Fig 5 - uploaded by Inés S Incorvaia
Content may be subject to copyright.
Clestobothrium cristinae sp. n. from Merluccius hubbsi . A – scolex showing contracted U-shaped muscular sphincter; dorso- ventral view, holotype (MACN-Pa 511/1); B – scolex relaxed showing musculature of bothria; dorsoventral view, paratype (MACN- Pa 511/2); C – mature proglottides; vitelline follicles only illustrated in posterior proglottis; osmoregulatory canals not illustrated; dorsal view, holotype (MACN-Pa 511/1); D – eggs with operculum; E – transverse cross-section of mature proglottis at level of geni- tal pore; paratype (MACN-Pa 511/2); F – transverse cross-section of mature proglottis at level of ovary; paratype (MACN-Pa 511/2). Abbreviations : cs – cirrus-sac; gp – genital pore; lm – bundles of longitudinal musculature; msp – muscular sphincter; nc – nerve cord; nm – narrow muscle; oc – osmoregulatory canals; op – operculum; ov – ovary; sa – spurious articulation; t – testes; up – uterine pore; ut – uterus; vf – vitelline follicles; vg – vagina. Scale bars: A–D = 500 μm; E, F = 250 μm.
Source publication
Abstract: Two new species of bothriocephalidean cestodes, Clestobothrium splendidum sp. n. from Merluccius australis (Hutton) and Clestobothrium cristinae sp. n. from Merluccius hubbsi Marini from the Patagonian shelf of Argentina, are described. Clestobothrium splendidum can be typified by the following characteristics: a medium-sized strobila com...
Contexts in source publication
Context 1
... of proglottis vs. posterior, strongly folliculate and markedly extended towards the anterior part of the proglottis), and the pres- ence of some testes posterior to the ovary (vs. absence of testes posterior to the ovary); and from C. gibsoni in the distribution of vitelline follicles (one layer vs. 2-3 layers as shown by Dronen and Blend 2005, fig. 5), distribution of testes (two lateral fields, each of which is divided into two fields vs. two undivided lateral fields) and presence of testes posterior to the ovary (vs. absence of testes pos- terior to the ...
Context 2
... globular to oval, projecting posteriorly over first proglottis, 435-1,050 (675) × 450-800 (560) (n = 12). scolex divided by longitudinal grooves into 2 dorsoven- tral hemispheres. apical disk weekly developed forming (Figs. 5a, 6a). Bothria aperture elongated when fully relaxed (Fig. 5B). surface around aperture of bothria covered with capilliform filitriches 1.60-1.90 × 1.15 (n = 2), interspersed with gladiate spinitriches 2.50- 2.70 × 0.25-0.30 (n = 2). Posterior projection of scolex covered with scarce capilliform filitriches (not measured due to curled ...
Context 3
... globular to oval, projecting posteriorly over first proglottis, 435-1,050 (675) × 450-800 (560) (n = 12). scolex divided by longitudinal grooves into 2 dorsoven- tral hemispheres. apical disk weekly developed forming (Figs. 5a, 6a). Bothria aperture elongated when fully relaxed (Fig. 5B). surface around aperture of bothria covered with capilliform filitriches 1.60-1.90 × 1.15 (n = 2), interspersed with gladiate spinitriches 2.50- 2.70 × 0.25-0.30 (n = 2). Posterior projection of scolex covered with scarce capilliform filitriches (not measured due to curled position) interspersed with long gladiate spinitriches ...
Context 4
... osmoregu- latory canals medullary, 3 pairs on each side of proglottis, 1 larger pair separating fields of testes from other genital organs 15-30 in diameter, 1 pair between wide internal field and narrow external field of testes 10-15 in diameter and 1 smaller pair external to fields of testes, 5-15 in di- ameter in transverse sections (Fig. 5E, F). (Figs. 1B, 5c, 6D, F, g). testes medullary, spherical to slightly oval 40-100 (62 ± 13) (n = 33) in diameter; 39-64 (49) (n = 10) per mature proglottis, distributed in 1 layer occupying 2 lat- eral fields, each one divided into one wide internal field and one narrow external field, best distinguishable in immature and first mature ...
