Surface ultrastructure of the tegument of Clonorchis sinensis newly excysted juveniles and adult worms.

The tegumental structures of newly excysted juveniles and adult worms of Clonorchis sinensis were studied using scanning and transmission electron microscopy. After excystation the juvenile's tegumental surface is characterized by knoblike protuberances and is armed almost entirely with numerous rows of small spines encircling the body. These spines are double- or triple-pointed on the anterior portion of the body and become single-pointed posteriorly. Four types of presumed sensory structures were observed as follow: A) ciliated knoblike papillae and B) nonciliated platelike papillae, both of which are arranged in rougly a bilaterally symmetrical pattern dorsally, ventrally, and laterally; C) rounded swellings of nonciliated papillae on the lips of the ventral and oral suckers, which are characterized in the transmission electron microscope by a rounded dense body in the apical bulb; and D) a sensory receptor with a bulbous projection having the appearance of a modified cilium, which was not found with SEM likely owing to its being enclosed by an extension of the tegument. In full-grown adult worms, the tegumental surface is knobbed or lobulated in various forms without surface spines. The tegumental structures in the adults appear to be clearly differentiated from those in the juveniles. Upraised, buttonlike papillae, each topped by a short cilium, which are similar to the Type A papillae in the juveniles, are distributed thickly around the oral and ventral suckers, and are rather randomly scattered over the remainder of the body. Some nonciliated swollen papillae were found on the lip of the ventral sucker.     

日本棘隙吸虫体被超微结构的研究

本文报道扫描电镜观察下日本棘隙吸虫皮式、体棘和3种感觉乳突的形态和分布。     

Nutlet micro‐morphology of the genus Microula (Boraginaceae) from the Qinghai–Tibetan Plateau,and its systematic implications

The micro‐morphology of nutlets in 30 taxa (28 species and 2 varieties) of Microula Benth. (Boraginaceae) was surveyed by light and scanning electron microscopy. A principal coordinate‐based ordination analysis (PCO) (8 morphological and 14 micro‐morphological characters) was applied to explore whether taxa clustered according to the current sectional taxonomy. The nutlet epidermis showed three major features: trichomes, papillae and lamellae. Two basic trichome types could be identified: branched and unbranched. Stellate trichomes (STT) and stipitate stellate trichomes (SST) can be considered as two subtypes of branched trichomes based on shape and branching location. Three kinds of unbranched trichomes were recognized by their shapes: slender trichomes (SLT), spear‐like trichomes (SPT) and conical trichomes (CT). Four types of papillae were revealed in this genus: central apiculate papillae (CAP), debris‐covered convex papillae (DCP), rugous papillae (RP) and tabular papillae (TP). The lamellae was classified in five types: glossy lamellae (GL), thread‐like lamellae (TL), rugous lamellae (RL), interrupted lamellae (IL) and debris‐covered lamellae (DCL). The variation in the nature of surface sculpturing, nutlet shape and size, dorsal aperture shape, and attachment scar positions proved useful diagnostic characters. Taxa belonging to the same section generally clustered together in the PCO analysis. A key based on the morphology and micro‐morphology of nutlets is provided to distinguish the sections of Microula. The presence of SLT, STT, DCP and DCL is consistent with the macro‐morphological classification and provides additional evidence for the subgeneric delimitations. The SST, SLT, CAP, DCP, RP, DCL, GL and RL are useful in discriminating species in Microula. Additionally, the distribution of some trichomes, papillae and lamellae types is correlated with the altitudinal distribution of the species.     

A new species of Allocreadium (Trematoda: Allocreadiidae) from freshwater fishes in the Danjiangkou Reservoir in China

