experienced a broader range of temperatures in the field. Terrapene ornata were exclusively found in prairie habitat, whereas T. carolina was often found in forested habitats and subsurface refugia. Our results demonstrate key differences in box turtle thermal biology and highlight suboptimal thermal characteristics in degraded prairie and forest habitat that should be considered in prairie restoration and management for T. ornata conservation.

Do Home Range, Movement Patterns, and Habitat Use of Ornate Box Turtles (Terrapene ornata ornata) Differ Among Age Classes?

Ornate Box Turtles (Terrapene ornata ornata) exist in few large, reproductive populations in Iowa. Little is known about the home range, movements, and habitat use of neonates and young turtles or how movements change during maturation. We tracked four age classes of turtles from 2011 to 2016 and calculated weekly minimum convex polygon home range, every-other-day linear distance moved, habitat, microhabitat, and vegetation cover. We divided the active season into three blocks of time based on established patterns of behavior in Ornate Box Turtles. Age was the only significant factor explaining larger home ranges in older turtles during May and June–July, but there were no significant differences during August–September. However, linear distance moved significantly increased with age during all time periods. Turtles were mainly found in prairie or shrub–prairie habitats, but older turtles were more likely to move farther away from the nesting/breeding/overwintering area. While often on the surface, all age groups were found primarily under vegetation, shrubs, or trees that provided >95% vegetation cover. We suggest that habitat management for this state-threatened species consider the diverse habitats and area needed by all age classes.

Prevalence of Intraerythrocytic Parasites in Macrochelys temminckii, Emydoidea blandingii, Terrapene carolina, and Terrapene ornata

Few studies have characterized the prevalence of intraerythrocytic parasites in free-ranging chelonian populations or their occurrence across habitats. It is hypothesized that chelonians in different habitats have different exposures to vectors and thus, differences in hemoparasite presence. This study explored the prevalence and intensity of intraerythrocytic parasites by examining blood smears from four species of Illinois turtles: wild Blanding’s turtles (Emydoidea blandingii), eastern box turtles (Terrapene carolina carolina) (EBT), and ornate box turtles (Terrapene ornata ornata) (OBT) and headstarted alligator snapping turtles (Macrochelys temminckii) (AST). Intraerythrocytic parasites were identified in all examined species except for the alligator snapping turtle. For all age classes, Blanding’s turtles had both the highest prevalence of hemoparasites and intensity of infection of all sampled species, while adult Blanding’s turtles had a significantly higher prevalence than juveniles (P<0.05). As this is the first study of hemoparasites in Illinois chelonians, further research is needed to identify the specific species of intraerythrocytic parasite, the potential vectors, and the effect these hemoparasites have on the health of chelonians.

Understanding Habitat Use and Activity Patterns of Ornate Box Turtle (Terrapene ornata) in Eastern New Mexico

The ornate box turtle (Terrapene ornata) is a terrestrial Emydid, listed as near threatened by the International Union for Conservation of Nature Redlist due to habitat destruction, degradation, habitat fragmentation, commercial harvest, and road mortality. Terrapene ornata is secretive, which can pose a challenge to conducting systematic surveys and assessing species status. Studies on the species' biology have relied on opportunistic encounters on the road and the use of radiotelemetry. The objective of this study was to assess the feasibility of using transect line surveys in single season occupancy surveys for T. ornata in Roosevelt County, New Mexico. We further used radiotelemetry to link turtle activity patterns with environmental conditions to aid in understanding detectability of the species. Our occupancy model showed the detection probability to be influenced by individual observers and the time of day. We found T. ornata to most likely occupy habitats with less dense ground cover and avoid highly altered habitats (i.e., cultivated fields). Radiotelemetry further revealed the effect humidity, time of day, and temperature on turtle activity patterns. The lowest activity occurred between 1200–1700 h, whereas peak activity occurred in early morning hours (0600–0900 h). The peak activity occurred between ∼10–25 C and was promoted by higher humidity. Our study represents the first attempt at using transect line surveys for occupancy modeling framework for the ornate box turtles. We suggest that future studies on box turtle occupancy focus on finer scale habitat assessment that would also include vegetation, invertebrate, and small mammal surveys.

