Proc. Helminthol. Soc. Wash. 55(2), 1988, pp. 256-259 Eimeria lineri sp. n. (Apicomplexa: Eimeriidae) from the Mediterranean Gecko, Hemidactylus turcicus (Sauria: Gekkonidae), in Louisiana and Texas CHRIS T. McALLiSTER,1'2 STEVE J. UPTON,3 AND PAUL S. FREED4 1 Renal-Metabolic Lab (151-G), Veterans Administration Medical Center, 4500 S. Lancaster Road, Dallas, Texas 75216 2 Department of Biological Sciences, University of North Texas, P.O. Box 5218, Denton, Texas 76203-5218 3 Division of Biology, Ackert Hall, Kansas State University, Manhattan, Kansas 66506 and 4 Department of Herpetology, Houston Zoological Gardens, 1513 Outer Belt Drive, Houston, Texas 77030 ABSTRACT: Eimeria lineri sp. n. (Apicomplexa: Eimeriidae) is described from the feces of 24 of 47 (51.1%) Mediterranean geckos, Hemidactylus turcicus turcicus (Linnaeus, 1758), in Houston, Texas, and Houma, Lou- isiana, U.S.A. Oocysts of this new eimerian are ellipsoid, 24.8 x 19.5 (21.6-28.0 x 18.4-21.6) /im, with a smooth bilayered wall, ca. 1.5 /mi thick; shape index 1.3 (1.1-1.5) /mi. One (rarely 2 or 3) polar granule(s) is (are) usually present, but a micropyle and oocyst residuum are absent. Sporocysts are ellipsoid, 9.0 x 7.8 (8.2- 9.6 x 7.2-8.8) /im, with a smooth thin wall and faint sutures; shape index 1.2 (1.1-1.3) /im. Stieda and substieda bodies absent; sporocyst residuum present, 4.1 x 4.4 (2.5-5.6 x 3.6-5.6) /tin, composed of numerous granules in a spherical or ellipsoid mass. Sporozoites vermiform, 11.6 x 2.4 (8.8-13.6 x 2.0-2.8) /mi, and arranged head-to-tail within the sporocyst. Each sporozoite contains a single spherical anterior refractile body, a central nucleus, and a spherical or ovoid posterior refractile body. In addition to the new species, 8 (17.0%) of the geckos harbored E. turcicus Upton, McAllister, and Freed, 1988. Observations on prevalence and comparisons with similar species are included. KEY WORDS: Eimeria lineri sp. n., Eimeria turcicus, coccidia, Gekkonidae, Mediterranean gecko, Hemidac- tylus turcicus turcicus, Texas, Louisiana, prevalence, Apicomplexa, Eimeriidae. In the latest reviews of the coccidian parasites duced into the New World along with the host of lizards of the family Gekkonidae, Matuschka (Upton et al., 1988). and Banner! (1986a, b) listed a total of 15 named We had the opportunity to collect and examine and 4 unnamed species of Eimeria and 6 named additional H. t. turcicus from the Houston Zoo, and 2 unnamed species of Isospora from 11 and from another Houston locality, and also from a 5 taxa of geckos, respectively. The vast majority locale in coastal Louisiana. Fecal samples from of these hosts, and likewise their coccidia, occur some of these geckos were positive for oocysts in the Old World. Recently, Upton and Barnard of a previously undescribed species of Eimeria, (1987) and Upton et al. (1988) added 3 addi- which was not observed in our earlier study (see tional species of Eimeria to the list, bringing the Upton et al., 1988). Herein, we provide a de- total number of named eimerians to 18. scription of the new form that we observed, along Upton et al. (1988) examined 38 Mediterra- with prevalence data and comparisons with sim- nean geckos, Hemidactylus turcicus turcicus from ilar species of Eimeria from gekkonid hosts. the Houston Zoological Gardens in Houston, Harris County, Texas. These geckos disperse Materials and Methods freely and are not part of the captive fauna housed From March through June 1987, a total of 47 im- at the Zoo. Mediterranean geckos range naturally mature and adult H. t. turcicus (x ± SD snout-vent over portions of the Old World and, nearly a length = 45.7 ± 8.3, range = 28-56 mm) were collected on the walls of St. Anne's Catholic Church in Harris century ago, were introduced into the New World County (N = 21), from within the reptile and amphib- inadvertently by way of port cities (McCoy, 1970). ian facility of the Houston Zoo (N = 18), and at a Today, H. turcicus occurs throughout much of private residence in Houma, Terrabonne Parish, Lou- the Gulf coastal states from Florida to Texas and isiana (N = 7). Within 48 hr, geckos were killed with an overdose of sodium pentobarbital. Their slit intes- south into Mexico (Conant, 1975). Therefore, it tines, along with portions of feces from the rectum, is possible that coccidian parasites of this gecko were placed in individual vials of 2.5% (w/v) aqueous may actually represent Old World species intro- potassium dichromate (K2Cr2O7). Individual samples 256 Copyright © 2011, The Helminthological Society of Washington 257 were screened by flotation (see below) for the presence of coccidian oocysts, and positive samples containing unsporulated oocysts were