A new species of Allocreadium, Allocreadium danjiangensis n. sp., is described from the intestine of several species of freshwater fish, including Abbottina rivularis (Basilewsky, 1855), Sarcocheilichthys nigripinnis nigripinns (Güther, 1873), Gnathopogon argentatus (Sauvage et Dabry 1874), Opsariichthys uncirostris bidens (Gunther, 1873), and Erythroculter mongolicus mongolicus (Basilewsky, 1855) (Cyprinidae) from the Danjiangkou Reservoir in central China. The main morphological characters of the new species are as follows: vitelline follicles numerous, extending from the level of acetabulum to posterior extremity, distributed over both sides around the ceca; cirrus sac relatively large, developed, lying obliquely anterior to the acetabulum, extending from the level of the intestinal bifurcation to the central level of acetabulum, and overlapping left or right cecal; and ovary much smaller than testes, generally close to or even overlapping the anterior border of anterior testis. Observation by scanning electron microscopy shows only 2 kinds of tegumental formations, i.e., papillae and tubercles, instead of 3 types of tegumental formations, i.e., papillae, bosses, and minute sensor receptors observed on other species of the Allocreadiidae. The tegumental striations of the present species vary on the different parts of the body. In addition, a new structure, identified as the "groove" with a tonguelike tubercle, was observed on the inner wall of acetabulum.     

Ultrastructure of the ventral sucker of Schistosoma mansoni cercaria

The ventral sucker of Schistosoma mansoni cercaria is a cupshaped structure that is attached to the ventral surface of the organism by a homogeneous connective tissue that surrounds the acetabular glands. The sucker consists of an extensive complex of circular and longitudinal muscles. The longitudinal muscles extend outwoard in a radial pattern to form the cup of the organ. Intermingled with the muscles are nerve bundles and subtegumental cells (cytons). Dendritic nerve fibers connect to sensory papillae which are found on the surface tegument. Two types of sensory papillae are present: a commonly found unsheathed uniciliated papilla, and a previously unidentified tegumental encapsulated structure. Tegument with spines covers the ventral sucker, although the tegumental encapsulated sensory papilla lacks spines. © 1995 Wiley-Liss, Inc.     

A Redescription of Adult Phyllodistomum umblae (Fabricius) (Digenea, Gorgoderidae) from Salvelinus alpinus (L.) in Norway

Phyllodistomum umblae (Fabricius, 1780), originally described on the basis of specimens recovered from the ureter of Arctic char Salvelinus alpinus in Drangedalen, Norway, is here redescribed with both light (LM) and scanning electron microscope (SEM) from material obtained from the type host and type locality. This species has been overlooked in general text-books of this century, e.g. those of Dawes and Yamaguti, but was discussed by Nybelin in a paper in 1926 in which he suggested its conspecificity with P. conostomum Olsson. The dimensions, shapes, position and arrangement of the internal structures and selected size ratios are described and illustrated with LM-pictures. The SEM-investigation reveals the tegumental microstructure, and special emphasis is given to the arrangement of papillae. The body papillae comprise: (a) constant numbers in a constant bilateral arrangement; (b) a variable number in an orientated bilateral concentration called rows; (c) regional concentrations; (d) randomly distributed ones. This system and its variability are described and figured. Four types of papillae, and their distribution as seen by SEM, are described. These results are compared with the results from other SEM–investigations on gorgoderids.     

The ultrastructural characterization of the tegument of Clonorchis sinensis (Cobbold, 1875) cercaria.

The tegumental ultrastructure of the cercaria of the liver fluke, Clonorchis sinensis (Cobbold, 1875), was studied by scanning and transmission electron microscopy. The body surface is almost encircled by many rows of regularly arranged spines. The tegumental syncytium of the body contains many rod-shaped dense granules and central electron-lucent bodies, neither of which are present in the tail tegument. There are four rows of hooked teeth and modified spines on the oral cone. These teeth are differentiated morphologically and probably functionally from the other body spines. Disc-shaped papillae with long or short cilia are distributed on the body in a bilaterally symmetrical pattern dorsally and ventrally. There are 30 to 37 papillae with much longer cilia laterally. Four pairs of papillae were found on the tail. From their structure and location these papillae appear to have a mainly tango- or rheoreceptive function. Another type of sheathed papillae is situated around the oral sucker. The cuticular tegument is expanded laterally at the base of the tail, forming a characteristic sac-like structure.     

