Two additional Hepatozoon species (Apicomplexa: Hepatozoidae) from the southern black racer, Coluber constrictor priapus (Serpentes: Colubridae), in northern Florida

Hepatozoon priapus n. sp. from Coluber constrictor priapus has robust gamonts with broadly rounded ends, 18.0 x 4.2 microm (17.0-20.0 x 3.5-6.0), with LW 76.4 microm2 (59-105) and L/W 4.31 (2.9-5.4). The nucleus is always present in second quarter of gamont, seldom extend into first quarter but often into third quarter, 6.0 x 3.0 (5.0-7.0 x 2.5-4.0), with LW 17.9 (13.7-21.0). Erythrocyte cytoplasm is always thin, appearing dehemoglobinized, with infected cells always distorted. Infected erythrocytes are much longer and wider than uninfected cells, with longer nuclei. Oocysts are spherical to ovoid, 92.5 x 86.0 (55-123 x 47-115) and L/W 1.08 (1.0-1.3), contain 14.0 (6-31) sporocysts. Sporocysts, which are also spherical to ovoid, 26.3 x 23.3 (19-50 x 16-38), LW 641.2 (320-1,500) and L/W 1.13 (1.0-2.2), contain 12.6 (5-18) sporozoites. Hepatozoon confusus n. sp., also from C. constrictor priapus, has slender gamonts with rounded ends, 15.6 x 4.1 (14.0-17.0 x 3.5-5.0), with LW 64.3 (52-80) and L/W 3.82 (2.8-4.4). The nucleus is always present in second quarter of gamont, commonly extending into first and third quarters, 5.0 x 2.7 (2.5-4.4 x 4.0-6.0), with LW 13.5 (11.0-16.5). Erythrocyte cytoplasm is sometimes thin, appearing partially dehemoglobinized, with infected cells usually distorted. Infected erythrocytes are longer than uninfected cells but similar in width, with erythrocyte nuclei longer. Oocysts are spherical to ovoid, 115.5 x 108.9 (52-278 x 50-278), with L/W 1.06 (1.0-1.2), and contain 25.0 (7-111) sporocysts. Sporocysts are spherical to ovoid, 27.6 x 25.2 (21-38 x 20-33), LW 701.3 (420-1,125) and L/W 1.09 (1.0-1.4), containing 20.2 (12-32) sporozoites.     

Hepatozoon polytopis n. sp. parasitic in two genera and species of colubrid snakes in southern Florida

Hepatozoon polytopis, described from Coluber constrictor priapus from Palm Beach County, Florida, has short, usually broad gamonts 12.8 x 4.6 microm (10.0-15.0 x 3.5-6.0), with LW 58.5 microm2 (42-84) and L/W 2.84 (1.8-3.7). Nuclei commonly extend into first quarter of gamont (45%), are always present in second quarter, and seldom in third quarter (11%), with dimensions 4.5 x 3.4 (3.0-6.0 x 2.5-4.5) and LW 15.1 (10.0-24.0). Spherical to ovoid oocysts, 122.1 x 104.9 (62-240 x 57-190), with L/W 1.17 (1.0-1.9), contain 31.3 (3-103) sporocysts. Spherical to ovoid sporocysts, 38.0 x 33.9 (28-73 x 25-58), with LW 1,325.1 (756-4,168) and L/W 1.12 (1.0-1.4), contain 42.9 (22-64) sporozoites. Thamnophis sauritus sackenii from Palm Beach County is infected also by H. polytopis, as indicated from similar gamont dimensions and verified by isolation of an identical haplotype of the 18S ribosomal RNA gene from both host species.     

