In the present study two new species of Tetragonocephalum Shipley et Hornell, 1905, T. mackenziei sp. n. and T. kazemii sp. n., are described from the spiral intestine of the cowtail stingray, Pastinachus sephen (Forsskål), from the northern coast of the Gulf of Oman. Tetragonocephalum mackenziei is distinguished from the 16 other valid species of Tetragonocephalum by a unique combination of characteristics, i.e. sperm-filled seminal receptacle in immature proglottids, body length (7.7-17.5 mm), body width (213-288 µm), number of proglottids (34-49), number of testes (10-14), size of scolex (228-315 µm × 213-288 µm) and size of acetabula (56-73 µm × 61-75 µm). Tetragonocephalum kazemii is morphologically distinguishable from its valid congeners and T. mackenziei based on a combination of characteristics, including body length (28.8-36.6 mm), number of proglottids (50-65), number of testes (30-42), size of scolex (388-564 µm × 326-448 µm), size of acetabula (62-86 µm × 57-90 µm) and testes (25-39 × 21-32). This brings the total number of validly described species of Tetragonocephalum to 18 and expands our knowledge of this diverse genus to now include the Gulf of Oman, as well as Arafura Sea, northern Indian Ocean and western Pacific Ocean., Atabak Roohi Aminjan, Masoumeh Malek., and Obsahuje bibliografii
During investigations of gill ectoparasites (Platyhelminthes) parasitising freshwater fish from Central America (Guatemala, Honduras, El Salvador and Panama) and southeastern Mexico (Guerrero, Oaxaca and Chiapas), the following dactylogyrid monogenoidean were found: Urocleidoides simonae sp. n. from Profundulus punctatus (Günther) (type host), Profundulus balsanus Ahl, Profundulus guatemalensis (Günther), Profundulus kreiseri Matamoros, Shaefer, Hernández et Chakrabarty, Profundulus labialis (Günther), Profundulus oaxacae (Meek), Profundulus sp. 1 and Profundulus sp. 2 (all Profundulidae); Urocleidoides vaginoclaustroides sp. n. from Pseudoxiphophorus bimaculata (Heckel) (type host) and Poeciliopsis retropinna (Regan) (both Poeciliidae); and Urocleidoides vaginoclaustrum Jogunoori, Kritsky et Venkatanarasaiah, 2004 from P. labialis, Profundulus portillorum Matamoros et Shaefer and Xiphophorus hellerii Heckel (Poeciliidae). Urocleidoides simonae sp. n. differs from all other congeneric species in having anchors with well-differentiated roots, curved elongate shaft and short point. Urocleidoides vaginoclaustroides sp. n. most closely resembles U. vaginoclaustrum, but differs from this species mainly in the shape of its anchors (i.e. evenly curved shaft and short point vs curved shaft and elongate point extending just past the tip of the superficial anchor root). The complexity of potential hosts for species of Urocleidoides and their effect on its distribution on profundulid and poeciliid fishes are briefly discussed., Edgar F. Mendoza-Franco, Juan Manuel Caspeta-Mandujano, Guillermo Salgado-Maldonado, Wilfredo Antonio Matamoros., and Obsahuje bibliografii
Two closely related parasitoid wasp species with different host specificities were used for experimental studies on the biology of host finding, a crucial element of parasitoid life history: The habitat and host specialist Nasonia vitripennis and the habitat and host generalist Dibrachys microgastri (Chalcidoidea: Pteromalidae). The host finding parameters tested included reaction to olfactory cues, aspects of locomotor activity, ability to locate hidden hosts and day-night-activity. The results revealed distinct interspecific differences that match the respective host and habitat ranges of the two species. In N. vitripennis host finding is dominated by olfactory reaction to hosts and host habitat, i.e., fly puparia and birds' nests. In D. microgastri olfactory cues have only a minor role. Its host finding is characterized by rapid searching at random. Both species are able to locate hidden hosts. Although still incomplete, these insights into host finding by two parasitoid species with different life history strategies indicate they can be characterized by specific combinations of behavioural host finding features. and Ralph S. Peters.