Context 5
... diameter; 39-64 (49) (n = 10) per mature proglottis, distributed in 1 layer occupying 2 lat- eral fields, each one divided into one wide internal field and one narrow external field, best distinguishable in immature and first mature proglottides. Testes continu- ous from proglottis to proglottis, usually completely sur- rounding ovary posteriorly (Fig. 5c, E, F). genital pore dorsal, submedian, rounded, at same level of spurious ar- ticulations when present (Fig. 6F), situated 32-62% (48) (BMNH 1976.4.12.152-154); B -mature proglottides, vitelline follicles only illus- trated in anterior proglottis; dorsal view, voucher (BMNH 1989.7.6.17); C -scolex showing musculature of bothria; lateral ...
Context 6
... = 42) from anterior margin of mature proglottis; genital atrium not observed. cirrus-sac oval to globular, small, thick-walled, irregularly alternating dextrally or sinis- trally to median line in successive proglottides, 70-120 (88) × 60-80 (71) (n = 14) in diameter, occupying 8-16% (10%) (n = 12) of proglottis width in mature proglottides (Fig. 5c). cirrus unarmed occupying 40-50% of cirrus- sac length. seminal vesicle not observed. Vas deferens strongly coiled, situated anterolaterally (Fig. 5c, E). ovary medullary, post-equatorial, bilobed, slightly folliculate, transversely elongated or slightly U-shaped 200-400 (245) (n = 44) wide; occupying 22-49% (29) (n = 44) of proglottis ...
Context 7
... dextrally or sinis- trally to median line in successive proglottides, 70-120 (88) × 60-80 (71) (n = 14) in diameter, occupying 8-16% (10%) (n = 12) of proglottis width in mature proglottides (Fig. 5c). cirrus unarmed occupying 40-50% of cirrus- sac length. seminal vesicle not observed. Vas deferens strongly coiled, situated anterolaterally (Fig. 5c, E). ovary medullary, post-equatorial, bilobed, slightly folliculate, transversely elongated or slightly U-shaped 200-400 (245) (n = 44) wide; occupying 22-49% (29) (n = 44) of proglottis width in mature proglottides (Fig. 5c, F). Vaginal canal situated between ovary lobes, vagi- nal sphincter and seminal receptacle not observed (Fig. 5c, ...
Context 8
... 40-50% of cirrus- sac length. seminal vesicle not observed. Vas deferens strongly coiled, situated anterolaterally (Fig. 5c, E). ovary medullary, post-equatorial, bilobed, slightly folliculate, transversely elongated or slightly U-shaped 200-400 (245) (n = 44) wide; occupying 22-49% (29) (n = 44) of proglottis width in mature proglottides (Fig. 5c, F). Vaginal canal situated between ovary lobes, vagi- nal sphincter and seminal receptacle not observed (Fig. 5c, F). Vitelline follicles densely distributed in one cir- cumcortical layer, forming continuous field around mar- gins of proglottis in transverse section and from proglot- tis to proglottis; interrupted dorsally at level of ...
Context 9
... (Fig. 5c, E). ovary medullary, post-equatorial, bilobed, slightly folliculate, transversely elongated or slightly U-shaped 200-400 (245) (n = 44) wide; occupying 22-49% (29) (n = 44) of proglottis width in mature proglottides (Fig. 5c, F). Vaginal canal situated between ovary lobes, vagi- nal sphincter and seminal receptacle not observed (Fig. 5c, F). Vitelline follicles densely distributed in one cir- cumcortical layer, forming continuous field around mar- gins of proglottis in transverse section and from proglot- tis to proglottis; interrupted dorsally at level of genital pore and ventrally at level of uterus when gravid. Folli- cles spherical to oval 30-60 (45) (n = 24) in ...