Hepatozoon species of the timber rattlesnake in northern Florida: description of a new species, evidence of salivary gland oocysts, and a natural cross-familial transmission of an Hepatozoon species

Two species of Hepatozoon, i.e., H. sauritus and H. horridus n. sp., were present in 1 of 8 timber rattlesnakes, Crotalus horridus. The narrow gamonts of H. sauritus are 15.0-19.0 x 3.5-5.0 microm, with LW 58-86 microm2 and L/W 3.2-4.7, with a narrow, rounded anterior end. The spherical to slightly ovoid oocysts produce ovoid to elongate sporocysts, 21-43 x 12-24 microm, L/W 1.20-2.7, containing on average 22.1 (10-34) sporozoites. This is the first report of a natural cross-familial transfer of a Hepatozoon species. Gamonts of H. horridus n. sp. are 13.0-17.0 x 4.0-6.0 microm, with LW 63-102 microm2 and L/W 2.6-4.0, and have broadly rounded ends. The gamont cytoplasm is vacuolated. The spherical to ovoid oocysts form spherical to elongate sporocysts 14-45 x 11-25 microm, L/W 1.0-2.3, producing an average of 13.0 (8-21) sporozoites. The salivary gland in 1 of 5 mosquitoes dissected contained 1 mature oocyst.     

Developmental stages of Hepatozoon hemprichii sp. nov. infecting the skink Scincus hemprichii and the tick Hyalomma impeltatum from Saudi Arabia

The life cycle of Hepatozoon hemprichi n. sp. is described; the vertebrate host is Scincus hemprichii and it is vectored by Hyalomma impeltatum. Erythrocytic stages of 18 ± 1.8 × 4 ± 0.8 μm developed in the hemocoel of ticks to sporozoites within 16-18 days. Schizogony occurred in the liver parenchyma and the endothelial cells of blood capillaries in lung and spleen. Mature schizonts measuring 27 ± 3.11 × 20.13 ± 3.0 μm produced 28 merozoites (on average). The merozoites were 13 ± 1.21 × 1.21 ± 0.72 μm with nuclei 5 ± 0.65 × 2.1 ± 0.51 μm. Syzygy and differentiation of gamonts took place in tick's hemocoel up to the third day post-infection (PI). The microgamont (16 ± 0.31 × 18 ± 0.42 μm) produced 4, uniflagellated microgametes at 4-5 days PI. The microgamete measured 15.2 ± 0.31 μm while the flagellum was always at least 26 μm. The macrogamete was very large in size (31 ± 3.11 μm) with a central nucleus. After fertilization, (5-6 days PI) zygotes developed into oocysts (55 ± 3.41 × 52 ± 4.11 μm) in which repeated mitotic divisions with centripetal invaginations occurred; each contained 18 banana-shaped sporozoites, 13.61 ± 0.8 × 1.2 ± 0.31 μm in size. Experimental transmission was successfully carried out by oral administration or by intra-peritoneal inoculation of the infective stages (sporozoites) to uninfected skinks and led to the appearance of blood stages after 5 wk and 4 wk, respectively.     

Two Plasmodium species of the crocodile skink Tribolonotus gracilis from Irian Jaya, Indonesia

Two undescribed Plasmodium species were present in 1 of 8 New Guinea skinks, Tribolonotus gracilis. Plasmodium tribolonoti n. sp. is characterized by rounded or oblong schizonts 6.1 x 5.3 microm (5-7 x 4-7) that produce on average 14.3 merozoites (10-21), in no particular arrangement of nuclei. All parasitized proerythrocytes and had no effect upon dimensions of host cells or their nuclei. Gametocytes, mostly erythrocytic, averaged 7.2 x 6.3 (6.5-9.0 x 5.5-7.5), with length x width (LW) 45.5 microm2 (38-63) and L/W 1.15 (1.0-1.5). Gametocytes are not sexually dimorphic in size or shape and had no effect upon dimensions of host erythrocytes or their nuclei. Schizonts of P. gracilis n. sp. averaged 4.3 x 3.5 (3-6 x 3-5), with 4.9 merozoites (3-8) usually arranged as a fan, and had no effect upon dimensions of host erythrocytes or their nuclei. Gametocytes averaged 5.9 x 5.5 (5.0-6.6 x 5.0-6.0), with LW 31.9 microm2 (25-40) and L/W 1.06 (1.0-1.2). Gametocytes are not sexually dimorphic in size or shape and had no effect upon dimensions of host erythrocytes or their nuclei.     

