Soichi Imai

The Occurrence and Ape-to-Ape Transmission of the Entodiniomorphid Ciliate Troglodytella abrassarti in Captive Gorillas

ABSTRACT. Entodiniomorphid ciliates are often present in the colons of wild apes. In captive apes the infection tends to gradually disappear, with the exception of Troglodytella abrassarti. We used fecal examinations to screen the gorillas (Gorilla gorilla gorilla) in European (Czech Republic, UK) and Australian Zoos to explore the ape‐to‐ape transmission pattern of T. abrassarti. Gorillas from two out of three European Zoos were positive for T. abrassarti, while gorillas from the Australian Zoo were negative. We documented a horizontal transmission of T. abrassarti to a non‐infected adult gorilla introduced into a Troglodytella‐positive group in the Prague Zoo and traced the origin of the ciliate infection to the Paignton Zoo (UK) using serial fecal examinations. During this study, two infant gorillas born in the Prague Zoo (CZ) first became positive for T. abrassarti at the age of 9 mo. Ciliate morphology and the sequencing of the small subunit rRNA gene and the internal transcribed spacer rDNA spacer region revealed that T. abrassarti affects both captive gorillas and chimpanzees. We conclude that zoo transport plays a major role in the distribution of T. abrassarti among captive gorillas.

Infraciliary bands in the rumen ophryoscolecid ciliate Ostracodinium gracile (Dogiel, 1925), observed by light microscopy.

ABSTRACT Morphological features of the rumen ciliate Ostracodinium gracile (Dogiel, 1925) are described from pyridinated silver carbonate‐impregnated specimens. Ostracodinium gracile has a characteristic arrangement of infraciliary bands not present in other ophryoscolecid ciliates. Buccal infraciliature is composed of three polybrachykineties. The adoral polybrachykinety does not completely encircle the circumference of the vestibular opening, but arches ventrally from its right to left side. The dorsoadoral polybrachykinety extends laterally along the dorsal side of the vestibular opening. The vestibular polybrachykinety extends along the dorsal wall of the long tubular vestibulum. Dorsal infraciliature consists of the dorsal polybrachykinety that extends laterally along the dorsal side of the body. During binary fission, four primordia, that is ventral, right, left, and dorsal primordia, form in the stomatogenic field and develop into the adoral, dorsoadoral, vestibular, and dorsal polybrachykineties of the opisthe. respectively.

A new entodiniomorphid ciliate, Troglocorys cava n. g., n. sp., from the wild eastern chimpanzee (Pan troglodytes schweinfurthii) from Uganda.

ABSTRACT. Troglocorys cava n. g., n. sp. is described from the feces of wild eastern chimpanzee, Pan troglodytes schweinfurthii, in Uganda. This new species has a spherical body with a frontal lobe, a long vestibulum, a cytoproct located at the posterior dorsal side of the body, an ovoid macronucleus, a contractile vacuole near the cytoproct, and a large concavity on the left surface of the body. Buccal ciliature is non‐retractable and consists of three ciliary zones: an adoral zone surrounding the vestibular opening, a dorso‐adoral zone extending transversely at the basis of the frontal lobe, and a vestibular zone longitudinally extending in a gently spiral curve to line the surface of the vestibulum. Two non‐retractable somatic ciliary zones comprise arches over the body surface: a short dorsal ciliary arch extending transversely at the basis of the frontal lobe and a wide C‐shaped left ciliary arch in the left concavity. Because of the presence of three ciliary zones in the non‐retractable buccal ciliature, the present genus might be a member of the family Blepharocorythidae, but the large left concavity and the C‐shaped left ciliary arch are unique, such structures have never been described from other blepharocorythids.