Evaluation of a dexmedetomidine–midazolam–ketamine combination administered intramuscularly in captive ornate box turtles (Terrapene ornata ornata)

ObjectiveTo characterize the effects of a combination protocol of dexmedetomidine–midazolam–ketamine (DMK) administered intramuscularly (IM) in ornate box turtles (Terrapene ornata ornata). Study designProspective experimental trial. AnimalsA total of 16 apparently clinically healthy adult ornate box turtles (eight male, eight female). MethodsEach turtle was treated with dexmedetomidine (0.1 mg kg−1), midazolam (1 mg kg−1) and ketamine (10 mg kg−1) administered IM. Time to first response, time to maximal effect, the plateau phase and time to recovery from reversal administration were recorded. Physiologic variables, muscle tone, reflexes and the ability to perform endotracheal intubation were recorded at 5 minute intervals. Movement in response to an IM injection of 0.1 mL sterile 0.9% NaCl administered in the left pelvic limb, using a 25 gauge needle to a depth of just past the bevel of the needle, was assessed every 15 minutes. Atipamezole (0.5 mg kg−1) IM and flumazenil (0.05 mg kg−1) SC were administered 60 minutes after the initial DMK injections. ResultsThe mean time to first response, time to maximal effect, the plateau phase and time to recovery were 2.1, 14.9, 38.7 and 7.8 minutes, respectively. A respiratory rate was not observed in most turtles. The body temperature significantly increased over time. The palpebral reflex was persistent in 43% of turtles and the tail pinch reflex remained intact in 13% of turtles. All turtles recovered with no observed adverse effects. Conclusions and clinical relevanceIn this study, this DMK protocol administered to ornate box turtles resulted in a rapid-onset, light anesthesia lasting approximately 40 minutes and a smooth recovery with no adverse effects noted.

Ornate Box Turtles (Terrapene ornata) copulating in water: an incidental observation or ancestral behavior

Herein, we report the first observation of the terrestrial Ornate Box Turtle (Terrapene ornata) copulating in water. To understand whether such an event reflected an isolated incident, we compiled observations reported in the literature of copulatory behaviors in water for other North American turtles. Our literature review revealed that other species of box turtles in North America, the Coahuilan Box Turtle (Terrapene coahuila) and Gulf Coast Box Turtle (Terrapene carolina major), occasionally also copulate in water. The vast majority of turtles in North America copulate in water, as most are semi-aquatic, including all species with observations in the Emydidae family. We did not find observations for water copulations in tortoises (Testudinidae), the most terrestrial group of turtles in North America. Although Ornate Box Turtles are terrestrially adapted, box turtles are within the family Emydidae, the pond turtles. Copulation in this fluid medium for terrestrial species might aid in the reproductive process with increased buoyancy and stability counteracting the high dome-shaped carapace that likely hinders copulation on land. Such a behavior also might help conceal individuals from predators or conspecific males that might disrupt copulating individuals. If ponded water is available within habitats for these terrestrially adapted box turtles, we predict underwater copulatory behaviors might be more common than recognized and remain undetected due to the inconspicuous nature of locations and rarity of ponded water in such habitats.

Erythrocyte sedimentation rate and hemoglobin-binding protein in free-living box turtles (Terrapene spp.)

The acute phase response is a highly conserved reaction to infection, inflammation, trauma, stress, and neoplasia. Acute phase assays are useful for wildlife health assessment, however, they are infrequently utilized in reptiles. This study evaluated erythrocyte sedimentation rate (ESR) in eastern (Terrapene carolina carolina) and ornate box turtles (Terrapene ornata ornata) and hemoglobin-binding protein (HBP) in T. ornata. Erythrocyte sedimentation rate in 90 T. carolina and 105 T. ornata was negatively associated with packed cell volume and was greater in unhealthy turtles (p < 0.05). Female T. ornata had higher ESR values than males (p < 0.05). Measurement of ESR with a microhematocrit tube proportionally overestimated values from a commercial kit (Winpette), though both methods may retain utility with separate reference intervals. Hemoglobin-binding protein concentration in 184 T. ornata was significantly increased in adults and unhealthy turtles (p < 0.05). Erythrocyte sedimentation rate values were similar between seasons and populations, and HBP values were consistent between years, indicating that these analytes may have more stable baseline values than traditional health metrics in reptiles. This study demonstrates that ESR and HBP are promising diagnostics for health assessment in wild box turtles. Incorporating these tests into wild herptile health assessment protocols may support conservation efforts and improve ecosystem health monitoring.

PREVALENCE OF BOX TURTLE ADENOVIRUS IN EASTERN BOX TURTLES (TERRAPENE CAROLINA CAROLINA) PRESENTED TO A WILDLIFE REHABILITATION CENTER IN VIRGINIA, USA.