Rediscovery and redescription of Plasmodium pifanoi and description of two additional Plasmodium parasites of Venezuelan lizards

Plasmodium pifanoi Scorza and Dagert B., known only from the type host, Ameiva ameiva, is redescribed from Kentropyx calcarata collected in Territorio Amazonas, Venezuela. Schizonts, 6.2 x 4.5 (4-8 x 3-6), produce on average 11.9 (7-16) merozoites. Gametocytes average 12.4 x 6.0 (8-16 x 4-10), with length x width (LW) 72.9 (52-112) and L/W 2.18 (1.1-3.3), and always contain 1-5 prominent vacuoles. Macrogametocytes in active infection are longer than microgametocytes, with greater LW, but gametocytes in chronic infection are not sexually dimorphic in dimension and are slightly smaller. Two additional malarial parasites are described from K. calcarata. Plasmodium lepidoptiformis has small schizonts, 4.6 x 3.2 (3-6 x 2.5-3), that produce 5.1 (4-8) merozoites and commonly resemble a butterfly in appearance. Gametocytes are elongate, 9.0 x 4.3 (7-10 x 3-6), with LW 38.3 (24-51) and L/W 2.2 (1.3-3.3), and sexually dimorphic, with macrogametocytes longer than microgametocytes, with greater LW. Plasmodium minasense calcaratae is characterized by very small, usually fan-shaped, schizonts. 3.4 x 2.6 (2.5-4.5 x 2.0-3.0), that produce 3.9 (3-4) merozoites. Gametocytes are spherical or ovoid, 6.7 x 5.0 (4.5-9.0 x 3.0-7.0), with LW 33.7 (15-54) and L/W 1.4 (1.0-2.3), with no sexual dimorphism in dimensions.     

A new species of Eimeria (Apicomplexa: Eimeriidae) from the eastern pipistrelle, Perimyotis subflavus (Chiroptera: Vespertilionidae), in Arkansas

During November 2009 and March 2010, 20 adult eastern pipistrelles, Perimyotis (= Pipistrellus) subflavus, were collected from Polk County, Arkansas, and their feces were examined for coccidian parasites. Two (10%) of the bats were found to be passing oocysts of an undescribed species of Eimeria. Oocysts of Eimeria heidti n. sp. were ovoidal to ellipsoidal, 26.1 × 20.5 μm (23-31 × 18-23 μm), with a bilayered wall, externally rough, internally smooth, and with a shape index of 1.3. Micropyle and oocyst residuum were absent, but a subspherical polar granule was often present. Sporocysts were ovoidal, 13.0 × 8.8 μm (11-15 × 7-13 μm), the shape index was 1.6, a Stieda body was present and sub-Stieda and para-Stieda bodies were absent. A sporocyst residuum consisting of multiple globules dispersed along the perimeter of the sporocyst and between the sporozoites were present, sporozoites were elongate, with a subspherical anterior refractile body and elongate posterior refractile body; a nucleus not discernible. This is the second coccidian reported from this host and the fourth instance of a coccidian species reported from an Arkansas bat.     

A new species of <Emphasis Type="Italic">Hepatozoon</Emphasis> Miller, 1908 (Apicomplexa: Adelerina) from the snake <Emphasis Type="Italic">Philodryas nattereri</Emphasis> Steindachner (Squamata: Dipsadidae) in northeastern Brazil

Based on both unique morphological characteristics of the gamont, distinct changes caused to the host erythrocyte and analysis of partial 18S rRNA gene sequences, a new parasite of the genus Hepatozoon Miller, 1908 is described from the snake Philodryas nattereri Steindachner (Squamata: Dipsadidae) in northeastern Brazil. The new species, Hepatozoon musa n. sp., is characterized by large and curved mature gamonts (18.9 ± 0.9 μm in length and 3.8 ± 0.3 μm in width) that considerably engorge infected host erythrocytes and displace the nucleus laterally, which become longer and thinner. Phylogenetic estimates indicate the new species is more closely related to the recently described Hepatozoon cuestensis O’Dwyer, Moço, Paduan, Spenassatto, Silva & Ribolla, 2013, from Brazilian rattlesnakes. These recent findings highlight the need for further studies of Hepatozoon to better determine the biodiversity of this common but poorly-studied parasite group.     