Descriptions of new Parentodinium ciliates in the family Parentodiniidae n. fam. from Hippopotamus amphibiusin comparison with some entodiniomorphs from horses and cattle

Descriptions of Parentodinium ostrea Thurston & Noirot-Timothee, 1973 and P. africanum Thurston & Noirot-Timothee, 1973 are revised on the basis of observation by pyridinated silver carbonate impregnation. Two new species, Parentodinium pediculum n. sp. and P. lituus n. sp., are also described. Based on the presence of caudal lobes, P. ostrea is divided into three forms, f. ostrea Thurston & Noirot-Timothee, 1973, f. euostrea n. f., and f. ablobum n. f. and P. pediculum is divided into two forms, f. pediculum n. f. and f. dorsale n. f. Until now, Parentodinium has been included in the family Cycloposthiidae. Because of its characteristic arrangement of infraciliary bands, a new family Parentodiniidae is proposed. Parentodinium ciliates are compared with five entodiniomorphid ciliates, Bundleia postciliata, Blepharocorys valvata, and Cycloposthium bipalmatum from the intestine of horses and Entodinium simplexand Eudiplodinium maggii from the rumen of cattle. Parentodinium has characteristic features intermediate between other entodiniomorphid families in both general and infraciliary morphology. Parentodinium has an ovoidal body laterally compressed, an ovoidal macronucleus varying in location, a micronucleus adhering to various sides of the macronucleus, and a single contractile vacuole in a posterior ventral location. Parentodium ostrea, P. africanum and P. pediculum have a cytoproctal ciliary tuft. Parentodinium has a characteristic arrangement of infraciliary bands distinct from other entodiniomorphid ciliates. The adoral polybrachykinety completely encircles the circumference of the vestibular opening. There are several vestibular kineties extending along the dorsal wall of the tubular vestibulum. Paralabial kineties are located at the right ventral side of the adoral polybrachykinety. Cytoproctal kineties run inside the cytoproct.

Entodiniomorphid ciliates from the wild lowland gorilla with the description of a new genus and three new species.

The entodiniomorphid ciliates in gorilla in Gabon, West Africa, were surveyed and observed by light and scanning electron microscopy. As a result, 4 species belonging to the families Troglodytellidae and Cycloposthiidae were identified, and 3 of them were new to science. These species were described as Goriliophilus thoracatus n.g., n.sp., Troglodytella gabonensis n.sp., and Prototapirella gorillae n.sp. SEM observations of Goriliophilus and Troglodytella revealed in particular the surface structures of somatic ciliary bands in which the cilia extended as rectangular tufts from uniformly distributed basements, smooth-surfaced anterior cap, armature-like ridges, and the presence of a left-ventral groove. From the similarity and difference of the morphology among these species, their phylogenetical relationships were discussed.

Trichodinid species from the gill of cultured Japanese eel, Anguilla japonica, with the description of a new species based on light and scanning electron microscopy.

Trichodinid ciliates infested on the gills of cultured Japanese eels, Anguilla japonica, were surveyed. A new species was detected in addition to Trichodina jadranica and T. acuta, and was described as T. japonica n.sp. Scanning electron microscopic observations on the new species revealed an aboral ciliary complex which consisted of long and sparsely arranged marginal cilia, a basal ciliary ring having very short cilia, and a well developed locomotor wreath. A thin anterior septum existed between the marginal ciliary ring and the locomotor ciliary wreath, and a thicker basal septum was observed between the locomotor ciliary wreath and the basal ciliary ring. On the adhesive disc, denticles and radial pins were clearly observed by scanning electron microscopy. The basal membrane, which forms the periphery of the adhesive disc, consisted of three layers. A dented ring caused by attachment of T. japonica was observed on the gill surface of the eel examined.

Ciliate protozoa in the rumen of sassaby antelope, Damaliscus lunatus lunatus, including the description of a new species and form.

ABSTRACT. Composition of rumen ciliate fauna in five Zambian, sassaby antelopes was determined. Six genera, 18 species, and four forms were identified. One new species and form, belonging to the subfamily Diplodiniinae, were found, then labeled Ostracodinium damaliscus n. sp. and Diplodinium bubalidis f. aspinosum n. f., respectively. Only ophryoscolecid species were present while isotrichids were absent. Twelve of 18 total species are commmonly found in African antelopes. Three of those 12 species, Entodinium fyferi, Enoploplastron garstangi and Opisthotrichum janus, are only found in African antelopes. Percentage composition was low in the genera ml of rumen fluid, and the average number of ciliate species per host was 17.2.