Eastern box turtles (Terrapene carolina carolina) are a native North American species with a declining population trend that may be attributable to habitat fragmentation, vehicle collisions, and disease. Adenoviral infections can cause significant morbidity and mortality in captive reptile populations. Adenoviruses have been documented in box turtles, but their occurrence and impact in wild populations are unknown. A disease survey was performed at The Wildlife Center of Virginia, USA, to assess the prevalence of box turtle adenovirus (BTAdV) in wild eastern box turtles and evaluate potential associations with clinical disease. Swabs from the oral cavity, including the choanal slit, and the cloaca were collected from 106 eastern box turtles from July 2015 through June 2016. The quantitative polymerase chain reaction (qPCR) primer detected both ornate box turtle adenovirus 1 and eastern box turtle adenovirus. The resulting qPCR adenovirus prevalence was 55.7% (n = 59). Most animals (99.3%) that tested positive for BTAdV had fewer than 100 viral copies/ng DNA. This study did not find a statistically significant association between cause of admission, age, sex, outcome, and BTAdV qPCR status. However, the probability of BTAdV detection was 1.5 times higher in rehabilitation turtles compared with wild turtles (P = 0.01). Albumin was significantly lower in qPCR BTAdV-positive turtles (P = 0.007). Hypoalbuminemia is not generally associated with adenovirus infections in other species, and no obvious clinical cause for this abnormality was identified. The results of this study suggest that eastern box turtles may harbor BTAdV infections at low levels and that infection is rarely associated with clinical disease, potentially identifying BTAdV as a host-adapted pathogen. Future studies should focus on this pathogen's ability to induce clinical disease and its potential impact on recovery efforts for this species.

A Surfeit of Studies: What Have We Learned from All the Box Turtle (Terrapene carolina and T. ornata) Home Range Studies?

Home range (HR) studies are a particularly common approach to investigations of animal habitat use, resource availability, and response to management manipulation such as relocations. Terrapene carolina (Eastern box turtle) and its sister taxon T. ornata (Ornate box turtle) are especially popular subjects of HR studies because they are relatively easily tracked. Terrapene HR studies have revealed a wide variation in HR sizes within and between populations, due to factors such as differences in ecoregion and analytical approach (e.g., minimum convex polygons, kernel analysis, bivariate normal, multivariate Ornstein–Uhlenbeck stochastic process, harmonic means). We performed a meta-analysis of the available literature, including unpublished work to avoid bias due to under-publication, to explore the causes for variation in HR size. We found 19 studies reporting T. carolina HR sizes and seven studies reporting T. ornata HR sizes; the resulting meta-analysis revealed patterns that are not visible in the individual studies. We found important differences between the species: female T. ornata had smaller HRs than males, whereas the opposite is true for T. carolina, and T. ornata HRs were influenced by ecoregion, while T. carolina HRs were not similarly influenced. Not surprisingly, we found that choice of analysis technique affected HR estimate; analyses using ellipses resulted in larger HR estimates than all the other techniques, while kernels were smaller than minimum convex polygons. Although not indicated by individual studies, our meta-analysis showed that the HRs of relocated T. carolina females were significantly larger than those of non-relocated females. Although the number of individual turtles in studies varied from three to 25, the sample size did not significantly affect HR size.

Habitat Characteristics and Selection by Ornate Box Turtles in the Sandhills of South Dakota

The ornate box turtle (Terrapene ornata Agassiz) is a species of greatest conservation need in South Dakota. Habitat loss through agricultural development and fragmentation is the main threat to the species throughout its range, which extends from Wisconsin and northern Indiana through the central Great Plains, and from southern South Dakota to Arizona, northern Mexico, and the Gulf Coast of Texas. The objectives of this study were to determine the ornate box turtle's preferred vegetation characteristics (microhabitat) compared to the available habitat (macrohabitat) on the Pine Ridge Reservation, South Dakota Sandhills region, during 2010–2011. In both years, using a modified Robel pole method, we determined that turtles selected microhabitat with greater visual obstruction readings (VORs) than those within the random available macrohabitat (P < 0.01), with means of 22 cm and 15 cm, respectively. Higher VOR values indicate greater vegetation height and/or density. Canopy cover results showed that ornate box turtles exhibited high selection (P < 0.01) for sand sagebrush (Artemisia filifolia Torr.) coverage (38%) but selected lower cover than available within the macrohabitat for total grasses (37%), total forbs (19%), and bare ground (14%). Shrubs, such as sand sagebrush, are an important component of box turtle microhabitat, as they facilitate thermoregulation by providing cool areas during the summer and favorable hibernation sites during the winter. Shrub coverage is highly reco mmended for consideration when developing habitat management plans that aim to increase or sustain ornate box turtle populations in the Sandhills ecological type.