A new Isospora species of passerines in the family Turdidae from Costa Rica

Seven thrush species (Turdidae) from Costa Rica were examined for intestinal parasites; 21 of the 84 (25%) birds sampled were positive for a new species of Isospora. Oocysts of Isospora zorzali n. sp. have thin, smooth, double, and colorless walls; they measure 19.7 ± 1.5 μm × 18.6 ± 1.4 μm (16-24 μm × 15-21 μm), with an average length-width ratio of 1.1 μm. Sporocysts are ovoid, measure 8.5 ± 1.1 μm × 14.5 ± 1.7 μm (7-11 μm × 11-18 μm) with an average length-width ratio of 1.7 μm. A nipple-like stieda body continuous with the sporocyst wall is present, but no substieda body was observed. A sporocyst residuum consisting of large equal sized granules was observed either clumped together or diffusely. The sporocysts fill the entire oocysts with little to no open space observed. This is the first report of Isospora species from any of the sampled host species and also the first report from any species of thrush in Costa Rica.     

Two new species of Isospora Schneider, 1881 (Apicomplexa: Eimeriidae) from the flap-necked chameleon Chamaeleo dilepis (Sauria: Chamaeleonidae) in the Republic of Namibia

Two new species of Isospora Schneider, 1881 from flap-necked chameleons Chamaeleo dilepis Leach are described from the faeces of specimens collected in the Republic of Namibia. O?cysts of Isospora freedi n. sp. from one of four (25%) C. dilepis collected in the East Caprivi District are spherical to subspherical, with a smooth, colourless, bilayered wall, measure 23.7?×?21.2?μm and have a length/width (L/W) ratio of 1.1. The micropyle and the o?cyst residuum are absent but a polar granule is sometimes present. Sporocysts are ovoidal to ellipsoidal and 13.9?×?10.3?μm in size with prominent Stieda and sub-Stieda bodies; and the sporocyst residuum is composed of a compact mass of large globules. The sporozoites contain anterior and posterior refractile bodies with a nucleus between them. O?cysts of Isopora mandelai n. sp. from three of seven (43%) C. dilepis collected in the Outjo District are ellipsoidal to cylindroidal, with a smooth, colourless, bilayered wall, measure 36.9?×?31.0?μm and have an L/W ratio of 1.2. The micropyle, o?cyst residuum and polar granule are absent. Sporocysts are ovoidal to ellipsoidal, 15.3?×?11.1?μm in size and contain Stieda and sub-Stieda bodies; and the non-membranous sporocyst residuum is composed of granules of various sizes. The sporozoites contain anterior and posterior refractile bodies with a nucleus between them. These two new taxa represent the third and fourth coccidian species reported from C. dilepis.     

A Haemocystidium species from the East African gecko Lygodactylus capensis grotei

Haemocystidium lygodactyli n. sp. parasitizes Lygodactylus capensis grotei (Gekkonidae) in Tanzania. Mature gametocytes in acute phase of infection average 16.3 x 5.7 microm (11-20 x 4-9.5 microm), with LW 93.0 (62-140 microm2) and L/W ratio 2.94 (1.2-3.9). Gametocytes usually lateral, lateropolar, or halteridial in position. There was no significant sexual dimorphism in gametocyte dimensions. Nuclei discrete in both sexes at maturity, with a rounded nucleolus usually present in microgametocytes. In chronic infection, gametocytes were 18.1 x 8.7 microm (8-25 x 5-11 microm), with LW 156.8 microm2 (80-250) and L/W 2.16 (1.1-3.6). When gametocytes from the chronic infection were compared with the same sex in acute infection, length did not differ, but differences were present between the same sex in each comparison of width, LW, and L/W. Macrogametocytes and microgametocytes in chronic phase were broader, larger, and less elongate and most commonly halteridial. Meronts were found only in endothelium and connective tissue of lung. Elongate to oval in shape, the larger meronts filled with nuclei were 12.2 x 6.9 microm (10.0 x 5.0-16.0 x 9.0), with LW 50-144 microm2 (85.1). In 1 initial infection followed for 49 days, apparently mature gametocytes appeared by day 28 postcapture. Binucleate parasites were present from day 14 throughout the course of infection, with their frequency increasing from 5% of immature parasites to 34% of mature gametocytes. Binucleate mature gametocytes were found in 1 other infection, where 14% had 2 nuclei. Sex ratio varied from 51 to 63% in favor of macrogametocytes.     