A new microsporidian species of the genus Glugea Thélohan, 1891 parasitising the marine teleost fish Cephalopholis hemistiktos Rüppell, collected from the Red Sea in Saudi Arabia, is described on the basis of microscopic and molecular procedures. Spherical and whitish xenoma were observed adhering to the intestinal wall. The numerous spores contained within these xenoma, were ovoid to pyriform and measured 4.3-6.0 µm (5.1 µm) in length and 1.8-2.9 µm (2.2 µm) in width. The spore's wall was composed of two thick layers, which were thinner in the area contacting the anchoring disk. The latter appeared at the spore's anterior pole, in an eccentric position to the longitudinal axis. A lamellar polaroplast surrounded the uncoiled portion of the polar filament projected to the basal region of the spore, giving rise to 26-29 turns with winding from the base to the anterior zone of the spore. The posterior vacuole, located at the spore's posterior pole, and surrounded by the polar filament coils, was irregular and composed of light material. Molecular analysis of the rRNA genes, including the ITS region, was performed using maximum parsimony, neighbour-joining and maximum likelihood methods. The ultrastructural features observed, combined with the phylogenetic data analysed, suggest this parasite to be a new species of the genus Glugea. This is the first species of this genus to be reported from Saudi Arabia and is herein named Glugea nagelia sp. n., Abdel-Azeem S. Abdel-Baki, Saleh Al-Quraishy, Sónia Rocha, Mohamed A. Dkhil, Graça Casal, Carlos Azevedo., and Obsahuje bibliografii
Using scanning and transmission electron microscopy, ultrastructure of the anterior organ and posterior funnel-shaped canal of Gyrocotyle urna Wagener, 1852 (Cestoda: Gyrocotylidea) from ratfish, Chimaera monstrosa (Holocephali), was studied for the first time. The proper anterior organ is localised at a short distance (about 170 µm) from an apical pore surrounded by a receptor field, whereas its distal end is marked by a muscular sphincter. The tegumental surface of this organ is covered with short filitriches of irregular length; large area of muscle layers traverse beneath the tegumental layer. The funnel-shaped canal of G. urna (2.5-3.0 mm long) is a specialised, muscular part of the posterior attachment organ; it opens on the rounded elevation on the dorsal body surface. The tegumental layer bears conical sclerite-like structures (up to 1.5 µm long). It produces electron-dense bodies that are transported into a canal lumen and surrounded thick muscle area mixed with numerous nerve fibres. The present ultrastructural study of G. urna indicates that gyrocotylideans share some ultrastructural characters of the anterior organ with spathebothriidean cestodes with a single anterior attachment sucker-like organ. In contrast, the unique posterior rosette attachment organ with funnel-shaped canal of the Gyrocotylidea resembles the haptor of polyopisthocotylean monogeneans in its position at the posterior end of the body and presumed origin. The above-mentioned features add more clarity to support the basal position of the Gyrocotylidea Poche, 1926 among cestodes. In addition, they also indicate a possible relationship of gyrocotylidean ancestors with monogeneans., Larisa G. Poddubnaya, Roman Kuchta, Glenn A. Bristow, Tomáš Scholz., and Obsahuje bibliografii
In the present paper, we describe the ultrastructure of the spermatozoon of the notocotylid Notocotylus noyeri (Joyeux, 1922) by means of transmission electron microscopy. The mature spermatozoon of N. noyeri exhibits the general pattern described in the majority of digeneans: two axonemes of the 9 + "1" pattern of the Trepaxonemata, nucleus, mitochondria, parallel cortical microtubules, spine-like bodies and ornamentation of the plasma membrane. The glycogenic nature of the electron-dense granules was evidenced applying the test of Thiéry. The ultrastructural features of the spermatozoon of N. noyeri present some differences in relation to those of the Pronocephalidea described until now, but confirm a general pattern for the Notocotylidae, namely a spermatozoon with two mitochondria and an anterior region with ornamentation of the plasma membrane associated with spine-like bodies. The posterior extremity of the spermatozoon exhibits only some microtubules after the disorganisation of the second axoneme. The present study confirms that some ultrastructural characters of the sperm cell such as the presence or absence of lateral expansions, the number of mitochondria and the morphology of both anterior and posterior spermatozoon extremities are useful for phylogenetic purposes within the Pronocephaloidea. Thus, unlike notocotylids, pronocephalids exhibit external ornamentation and a lateral expansion in the anterior spermatozoon region. Moreover, notocotylid spermatozoa present two mitochondria, whereas pronocephalid spermatozoa exhibit a single mitochondrion. Finally, pronocephalids are characterised by a type 2 posterior spermatozoon extremity, whereas notocotylids exhibit a type 3 posterior spermatozoon extremity., Papa Ibnou Ndiaye, Jordi Torres, Catarina Eira, Vladimir V. Shimalov, Jordi Miquel., and Obsahuje bibliografii
Using sequence alignment, a conserved domain in the 3' untranslated region (UTR) of the cytoplasmic heat shock protein 90 (HSP90) of Lepidoptera was found. This region is highly variable in other insect groups. Furthermore, universal primers were designed to amplify the complete coding sequence (CDS) of HSP90 from total genomic DNA in Lepidoptera, avoiding the commonly used reverse transcription-polymerase chain reaction (RT-PCR) and 3', 5'-rapid amplification of cDNA ends (RACE) methods based on cDNA. These primers amplified a fragment of about 2.25 kb in the 11 species tested, which represent seven different families of Lepidoptera, including moths and butterflies. The results suggest that the conserved domain of 3'UTR is universal in Lepidoptera and these primers successfully amplify the complete CDS of cytoplasmic HSP90 from genomic DNA. and Peng Jun XU, Tong LI, Jin Hua XIAO, Robert W. MURPHY, Huang DA WEI.
Larvae of the stag beetle, Dorcus rectus, feed on decaying wood, which they digest with the aid of symbiotic yeasts; however, they can be successfully reared on artificial diets containing only fungal tissue. In this study we tested whether D. rectus larvae can utilize fungal cell walls, which are an insoluble component of mycelium. Lyophilized Bjerkandera adusta mycelium cultured in potato-dextrose liquid medium consisted of a 47.6% hot-water insoluble fraction by mass, which contains 53.7% of the total nitrogen in the mycelium. D. rectus larvae that hatched from surface-sterilized eggs were reared for 14 days on agar-based diets containing either the soluble fraction, insoluble fraction or both, extracted from 100 mg of mycelium. The larvae increased in mass most on the mixed diet, and there was no difference in their growth on the mixed and positive control diets. Both the soluble and insoluble fractions improved larval growth compared to the negative control diet; however, the growth rates were much lower than those expected from the nitrogen dose-growth response curve obtained in a previous study. Addition of b-chitin to the soluble fraction did not positively affect larval growth. Therefore, we conclude that (1) D. rectus larvae need both the soluble and insoluble fractions of mycelium and (2) the larvae digest the insoluble fraction using their own enzymes., Masahiko Tanahashi, Kôhei Kubota., and Seznam literatury