mailed to Kansas State Uni- versity and stored at 4°C prior to further examination. In addition, squash preparations were made of intes- tinal tissues from some of the geckos and examined for parasite developmental stages. Samples were spor- ulated at room temperature (ca. 23°C) in petri dishes containing a thin layer of 2.5% K2Cr2O7. Sporulated oocysts were concentrated by centrifugation-flotation in Sheather's sugar solution (specific gravity, 1.18) and examined and photographed using Nomarski interfer- ence-contrast microscopy. Thirty oocysts were mea- sured using a calibrated ocular micrometer and are reported in micrometers, with the means followed by the ranges in parentheses. Results Eimeria lineri sp. n. (Apicomplexa: Eimeriidae) (Figs. 1, 2) DESCRIPTION: Oocysts ellipsoid, 24.8 x 19.5 (21.6-28.0 x 18.4-21.6); shape index (length/ width) 1.3 (1.1-1.5). Wall smooth, about 1.5 1 thick, with a thick outer layer about 1.0 and a thin inner layer about 0.5 thick. Micropyle and 10/jm oocyst residuum absent; one (rarely 2 or 3) polar Figure 1. Line drawing of sporulated oocyst of Ei- granule(s) usually present. Sporocysts ellipsoid, meria lineri sp. n. 9.0 x 7.8 (8.2-9.6 x 7.2-8.8), with a smooth thin wall about 0.5 thick; shape index 1.2 (1.1- of Zoology, State University, Arkansas (ASUMZ 1.3). Sometimes faint sutures can be seen in the 8535-8541, 8649-8665, 8667-8673). sporocyst wall revealing the sporocyst to be com- TYPE LOCALITY: Houston, Harris County, posed of plates. Stieda and substieda bodies ab- Texas, U.S.A. sent. Sporocyst residuum present, composed of OTHER LOCALITIES: Houma, Terrabonne numerous granules in a spherical or ovoid mass, Parish, Louisiana, U.S.A. 4.1 x 4.4(2.5-5.6 x 3.6-5.6). Sporozoites ver- SITE OF INFECTION: Anterior '/> of small in- miform, 11.6 x 2.4(8.8-13.6 x 2.0-2.8) in situ, testine. arranged head-to-tail within the sporocyst. SPORULATION: Exogenous. Oocysts recov- Sometimes faint striations can be observed at ered from the feces were unsporulated and be- the anterior ends of the sporozoites. Each spo- came fully sporulated within 7 days at ca. 23°C rozoite contains a spherical anterior refractile in 2.5% aqueous K2Cr2O7. body, 1.9 (1.6-2.4), and a spherical or ovoid pos- PREVALENCE: 24/47 (51.1%) of the geckos terior refractile body, 2.2 x 2.8 (1.8-2.8 x 1.8- were passing the new species at the time they 3.2). A nucleus can sometimes be observed be- were examined; 17/22 (77.3%) from St. Anne's tween the refractiie bodies. Catholic Church, 4/18 (22.2%) from the Houston TYPE SPECIMENS: Syntypes (oocysts in 10% Zoo, and 3/7 (42.9%) from Houma, Louisiana. formalin) are deposited in the U.S. National Hel- ETYMOLOGY: Named in honor of Ernest A. minthological Collection, Animal Parasitology Liner, in recognition of his numerous contribu- Institute, U.S. Department of Agriculture, Belts- tions to neotropical herpetology. ville, Maryland 20705, as USNM Helm. Coll. REMARKS: Of the hundreds of oocysts ob- No. 80260. served from the geckos from Houston, Texas, all TYPE HOST: Hemidactylus turcicus turcicus but 1 of the oocysts possessed a polar granule. (Linnaeus, 1758) (Sauria: Gekkonidae), Medi- In specimens observed from H. t. turcicus from terranean gecko. Voucher specimens are depos- Louisiana, however, most (but not all) failed to ited in the Arkansas State University Museum possess this structure. Although it is possible that Copyright © 2011, The Helminthological Society of Washington 258 the geckos (2/22 [9.1%] from St. Anne's Church and 6/18 [33.3%] from the Houston Zoo). None of the H. t. turcicus from Houma, Louisiana, harbored E. turcicus. Further, on 1 occasion a single adult female gecko from St. Anne's Church had a polyinfection of both E. lineri and E. tur- cicus. When a Chi-square analysis was performed on the prevalence data, no significant differences based on sex were noted (12/23 [52.2%] males versus 12/24 [50.0%] females). However, when prevalence is examined on the basis of differ- ences in age (measured in snout-vent length, adults being >44 mm) between E. turcicus and E. lineri, contrasting results are obtained. More of the younger geckos (hatchlings and juveniles) and fewer adults harbored E. lineri (41.9 ± 8.3, range 29-54 mm), whereas only the older, more mature adults (52.0 ± 3.2, range 47-56 mm) were infected with E. turcicus. It is unknown whether these trends are a seasonal or ecological Figure 2. Nomarski interference-contrast photo- micrograph of sporulated oocyst of Eimeria lineri: OW phenomenon, the result of differential immu- (oocyst wall), PG (polar granule), RB (refractile body), nological or humoral responses, or whether they SR (sporocyst residuum), SW (sporocyst wall), x 2,100.