Context 10
... enlarged in gravid proglottides, forming a uterine-sac occupying 12-45% (26 ± 10%) (n = 38) of gravid proglottis width, usually extends towards preced- ing proglottis. Uterine pore ventral, median to submedian, at anterior margin of proglottis, generally overlapped by velum-like posterior margin of preceding proglottis in mature proglottides (Figs. 5C, 6G). Eggs oval 60-65 × 40-45 (n = 4), unembryonated, with inconspicuous oper- culum (Fig. 5D). Remarks. the new species is assigned to Clestoboth- rium because it has the scolex features above mentioned and the diagnostic characteristics of this genus given by Bray et al. (1994) and Kuchta et al. ...
Context 11
... of gravid proglottis width, usually extends towards preced- ing proglottis. Uterine pore ventral, median to submedian, at anterior margin of proglottis, generally overlapped by velum-like posterior margin of preceding proglottis in mature proglottides (Figs. 5C, 6G). Eggs oval 60-65 × 40-45 (n = 4), unembryonated, with inconspicuous oper- culum (Fig. 5D). Remarks. the new species is assigned to Clestoboth- rium because it has the scolex features above mentioned and the diagnostic characteristics of this genus given by Bray et al. (1994) and Kuchta et al. ...
Context 12
... and 70-90, respectively). in addition, the new species differs from C. gibsoni in the distribu- tion of testes (two lateral fields, each one divided into one wide internal field and one narrow external field vs. two undivided lateral fields) and the distribution of vitelline follicles (one layer vs. 2-3 layers as shown by Dronen and Blend 2005 fig. 5). Clestobothrium cristinae is also distinguished from C. neglectum in that its proglottides do not show a scalloped pattern of longitudinal ridges across the ventral and dorsal ...
Similar publications
Post-recruit Illex argentinus were collected from the fishery on the Patagonian Shelf between 1986 and 1988. Age was determined by analysis of daily growth increments in ground sections of the statolith, female fecundity was determined, specimens were dissected, weighed and assigned a maturity stage. The relation between mantle length and age is be...
Citations
... This type of spinitriches includes a diversity of forms that differ in the shape and position of the three prongs that define this spinithrix (Chervy, 2009). The trifid spinitriches studied internally by Palm (2000) (Chervy, 2009;Gil de Pertierra, Incorvaia, & Arredondo, 2011;Ivanov, 2008;Koch, Jensen, & Caira, 2012;Pickering & Caira, 2012;Yoneva et al., 2017). Both, the external shape and the internal structure are quite similar in members of different orders (Fyler, 2007;Levron et al., 2008;McCullough & Fairweather, 1984;Zd'árská et al., 2004). ...
The ultrastructure of the scolex of Orygmatobothrium schmittii (Cestoda: Phyllobothriidae) was studied using histochemistry, scanning, and transmission electron microscopy. The central bothridial structure resulted in a glandulomuscular organ formed by a mass of syncytial glands and radial muscles, with glycoprotein secretions potentially adhesive. Among the sensory receptors found on the scolex, a particular type was found surrounding the glandulomuscular organ, which might be related in the regulation of the secretions. The internal structure of the microtriches revealed a diversity of configurations according to their morphotype and distribution on the scolex. Microtriches with larger caps are thought to be useful for attachment purposes. In addition, the thick bounding membranes of the attachment organs and the circular musculature in the bothridia, seem to aid to the attachment of the scolex to the mucosa of the host.
... Bothiocephalidean cestodes are widely distributed parasites of marine and freshwater fishes with a few species parasitising amphibians (Schmidt, 1986; Bray et al., 1994;). There is little information on the diversity of these tapeworms in fishes of Argentina (Szidat, 1955Szidat, , 1961 Suriano & Labriola, 1998; Gil de Pertierra & Semenas, 2005, 2006 Gil de Pertierra et al., 2011). The parasitic fauna of fish species belonging to the family Bovichtidae (i.e. the genera Bovichtus Valenciennes , Cottoperca Steindachner and Halaphritis Last, Balushkin & Hutchins) is poorly known. ...