Morphologic and morphometric analysis of Hepatozoon spp. (Apicomplexa,Hepatozoidae) of snakes

Hepatozoon species are the most abundant hemoparasites of snakes. Its identification has been based mainly on the morphologic characterization of the gamonts in the peripheral blood of the vertebrate host and also of the cysts found in the internal organs of the vertebrate and invertebrate hosts. Using a computerized image analysis system, we studied five species of Hepatozoon from recently captured snakes in Botucatu, State of S o Paulo, Brazil, to evaluate the importance of the morphology and morphometry of the gamonts for the characterization of Hepatozoon species and to analyze the morphologic changes induced in the erythrocytes by the parasite. The studied species were H. terzii of Boa constrictor amarali, Hepatozoon sp. of Crotalus durissusterrificus, H. philodryasi of Philodryas patagoniensis, and H. migonei and H. cyclagrasi of Hydrodynastes gigas. We observed three different groups, one of them including the species H. terzii, H. philodryasi and Hepatozoon sp. of C. durissus terrificus; and the other two consisting of H. migonei and H. cyclagrasi. Degree of alterations in the erythrocytes was variable and it may be useful for characterization of Hepatozoon species.     

Phylogenetic relationships among Hepatozoon species from snakes, frogs and mosquitoes of Ontario, Canada, determined by ITS-1 nucleotide sequences and life-cycle, morphological and developmental characteristics

The molecular biological characteristics of Hepatozoon species infecting various species of snakes, frogs and mosquitoes were investigated by determining the nucleotide sequences of the first internal transcribed spacer region. A phylogenetic analysis was performed on seven isolates of Hepatozoon infecting snakes, including Hepatozoon sipedon and four morphologically similar but not identical forms, and two isolates of Hepatozoon catesbianae infecting Green frogs (Rana clamitans melanota). This analysis, which utilised data from first internal transcribed spacer nucleotide sequences, morphological and morphometric features of gamonts, oocysts and sporocysts, and previously determined life-cycle and host-specificity characteristics, revealed that H. sipedon is a polymorphic species with a wide host and geographic range. Four synapomorphies. including two nucleotide substitutions and two morphological character state changes, supported a monophyletic group of six isolates of H. sipedon from the central region of Ontario which was the sister group for an isolate (HW1) from the southern part of the province. Based on the results of this study, an evaluation of which criteria are useful for describing species of Hepatozoon is presented, with the intent of curtailing the practice of naming species based on morphological features of gamonts or on incomplete life-cycle data.     

Hepatozoon sauritus: a polytopic hemogregarine of three genera and four species of snakes in north Florida, with specific identity verified from genome analysis

Hemogregarines from Thamnophis s. sirtalis, Coluber constrictor priapus, Elaphe obsoleta quadrivittata, and E. g. guttara in northern Florida appeared to be conspecific on the basis of similar gamonts from all the hosts and sporogonic stages obtained from 3 hosts. The resemblance of gamonts to those of Hepatozoon sauritus, described from T. sauritus sackenii in southern Florida, justified comparison of DNA isolates from the type infection of H. sauritus with samples from each of the northern Florida hosts and with a morphologically distinct species, H. sirtalis, from northern Florida. A nucleotide sequence (530 bp) alignment of the 18S ribosomal RNA gene revealed 2 hemogregarine haplotypes that varied at 15 sites (p distance = 2.8%), which included 10 transitions and 5 transversions. Two well-supported clusters (100% bootstrap support) were revealed by a neighbor-joining tree topology. One cluster included the type infection of H. sauritus and all 4 of the other samples from the northern Florida hosts, with samples of H. sirtalis comprising a second cluster. Hepatozoon sauritus, therefore, is a polytopic species in contrast to the 8 other Hepatozoon species thus far described from snakes in Florida, each of which appears to parasitize a single host species.     