Tegumental ultrastructures of Echinoparyphium recurvatum according to developmental stages

The present study was performed to observe tegumental ultrastructure of Echinoparyphium recurvatum according to developmental stages. Worms (1, 3, 5 and 15-day old) were recovered from chicks experimentally infected with metacercariae from Radix auricularia coreana. One-day old worms were elongated and ventrally concave, and covered with peg-like tegumental spines except the adjacent areas of the head crown and excretory pore. Type I sensory papillae were distributed on the lip of the oral sucker, and grouped ciliated papillae were around the oral sucker. Peg-like tegumental spines were densely distributed on the anterior surface of the ventral sucker level. The ventral sucker had an aspinous tegument and no sensory papillae. Tegumental spines on the posterior surface of the ventral sucker level were sparsely distributed and disappeared posteriorly. In 3 and 5-day old worms, the tegument around the oral sucker was aspinose and wrinkled concentrically. The ventral sucker had a wrinkled tegument and many bulbous papillae. Type I sensory papillae were distributed between the bulbous papillae. Tegumental spines were spade-shaped with a terminal tip. A total of 45 collar spines including 4 end group ones on both ventral corners was alternately arranged in 2 rows. The 15-day old worms were very stout and their tegumental spines were tongue-shaped without a terminal tip. From the above results, it is confirmed that the surface ultrastructure of E. recurvatum was generally similar to that of other echinostomatid flukes. However, some features, i.e., morphological change of tegumental spines and appearance of sensory papillae on the ventral sucker according to development, and number, shape and arrangement of collar spines, were characteristic, which may be of taxonomic and bioecological significance.     

Scanning and transmission electron microscopical observations on the tegument of excysted metacercariae and adults of Zygocotyle lunata.

Scanning and transmission electron microscopical observations were made on the tegument of excysted metacercariae and adults of the paramphistome, Zygocotyle lunata (Digenea: Trematoda). In accord with other paramphistomes studied, this species lacks spines and mitochondria in the tegumentary syncytium and associated cytons. The newly excysted metacercarie, which possessed relatively few tegumental papillae, were cylindrical in comparison to adults which were distinctly flat. The adults had large numbers of tegumental papillae in the region of the oral sucker and acetabulum.     

Surface ultrastructure of the developmental stages of Heterophyopsis continua (Trematoda: Heterophyidae).

Ultrastructural observations were made on the tegument of juvenile and adult stages of Heterophyopsis continua using scanning electron microscopy. On the surface posterior to the ventral sucker, the tegumental processes were bandlike in the metacercariae, cobblestonelike in the flukes 2 days postinfection (PI), and velvety at 3 days PI. The anterior surface between the oral and ventral suckers of the metacercariae was packed densely with tegumental spines having a 10- to 14-pointed tip. In flukes 6 days PI, the number of points increased to 15-17. The tegumental spines immediately behind the ventral sucker on the metacercariae surface possessed 5-7 points; posteriorly the points were reduced in size and in number. Ciliate sensory papillae (type I), as single or clumped forms of 2 or 3, were abundant around the oral and ventral suckers of metacercaria and adult worms. The clumped papillae appeared bilaterally symmetrical on the dorsal and ventral surfaces. The ciliate papillae may function in tango-, rheo-, and/or chemoreception. On the lip of the ventral sucker, 6-7 aciliate domed papillae (type II) were arranged in an equidistant manner. At 2 days PI each type II papilla became a clumped form having 2 or 3 papillae. Type II papillae may function as tango- and/or pressure-receptors. The structure and distribution of papillae suggest that the ventral sucker likely functions as a holdfast organ and the oral sucker as a probing organ involved in feeding.     

Ultrastructural features of the tegumental surface of a new metacercaria, Nematostrigea sp. (Trematoda: Strigeidae), with a search for potential taxonomically informative characters

The tegumental surface of a new strigeid metacercaria, Nematostrigea sp., which is a parasite of the freshwater fish Channa gachua (Hamilton) in central Vietnam, is described for the first time using scanning (SEM) and transmission (TEM) electron microscopy. In addition to the general tegumental surface in various parts of the body, details of the surface of the suckers, lappets and holdfast organ are presented, as are variations in the form and distribution of the body spines. As good taxonomic criteria are few in diplostomoid metacercariae at both specific and generic levels, a number of the ultrastructural features revealed may prove to represent taxonomically informative characters. These include the presence of: two rings of dome-shaped papillae localised at different levels on the rim of the oral sucker, a single ring of ciliated papillae on the inner margin of the ventral sucker and a band of dome-shaped papillae along the lateral margins of the broad body-fold in the ventral forebody; an unarmed oral sucker and anteroventral surface of the forebody, although the latter bears protuberant secretory pores; an armed ventral sucker covered by six-pointed spines, except on its rim; multi-pointed spines along the dorsal and ventral sides of the forebody, with the number of their teeth increasing posteriorly; multi-pointed spines on the forebody which gradually transform into single-pointed, more widely distributed spines on the hindbody, disappearing completely at posterior end of the body; the surface of the lappets with a particular distribution of pores leading to three types of secretory glands and three topographical modifications (areas where the surface is smooth, bears digitiform processes or bears recurved, dagger-shaped spines); and the surface of the holdfast organ which is covered with densely packed, straight or slightly curved, simple spines on its lateral surface but is smooth medially.     