... The new species belongs to Bothriocephalus within the Bothriocephalidae Blanchard, 1849 (see Kuchta et al., 2008) based on the presence of an unarmed scolex with two elongate bothria that open posterior without a posterior U-shaped sphincter, and an anterior tendon (see Rees, 1958; Kuchta et al., 2008; Gil de Pertierra et al., 2011); a well-developed apical disc on the scolex; medullary testes arranged in two continuous lateral bands along the strobila; an elongate cirrus-sac and unarmed cirrus; a medial genital pore; a posteriorly situated ovary; a vagina that is situated posterior to the cirrus sac; numerous vitelline follicles that are arranged in a continuous field around proglottides; a submedian uterine pore; and unembryonated, operculate eggs. Bothriocephalus timii n. sp. is characterised by the following combination of features: a strobila composed of segments and proglottides usually longer than wide, possessing posterolateral wing-like expansions with a medial notch on both the dorsal and ventral surfaces; a scolex with an apical disk, elongate bothria opening posteriorly with lateral and longitudinally extended convex lappets which may overlap or not; testes in single layer forming two lateral longitudinal continuous bands along the strobila, 42–185 (78) in number per mature proglottis; an elongate cirrus-sac which is placed obliquely, with its proximal part curved anterolaterally and a length/width ratio of 1:1.3–3.8 (1:2.2); and an ovary which is usually butterfly-shaped and occupies about 23% of proglottis width. ...
Bothriocephalus timii n. sp. is the first tapeworm species reported from a bovichtid fish. The new species was commonly found (prevalence 85%) in the intestine of Cottoperca gobio (Günther) collected on the Patagonian shelf off Argentina. It is characterised by a strobila with segments and proglottides usually longer than wide, having posterolateral wing-like expansions with a medial notch on both the dorsal and ventral surfaces; a scolex with an apical disk; elongate bothria opening posteriorly, with laterally and longitudinally extended convex lappets; testes 42-185 in number, in one layer, arranged in two lateral continuous bands along the strobila; an elongate cirrus-sac, situated obliquely, with the proximal part curved anteriolaterally; and an ovary which is usually butterfly-shaped. The new species is morphologically similar to B. bengalensis Devi, 1975 from Carangoides plagiotaeniata Bleeker, B. branchiostegi Yamaguti, 1952 from Branchiostegus japonicus Houttuyn, B. carangis Yamaguti, 1968 from C. ferdau Forsskål and B. gadellus Blend & Dronen, 2003 from Gadella imberbis (Vaillant) based on the presence of posterolateral wing-like expansions with a medial notch on dorsal and ventral surfaces of segments and proglottides along the strobila. Bothriocephalus timii n. sp. differs from B. bengalensis, B. branchiostegi and B. carangis in the absence of a vaginal sphincter and from B. gadellus in the number of testes and the size of scolex. Unpublished molecular data suggest that B. timii is most closely related to B. australis Kuchta, Scholz & Justine, 2009 from Platycephalus spp. and B. scorpii (Müller, 1776) from Myoxocephalus scorpius (Linnaeus). The genus Indobothrium Sedova & Gulyaev, 2009 is herein considered a junior synonym of Bothriocephalus Rudolphi, 1808.