Morphometric Models of Growth in Ornate Box Turtles (Terrapene ornata ornata) as Related to Growth Rings

Few studies document early growth of hatchling turtles. We fit growth models to 606 carapace length (CL) measurements of ornate box turtles (Terrapene ornata ornata) for 231 males, 226 females, and 53 individuals of undetermined sex. We used the Richards model to fit 95% confidence bands and 95% prediction bands on the best-fit curves for males and females. We also computed Spearman's rho correlation relating growth ring counts to CL and plotted change in CL for 131 recaptured individuals (45 males, 57 females, and 29 individuals of undetermined sex) for which we had two or more measurements from different years. There was a strong correlation between CL and number of growth rings. Using the properties of the derivative of Richards growth model, juvenile 1, juvenile 2, subadult, and adult stages were defined for male and female growth. Our overall growth models were similar to those for studies of ornate box turtles in Kansas and South Dakota and the desert box turtle (T. o. luteola) in New Mexico; however, our growth stages were defined by smaller turtles. Unlike a previous study in South Dakota, our adult males were larger than adult females. Prior to a CL of approximately 86 mm and 8 growth rings, the carapace grew faster than the plastron, after which the plastron grew faster than the carapace. Five hatchlings' plastra grew an average of 26% (SD = 14%) the first year and the carapace grew an average of 15% (SD = 7%). During the first 3 yrs, most individuals developed only one growth ring per year. If major growth rings approximate age, size can be used to estimate age in ornate box turtles up to 60–90 mm (about 8 growth rings). Between 8 and 12 growth rings, size and age are also correlated, but accuracy of age estimates decreases. Life-history traits such as age at reproductive maturation and size at which individuals are vulnerable to predation are important to assess long-term viability of a population; therefore, understanding environmental impacts on individual growth is important for conservation planning and management of this threatened species in Iowa.

Road Mortality of Vertebrates Along Two-Lane Highway in Southcentral Kansas: Historical Data from the 1980's

Road kills impact many wildlife species, but only a limited number of studies have included small animals during these surveys. This study described the road mortality for large, medium and small vertebrates, which includes amphibians, reptiles, small mammals and birds. A 32.2 km stretch of Kansas Highway K254 was surveyed from 31 May 1985 thru 20 May 1987. Eighty-eight species comprised the 4484 individuals found during this study. The road mortality for mammal and bird groups here resembled those reported in other studies, but differed from those reported for herpetofauna group. Ornate box turtle, prairie kingsnake and gopher snake sustained higher road mortalities than found in previous studies. Wildlife also experienced greater road mortality in a landscape where prairie occurred in large contiguous tracts compared with a patchwork of small stands. This study showed that surveying a limited stretch of highway represents a feasible way to obtain accurate road mortality data.

Blood Biochemical Reference Intervals for Wild Ornate Box Turtles ( Terrapene ornata) during the Active Season.

Blood biochemical and hematology analyses are helpful indicators of the physiologic health of animals, particularly when making conservation and management decisions for threatened species. In this study, we 1) established blood biochemical reference intervals for two populations of threatened, free-ranging ornate box turtles ( Terrapene ornata) in northern Illinois during their active season and 2) examined the effects of individual carapace temperature ( Tc) on blood biochemical variables by using a Bayesian hierarchical framework. Individual blood variables differed throughout the active season (May-September 2015), but there were few distinct patterns in concentrations over time. When controlling for individual variability, blood biochemical variables potassium, sodium, chloride, ionized calcium, hematocrit (percentage of packed cell volume), and osmolality showed no effect of Tc (i.e., slope estimates for these variables were not credibly different from zero) and had little individual variation. Glucose and urea nitrogen were found to have slopes credibly different from zero, with glucose having an estimated positive slope and urea nitrogen having an estimated negative slope, suggesting different relationships in response to Tc when controlling for individual variability. These physiologic blood data will serve as important baseline reference values for the clinical evaluation of wild ornate box turtles presented for veterinary care or for comparison to other studies of wild populations. Further, this study highlights the importance of considering individual-level effects (e.g., Tc) on physiologic health variables.

Thermal consequences of subterranean nesting behavior in a prairie-dwelling turtle, the Ornate Box Turtle (Terrapene ornata)

Many oviparous reptiles deposit eggs in excavated nest chambers, and the location and depth at which eggs are laid can affect predation risk, incubation duration, mortality rates, and hatchling phenotype. Among turtles, nest depth also influences incubation conditions of some large-bodied species, but nest depth is generally expected to vary less among small-bodied species. We monitored nesting behavior of Ornate Box Turtles (Terrapene ornata (Agassiz, 1857)) for two seasons in Illinois. We used direct observations to confirm that, among 31 nesting events, six females oviposited while beneath the substrate surface. Furthermore, comparisons of body length to nest depth indicated that five additional females likely also constructed nests while buried. Nests laid while females were underground were deeper, on average, than other nests (16.7 versus 11.2 cm), and while mean nest temperatures were similar between groups, temperature fluctuations and maximum temperatures were lower among nests that were laid while females were underground. Subterranean oviposition appears to have moderated incubation temperatures by allowing females to deposit eggs at greater depths than would be possible from the surface. This little-documented behavior may be a mechanism for this species to influence the incubation environment, which in turn may influence hatchling phenotypes.

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.