Micromorphology of Leaf Epidermis of Chimonobambusa (Bambusoideae)

Micromorphological characters of leaf epidermis of 27 published species of Chimonobambusa Makino were examined by both light and scanning electron microscopes (Table 1). On the adaxial surface, bulliform cells are of irregular or tetragonal shape and in 2-- 3 rows between veins; stomata rare. On the abaxial surface, intercostal long cells are of thin and sinuous wall; short cells solitary, paired, or 3 to several in a row on veins; silica bodies narrow tall or saddle like; bicellular hairs common, with the basal cell slightly longer than or as long as the distal cell; hooks elliptic and apiculate, common in some species and rare in the others; papillae numerous, those overarching stomata showing different patterns (Plates 1, 2). The examined species exhibit three types of leaf epidermis (Table 2 ): 1, papillae widely spread, 4 rod- like papillae overarching the individual stomata, hooks common, including all the six examined species of Sect. Qiongzhuea and 9 species of Sect. Oreocalamus; 2, papillae around stomata only (with the exception of C. microfloscula), the 4 papillae branched or curved, plus several small ones, forming an arciform cover over the individual stomata, hooks sparse, including 7 species of Sect. Oreocalamus and 1 species of Sect. Chimonobambusa; 3, papillae overarching stomata intermediate between the other two types, with the other characters similar to type 1, including 2 species of Sect. Chimonobambusa and 2 species of Sect. Oreocalamus. The three types more or less correspond to the current classification of the genus based on gross morphology, but since Sect. Oreocalamus showed all the three types and type 3 was somewhat intermediate between the other two, present data support a broad sense of the genus Chimonobambusa, and the three sections proposed by Ohrnberger (1990) are to some extent acceptable. The results support the removing of C. luzhiensis from Sect. Qiongzhuea, but reassignment of C. metuoensis to Sect. Qiongzhuea cannot be confirmed. In addition, the leaf epidermis is of diagnostic value at species level. The data support the inclusion of C. linearifolia in C. angustifolia, but do not support that of C. rivularis in C. lactistriata, nor of C. yunnanensis and C. tuberculata in C. armata (Ohrnberger, 1990). In fact, C. yunnanensis, C. tuberculata and C. lactistriata, in addition to C. hirtinoda, are similar to C. qudrangularis in both leaf and gross morphological characters; so is C. pachystachys to C. utilis, C. neopurpurea to C. marmorea, and maybe C. rigidula to C. szechuanensis. They are possibly sister-species.or even conspecific, respectively. The various specific papillate patterns are characteristic of bamboo taxa, andinvestigation of wider samples will be of great interest in bamboo systematics.     

Surface ultrastructure of Heterophyes nocens (Trematoda: Heterophyidae).

The surface ultrastructure of Heterophyes nocens (Trematoda: Heterophyidae) was studied by scanning electron microscopy(SEM). The adult worms were recovered from experimentally infected cats and from a naturally infected patient. They were leaf-like, ventrally concave, and ovoid or pyriform in shape. Ciliated knob-like sensory papillae (type I) were observed in single or grouped forms on and around the oral sucker, whereas non-ciliated round swellings (type II papillae) were seen on the lip of the ventral sucker. The tegumental spines around the oral sucker were 5-9 pointed, whereas those between the two suckers were 12-17 pointed. Ventrolaterally, three groups of 5-6 type I papillae were located between the oral and ventral suckers, with single ones alternating between them. The genital sucker was protruded or depressed, depending on the contraction state of the flukes, and the gonotyl spine number ranged 50-60. The number of tip points of tegumental spines was decreased posteriorly; finally they became 1-3 pointed. On the dorsal surface, 4 groups of 4-5 type I papillae were symmetrically located on both lateral sides, and the shape and distribution of tegumental spines were similar to those of the ventral surface. Although the tegumental ultrastructure of H. nocens was generally similar to those of other heterophyids, the genital sucker morphology including the number of gonotyl spines and/or the distribution pattern of tegumental spines and sensory papillae were suggested to be the characteristic features of H. nocens.     