An exhaustive literature search supplemented by a critical examination of records made it possible to present
an annotated checklist of tapeworms (Cestoda) that, as adults or larvae (metacestodes), parasitize freshwater,
brackish water and marine fishes, i.e. cartilaginous and bony fishes, in South America. The current
knowledge of their species diversity, host associations and geographical distribution is reviewed. Taxonomic
problems are discussed based on a critical evaluation of the literature and information on DNA sequences of
individual taxa is provided to facilitate future taxonomic and phylogenetic studies. As expected, the current
knowledge is quite uneven regarding the number of taxa and host-associations reported from the principal
river basins and marine ecoregions. These differences may not only reflect the actual cestode richness but
may also be due to the research effort that has been devoted to unravelling the diversity of these endoparasitic
helminths in individual countries. A total of 297 valid species, 61 taxa identified to the generic level,
in addition to unidentified cestodes, were recorded from 401 species of fish hosts. Among the recognized
cestode orders, 13 have been recorded in South America, with the Onchoproteocephalidea displaying the
highest species richness, representing c. 50% of all species diversity. The majority of records include teleost
fish hosts (79%) that harbour larval and adult stages of cestodes, whereas stingrays (Myliobatiformes) exhibit
the highest proportion of records (39%) among the elasmobranch hosts. Fish cestodes are ubiquitous
in South America, being mostly recorded from the Warm Temperate Southeastern Pacific (WTSP; 31%)
for marine hosts and the Amazon River basin (45%) for freshwater ones. The following problems were
detected during the compilation of literary data: (i) unreliability of many records; (ii) poor taxonomic
resolution, i.e. identification made only to the genus or even family level; (iii) doubtful host identification; and (iv) the absence of voucher specimens that would enable us to verify identification. It is thus strongly
recommended to always deposit representative specimens in any type of studies, including faunal surveys
and ecological studies. An analysis of the proportion of three basic types of studies, i.e. surveys, taxonomic
and ecological papers, has shown a considerable increase of ecological studies over the last decade.
The early intrauterine embryonic development of the bothriocephalidean cestode Clestobothrium crassiceps (Rudolphi, 1819), a parasite of the teleost Merluccius merluccius (L., 1758), was studied by means of light (LM) and transmission electron microscopy (TEM). Contrary to the generic diagnosis given in the CABI Keys to the cestode parasites of vertebrates, the eggs of C. crassiceps, the type of species of Clestobothrium Lühe, 1899, are operculate and embryonated. Our LM and TEM results provide direct evidence that an operculum is present and that the eggs exhibit various stages of intrauterine embryonic development, and in fact represent a good example of early ovoviviparity. The intrauterine eggs of this species are polylecithal and contain numerous vitellocytes, generally∼30, which are pushed to the periphery and remain close to the eggshell, whereas the dividing zygote and later the early embryo remain in the egg centre. During early intrauterine embryonic development, several cleavage divisions take place, which result in the formation of three types of blastomeres, i.e. macro-, meso- and micromeres. These can be readily differentiated at the TEM level, not only by their size, but also by the ultrastructural characteristics of their nuclei and cytoplasmic organelles. The total number of blastomeres in these early embryos, enclosed within the electron-dense eggshells, can be up to∼20 cells of various sizes and characteristics. Mitotic divisions of early blastomeres were frequently observed at both LM and TEM levels. Simultaneously with the mitotic cleavage divisions leading to blastomere multiplication and their rapid differentiation, there is also a deterioration of some blastomeres, mainly micromeres. A similar degeneration of vitellocytes begins even earlier. Both processes show a progressive degeneration of both vitellocytes and micromeres, and are good examples of apoptosis, a process that provides nutritive substances, including lipids, for the developing embryo.
The scolex of the bothriocephalidean cestode Clestobothrium crassiceps was studied by means of scanning electron microscopy (SEM). The comparative results of various fixation procedures and techniques are presented. The scolex of C. crassiceps is oval to globular and exhibits two deep bothria which appear in the form of two lobes separated by a longitudinal groove. At the apex of the scolex, resembling a beret, an apical disc is present (oval, flattened and with a sinuous edge). Our results are compared with those previously reported in other species of Clestobothrium. This study represents the first report which highlights the presence of an apical disc in the scolex of C. crassiceps. It describes the effects of different procedures applied to our material during preparation and a comparative analysis results obtained using these various methods.