Ciliates from the cecum of capybara (Hydrochoerus hydrochaeris) in Bolivia. 2. The family Cycloposthiidae.

Summary Cycloposthiid ciliates in the cecum of five capybaras in Bolivia were surveyed and their morphology and infraciliature was studied using silver impregnation techniques. A new Monoposthium species, M. cynodontum n. sp., a new Cycloposthium species, C. bursa n. sp., and nine known Cycloposthium species, C. incurvum Cunha, 1915 , C. hydrochoeri Cunha, 1915 , C. lenticularis Hollande & Batisse, 1959 , C. minutum Cunha & Muniz, 1927 , C. compressum Cunha, 1915 , C. elongatum Hollande & Batisse, 1959 , C. caudatum Cunha & Muniz, 1927 , C. cristatum Cunha & Muniz 1927 , in the family Cycloposthiidae, were described. Both density and diversity of the ciliate faunae were extremely high: average values of ciliate density, Brillouin’s diversity index, number of species per host and equitability were 240.0 x 104/ml, 2.307,22.4, 74.2%, respectively.

Redescription of Triplumaria selenica Latteur et al., 1970 (Ciliophora, Entodiniomorphida) and its phylogenetic position based on the infraciliary bands and 18SSU rRNA gene sequence

Triplumaria selenicaLatteur, Tuffrau and Wespes, 1970 was redescribed from pyridinated silver carbonate-impregnated specimens. Triplumaria selenica has a slit of the vestibular opening extending posteriorly along the left side of the vestibulum. The wide C-shaped adoral polybrachykinety extends along the ventral side of the vestibular opening. The narrow perivestibular polybrachykinety extends laterally along the dorsal side of the vestibular opening from the right end of the adoral polybrachykinety and forms a loop extending posteriorly along the vestibular slit to join to the left end of the adoral polybrachykinety. The 18SSU rRNA gene of T. selenica as well as those of six other entodiniomorphid species, Raabena bella, Blepharocorys curvigula, Entodinium longinucleatum, Eudiplodinium rostratum, Metadinium medium, and Ostracodinium gracile was sequenced. The neighbor joining and maximum parsimony phylogenetic trees were constructed to discuss the evolution of entodiniomorphs. Our results will support and extend Wolskas hypothesis: the ancestral forms of blepharocorythids have evolved into ophryoscolecids and Cycloposthium species via the ancestor of Triplumaria.

Light Microscopical Observation of Infraciliary Bands of Eodinium posterovesiculatum in Comparison with Entodinium bursa and Diplodinium dentatum

Abstract Morphological features of the four morphotypes of the rumen ciliate, Eodinium posterovesiculatum, are described from pyridinated silver carbonate-impregnated specimens. Infraciliary bands are compared with those of Entodinium bursa and Diplodinium dentatum. In Entodinium bursa, the adoral polybrachykinety is “C” shaped and the vestibular polybrachykinety extends from the dorsal extremity of the adoral polybrachykinety as in other Entodinium species. In Diplodinium dentatum, the adoral polybrachykinety encircles most of the circumference of the vestibular opening and the vestibular polybrachykinety extends from the inner side of the adoral polybrachykinety as in other Diplodinium species. Infraciliary bands in Eodinium posterovesiculatum encircle the whole circumference of the vestibular opening and are, therefore, distinct from Entodinium, Diplodinium and other ciliates in the family Ophryoscolecidae. In Eodinium posterovesiculatum, the adoral polybrachykinety and the anterior part of the vestibular polybrachykinety encircle the vestibular opening. The wide and long vestibular polybrachykinety extends along the right wall of the tubular vestibulum and is bordered by a kinety. Kinetids in the central part of the vestibular polybrachykinety are randomly disposed. The genus Eodinium is valid because of this characteristic polybrachykinety arrangement in Eodinium posterovesiculatum.