异穗卷柏的显微与近红外光谱鉴定研究

对两种不同类型的异穗卷柏(Selaginella heterostachysBaker)药材的外观形态、孢子与茎的显微特征及近红外光谱特征进行了比较研究。结果表明:两类异穗卷柏的植株性状虽有明显不同,但其孢子形态、茎的解剖特征及近红外漫反射光谱特征一致。研究结果为异穗卷柏物种分类与药材鉴定提供了依据。     

Stigma characteristics and angiosperm taxonomy

When a classification based upon certain morphological and physiological characters of the stigma was applied to ca. 1,000 species of some 900 genera of angiosperms, several taxonomic regularities emerged. Most families proved to be relatively homogeneous in stigma type, whilst others were strikingly diverse. Among the latter were certain supposedly primitive families such as the Liliaceae, a fact that may have some phylogenetical significance. Sometimes where a family proved to be homogeneous in respect to the more general characters of the stigma, fuller investigation revealed great variation in detail. An example is given by the Boraginaceae, a family in which stigma characters are of potential taxonomic importance. The stigma papillae in this family are often capitate, with heavily cutinised heads, and pollen has to be inserted forcibly between the papillae. There is a strong correlation between pollen size and stigma–papilla size, so that certain types of cross pollination are impossible. These specialisations can thus play a part as isolating mechanisms. The form of the stigma papillae is probably also important in genera of the Boraginaceae adapted to arid conditions, since the contiguous cutinised caps overarch the actual receptive surfaces and so. presumably, offer protection from desiccation.
In both monocotyledons and dicotyledons, clear relationships exist between stigma type and physiology, and notably with the type of self–incompatibility system. It is already apparent that stigma characters can have predictive value in the investigation of breeding systems.
The paper includes a comprehensive literature list, covering most ot the principal sources of structural, taxonomic and other data bearing upon angiosperm stigmas.     

Megalodiscus temperatus: Scanning electron microscopy of the tegumental surfaces

The tegumental surface of Megalodiscus temperatus forms cobblestonelike areas with rows of indentations encircling the worm. This pattern merges in several areas into folds and ridges, some of which represent the musculature of the posterior sucker and genital pore. Papillae surrounding the base of the oral sucker appear as two types: one with a bulb-like base and a short apical knob; the second typified by a hair-like structure (cilium?) of variable length projecting from a pit. From their location on the oral sucker and the resemblance to previously described structures, they are presumed to be sensory receptors. A circle of papillae on the closed posterior sucker was also observed. Rod-shaped bacteria were seen adhering to some of the worms observed but they were not found to be in any special association with the tegument or in any specific areas of the worm's surface.     

Microtriches of tetraphyllidean metacestodes from Western Mediterranean striped dolphins (Stenella coeruleoalba)

The tegumental structures of two types of tetraphyllidean plerocercoids and two types of merocercoids (Phyllobothrium delphini and Monorygma grimaldii) from Mediterranean striped dolphins, Stenella coeruleoalba, are described for the first time using scanning electron microscopy. The tegument of all of the specimens was fully covered with microtriches. Four basic types were found: filitriches, blade-like spinitriches of different sizes and shapes, cone-shaped spinitriches (with two parallel small projections of equal length at the apex), and crowned cylindrical spinitriches (with 6-7 small papillae forming a crown at the apex); the two latter types are newly described. The two types of plerocercoids had a similar morphology and distribution of microtriches; in addition, cilium-like projections appeared interspersed among the microtriches on the apical sucker, accessory suckers, and distal bothridial loculus. Merocercoids exhibited a greater variety of tegumental structures, especially on the distal bothridial loculus. Both merocercoid types had regularly spaced papillae or "buttons" on the accessory suckers and the distal bothridial loculus that were composed of a central cilium-like projection surrounded by numerous filitriches. However, crowned cylindrical spinitriches were specific to P. delphini and cone-shaped spinitriches were specific to M. grimaldii. Differences in the morphology and distribution of scolex microtriches of adult cestodes have been considered useful for species identification. A previous molecular study has suggested that P. delphini and M. grimaldii are actually different congeneric species. Our study has shown that significant differences in the morphology and distribution of microtriches occur between these species at the merocercoid stage.     