Species of coccidia (Apicomplexa: Eimeriidae) in shrews from Alaska, U.S.A., and northeastern Siberia, Russia, with description of two new species

Fecal samples (n = 636) from 10 species of shrews collected in Alaska (n = 540) and northeastern Siberia (n = 96) were examined for the presence of coccidia (Apicomplexa: Eimeriidae). Five distinct oocyst morphotypes were observed. Three types were consistent with oocysts of previously recognized coccidia species from other shrew hosts. These were Eimeria inyoni, E. vagrantis, and Isospora brevicauda, originally described from the inyo shrew (Sorex tenellus), dusky shrew (S. monticolus), and northern short-tailed shrew (Blarina brevicauda), respectively. We found 5 new host records for E. inyoni, 3 for E. vagrantis, and 3 for I. brevicauda. The 2 additional oocyst morphotypes, both from the tundra shrew (Sorex tundrensis), are putative new species. Sporulated oocysts of Eimeria beringiacea n. sp. are subspheroidal, 17.7 x 15.6 microm (14-24 x 13-20 microm) with a length (L)/width (W) ratio of 1.1 (1.0-1.4); these lack a micropyle (M), an oocyst residuum (OR), and a polar granule (PG). Sporocysts are ellipsoidal, 10.3 x 6.1 microm (7-14 x 4-8 microm), with a L/W ratio of 1.7 (1.3-2.3) and have a Stieda body (SB), Substieda body (SSB), and sporocyst residuum (SR). Oocysts of Eimeria tundraensis n. sp. are spheroidal to subspheroidal, 24.8 x 23.5 microm (23-26 x 22-25 microm), with a L/W ratio of 1.1 (1.0-1.2); these lack a M and OR, but a single PG is present. Sporocysts are elongate ellipsoidal, 15.4 x 8.3 microm (13-17 x 7-9 microm), with a L/W ratio of 1.9 (1.4-2.1) and have a SB, SSB, and SR.     

Two new eimerians (Apicomplexa) from insectivorous mammals in Madagascar

Fecal samples from 126 insectivorous mammals in Madagascar were collected between spring 1999 and fall 2001. In the Afrosoricida, 21 species in 5 genera were sampled, including 17 species of Microgale (31/96, 32% infected), Hemicentetes semispinosus (1/2, 50%), Oryzorictes hova (1/5, 20%), Setifer setosus (8/13, 61.5%), and Tenrec ecaudatus (5/8, 62.5%); in the Soricomorpha, only Suncus murinus was examined and 1/2 (50%) were infected. Two morphotypes of eimeriid oocysts, representing 2 presumptive new species, were found in 47 (37%) infected animals; only 2 afrosoricid hosts (2% of all hosts, 4% of infected hosts) had both oocyst morphotypes. Sporulated oocysts of the first morphotype, Eimeria tenrececaudata n. sp., are subspheroidal, 18.8 × 17.4 (17-22 × 15-20), with a length∶width ratio (L/W) of 1.1 (1.0-1.2); they lack a micropyle but may contain 0-2 polar granules and a single, small round oocyst residuum, 3 × 2.3. Sporocysts are lemon-shaped, 9.9 × 6.6 (9-11 × 5-8), with a L/W of 1.5 (1.2-2.0); they have a prominent, slightly flattened Stieda body and a substieda body but lack a parastieda body. The sporocyst residuum consists of only a few granules between the sporozoites, which are sausage-shaped and have a large posterior refractile body. Oocysts of the second morphotype, Eimeria setifersetosa n. sp. are spheroidal to subspheroidal, 30.1 × 28.6 (27-34 × 25-34), with a L/W of 1.1 (1.0-1.2); they lack both micropyle and oocyst residuum, but 1-2 polar granules are usually present. Sporocysts are subspheroidal to broadly ellipsoidal, 9.6 × 7.3 (9-11 × 6-8), with a L/W of 1.3 (1.1-1.7); they have a broad Stieda body, lack sub- and parastieda bodies, and have a residuum of a few granules scattered throughout the sporocyst. Sporozoites were not clearly defined, but what seemed to be a single large refractile body is seen, presumably in each sporozoite.     