The taxonomy of the family Paramphistomidae Fischoeder, 1901 with special reference to the morphology of species occurring in ruminants. VIII. The genera Stephanopharynx Fischoeder, 1901 and Balanorchis Fischoeder, 1901

Summary Only Stephanopharynx compactus Fischoeder, 1901 is considered valid under the genus Stephanopharynx Fischoeder, 1901 and S. secundus Stunkard, 1929 and S. coilos Dollfus, 1963 are regarded as its synonyms. The species is redescribed and illustrated based on new material and scanning electron photomicrographs of its tegumental surfaces and the internal surface of its pharyngeal pouch are provided. Balanorchis anastrophus Fischoeder, 1901, the one and only species of the genus Balanorchis Fischoeder, 1901 is redescribed and illustrated. Photomicrographs of its tegumental surfaces as revealed by scanning electron microscopy are given. Additional information on Bilatorchis papillogenitalis Eduardo, 1980 is included. Part of a thesis approved by the University of London for the award of the Ph.D. degree. Part of a thesis approved by the University of London for the award of the Ph.D. degree.     

Ultrastructural observations on the sensory papillae of juvenile and adult Gorgoderina vitelliloba (Trematoda: Gorgoderidae)

Hoole D. and Mitchell J.B. 1981. Ultrastructural observations on the sensory papillae of juvenile and adult Gorgoderina vitelliloba (Trematoda : Gorgoderidae). International Journal for Parasitology11: 411–417. Ultrastructural observations have been made on the juvenile and adult stages of Gorgoderina vitelliloba from Rana temporaria. Four types of sensory papillae occur; button, rosette, ciliated and domed. Button papillae, which contain a ciliary-rootlet but lack a cilium, occur on the oral sucker, dorsal preacetabular surface and the lateral margins of the fluke. Scanning electron microscopical observations reveal that the tegumental protuberances of the papilla are transformed from a spiked or conical appearance in juvenile flukes to a rounded form in adult flukes. Rosette papillae, which also contain a rootlet, occur on the lip of the ventral sucker of both juvenile and adult flukes. Ciliated papillae only occur on the oral sucker of juvenile flukes. Domed papillae, which contain a large area of electron-dense material, occur on the internal surface of the ventral sucker of both juvenile and adult flukes. The functions of papillae and their possible role in the migration of the parasite are discussed.     

Tegumental ultrastructure of the juvenile and adult Himasthla alincia (Digenea: Echinostomatidae)

The tegumental ultrastructure of juvenile and adult Himasthla alincia (Digenea: Echinostomatidae) was observed by scanning electron microscopy. One-, 5- (juveniles) and 20-day-old worms (adults) were harvested from chicks experimentally fed metacercariae from a bivalve, Mactra veneriformis. The juvenile worms were elongated and curved ventrally. The head crown bore 31 collar spines, arranged in a single row. The lip of the oral sucker had 12 paired, and 3 single type I sensory papillae, and the ventral sucker had about 25 type II sensory papillae. The anterolateral surface between the two suckers was densely packed with tegumental spines with 4-7 pointed tips. The adult worms were more elongated and filamentous, and had severe transverse folds over the whole body surface. On the head crown and two suckers, type I and II sensory papillae were more densely distributed than in the juvenile worms. Retractile brush-like spines, with 8-10 digits, were seen on the anterolateral surface, whereas claw-shaped spines, with 2-5 digits, were sparsely distributed posteriorly to the ventral sucker. The cirrus characteristically protruded out, and was armed with small spines distally. The surface ultrastructure of H. alincia was shown to be unique among echinostomes, especially in the digitation of its tegumental spines, the distribution of sensory papillae and by severe folds of the tegument.