Phylogenetic analysis of the genus Hepatozoon Miller, 1908 (Apicomplexa: Adeleorina)

A phylogenetic analysis of species of Hepatozoon Miller, 1908 was performed using 16 morphological, morphometric and developmental characters. An adeleorin parasite of gastropod molluscs, Klossia helicina Schneider, 1875 and four haemogregarines of other genera, Karyolysus lacertae (Danilewsky, 1886), Cyrilia lignieresi (Laveran, 1906), Desseria myoxocephali (Fantham, Porter & Richardson, 1942) and Haemogregarina balli Paterson & Desser, 1976 were used as the outgroup to 12 species of Hepatozoon. A single most parsimonious interpretation of the data was found, with the resulting cladogram having 28 transformations and a consistency index of 0.75. The proposed phylogeny revealed Hepatozoon as a paraphyletic group. One monophyletic lineage contained 10 of the 12 species of Hepatozoon, including all of those species that undergo gametogenesis and sporogony in the haemocoel of arthropods. Within this lineage, gamonts of those species found in vertebrate leucocytes instead of erythrocytes formed a clade basal to the remainder of the species. Species of Hepatozoon which undergo gametogenesis and sporogonic development in the gut epithelium of acarines, and which produce aflagellate microgametes, as well as the four outgroup taxa of haemogregarines, formed a monophyletic group and were the sister group to the remainder of the species of Hepatozoon. The biological and morphological diversity of these parasites suggests that species of the genus Hepatozoon, which are members of the paraphyletic haemogregarine complex, could be partitioned into at least two genera of adeleorin parasites.     

中国滑刃属一新种记述(滑刃目,滑刃科)

2001～2002年从山东省青州市韭菜Allium tuberosum的根际土壤中发现滑刃属Aphelenchoides1新种,定名为韭菜滑刃线虫Aphelenchoides alliussp.nov.。该虫具有以下特征:虫体大型;唇区缢缩,口针较长,无口针基部球;侧区具有6条侧线;生殖系统发育良好,卵巢具1～2个转折,卵母细胞单列;尾细锥形,末端收缩呈细指状,平截,刺状尾尖突生于其上;雄虫常见,尾钩状,末端具刺状尾尖突,交合刺典型,顶尖和喙突明显。已报道种中有8个种与新种相似,其中5个种虫体体长较短,小于500μm,易与新种分开,它们是:细尖滑刃线虫A.conimucronatus(L=280～440μm),高头滑刃线虫A.editocaputis(L=270～320μm),高山滑刃线虫A.montanus(L=390～400μm),稀少滑刃线虫A.rarus(L=300～320μm),沃恩滑刃线虫A.vaughani(L=360～430μm)。另3个种与新种相比较:中心滑刃线虫A.centralis侧线4条,尾巴较长,雄虫不常见;陶比恰滑刃线虫A.daubichaensis侧线4条,口针较短且有小的基部球,后阴子宫囊较短,卵巢无转折;一点红滑刃线虫A.emiliae口针基部球发达,中食道球椭圆形,更大19μm×15μm,后阴子宫囊较短。     

Antigenic analysis of gamonts of Hepatozoon canis purified from leukocytes

Hepatozoon canis is a tick-borne apicomplexan parasite of dogs that infects neutrophils and parenchymal tissues. To study the antigenic characteristics of this parasite, a technique was devised for the purification of gamonts from peripheral blood neutrophils. White blood cells were separated on Ficoll-Hypaque density gradients and the gamonts were released from the host neutrophils by nitrogen cavitation. The blood used for purification originated from dogs with natural or experimental infections of H. canis with a parasitemia of 1.4-33%. The number of parasites collected ranged from 1.5 X 10(6) to 4.2 X 10(7). Portions of purified gamonts were separated and examined under phase and scanning electron microscopy, and the remaining purified parasites were then used as a source of antigens to characterize the humoral immune response by western blot analysis. Serum antibodies from infected dogs recognized more than 15 gamont antigens, and the antigenic patterns observed with sera from naturally and experimentally infected dogs were nearly similar. Four immunodominant protein bands of relative molecular weights of 107, 88, 63, and 28 kDa were recognized by all of the sera examined. The technique applied here for the isolation of host cell-free gamonts will facilitate studies on antigenic composition and immune responses against H. canis and on antigenic relationships between Hepatozoon from different host species and geographic regions.