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1.
Lagenophrys eupagurus , a poorly known loricate peritrich ectocommensal on the hermit crab Pagurus longicarpus , has been rediscovered and is redescribed. Lagenophrys lunatus and L. articularis were found to be conspecific with L. eupagurus based on close similarities, especially with regard to structure of the lorica aperture and proportions of the lorica. Lagenophrys callinectes , although resembling L. eupagurus , was determined to be a separate species because of distinct, consistent differences in structure of the lorica aperture and proportions of the lorica. Lagenophrys eupagurus and L. callinectes share some features of the lorica aperture with 3 other species of Lagenophrys , prompting the speculation that the 5 species may constitute a cluster of related species within the genus. Lagenophrys eupagurus utilizes a relatively wide variety of hosts compared to other species of Lagenophrys and appears to subsist mainly on phytoplankton. In some cases, the feeding behavior of the host may assist L. eupagurus in obtaining food. Lagenophrys callinectes appears to be restricted to brachyuran crabs of the genus Callinectes. It appears to be a bacterivore and is probably assisted in obtaining food by the preference of its hosts for estuarine areas that are rich in organic material.  相似文献   

2.
Abstract

Cyllobelus rufopictus? a salticid species from equatorial Africa, has a large and complex repertoire of displays. These spiders live on and near the ground in habitats of short grass, and build opaque silk nests on dead leaves. Each male uses one of three different mating tactics depending on the female’s maturity and location (communicatory versatility). Type 1 courtship, involving special movements and postures of the legs, palps, and body, occurs if the female is an adult away from the nest; apparently this type of courtship is vision-dependent. If the male encounters an adult female inside her nest, he uses Type 2 courtship, which consists of movements by the male that cause the silk to vibrate. If the female is a subadult inside her nest, the male initially uses Type 2 courtship, then builds a second chamber on the female’s nest, and cohabits until she moults and matures. Other displays occur during male-male and female-female interactions. Biting and pinching are distinctive Type 2 courtship displays that have not been described previously for salticids, and juddering is the most distinctive Type 1 display.  相似文献   

3.
Ten species of lagenophryid peritrichs in three genera are redescribed or described for the first time. Based on this information, the family Lagenophryidae was found to consist of five genera: Lagenophrys, Paralagenophrys, Clistolagenophrys n. g., Setonophrys, and Operculigera. Lagenophryid genera differ in gross structure of the lorica aperture and the peristomial sphincter associated with it. Shape of the lorica and mode of attachment to the host are not generic characteristics in the Lagenophryidae. Differences in shape evolved within each of the three largest lagenophryid genera merely as adaptations for attachment to different parts of a host. Usconophrys, formerly in the Lagenophryidae, and Cyclodonta are assigned to the family Usconophryidae n. fam., which is characterized by possession of a lorica, lack of a closure apparatus operated by the peristomial sphincter, and possession of an operculariform peristome. Lagenophrys, Setonophrys, and Paralagenophrys appear to have evolved separately and convergently from ancestors within Operculigera. Lagenophryid lorica apertures consisting of opposing lips probably evolved as tight seals to prevent water loss when the host is temporarily out of water. The greater diversity and wider distribution of Lagenophrys compared with other lagenophryid genera may result from an advantage in recolonizing hosts conferred by second-type division.  相似文献   

4.
Ten species of lagenophryid peritrichs in three genera are redescribed or described for the first time. Based on this information, the family Lagenophryidae was found to consist of five genera: Lagenophrys, Paralagenophrys, Clistolagenophrys n. g., Setonophrys, and Operculigera. Lagenophryid genera differ in gross structure of the lorica aperture and the peristomial sphincter associated with it. Shape of the lorica and mode of attachment to the host are not generic characteristics in the Lagenophryidae. Differences in shape evolved within each of the three largest lagenophryid genera merely as adaptations for attachment to different parts of a host. Usconophrys, formerly in the Lagenophryidae, and Cyclodonta are assigned to the family Usconophryidae n. fam., which is characterized by possession of a lorica, lack of a closure apparatus operated by the peristomial sphincter, and possession of an operculariform peristome. Lagenophrys, Setonophrys, and Paralagenophrys appear to have evolved separately and convergently from ancestors within Operculigera. Lagenophryid lorica apertures consisting of opposing lips probably evolved as tight seals to prevent water loss when the host is temporarily out of water. The greater diversity and wider distribution of Lagenophrys compared with other lagenophryid genera may result from an advantage in recolonizing hosts conferred by second-type division.  相似文献   

5.
Five species of the loricate genus Lagenophrys were found on freshwater hosts and are described for the first time. Lagenophrys dennisi n. sp., L. incompta n. sp., and L. oregonensis n. sp. are ectosymbionts of astacid crayfish. Lagenophrys foxi n. sp and L. missouriensis n. sp. are ectosymbionts of gammarid amphipods. All five species appear to occur only m North America. Protargol preparations of the five species reveal that the peristomial myoneme is much broader and more extensive in telotrochs and metamorphosing individuals than in adults. Darkly staining bands appearing to be somatic myonemes were also seen underneath the surface of the body and in the center of the body of telotrochs and metamorphosing individuals. The telotroch of Lagenophrys is so different from the adult that it constitutes a true larval form rather than a simple dispersal stage. Structural parallels between the telotroch of Lagenophrys and mobiline peritrichs suggest the hypothesis that mobilines evolved from the telotroch of a sessiline pentrich which had first evolved into a true larval form.  相似文献   

6.
The type of material of Monhystrella parvella (Filipjev, 1931) comb.n. from Abyssinia (Ethiopia) is redescribed and figured in detail. Data on the genital system and the ontogeny of this species are given. Monhystera filiformis sensu Gerlach, 1951 nec Bastian, 1865 of the Black Sea at Pomorie (Bulgaria) is synonymised with M. parvella . The Black Sea specimens have a shorter pharynx, a longer tail and differ also from the Abyssinian specimens in the shape of the tail and the spinneret outlet.  相似文献   

7.
Hemiclepsis quadrata, which is the only representative of the genus so far reported in Africa, is redescribed. Illustrations showing the diagnostic features of the taxon are provided for the first time. A thorough study of the holotype and one of the paratypes, as well as additional specimens, revealed that Moore overlooked certain important taxonomic features when he described the leech as a Batracobdella species. The transfer of this species to the genus Hemiclepsis is based on the following features exhibited by this leech: dilated head region, three pairs of eyes, central proboscis pore, ten pairs of crop caeca and small genital atria.  相似文献   

8.
ABSTRACT. Lagenophrys anticthos n. sp. resembles L. aegleae Mouchet-Bennati; however, the two species are distinguished from one another by differences in the structure of the lorica aperture. Similarities in the shape of the lorica and macronucleus indicate a close phylogenetic relationship between L. anticthos and L. aegleae. The size of L. anticthos varies greatly within a population, and it is unclear whether this can be attributed to genetic differences or to environmental factors. In L. anticthos, variation in the form of the lips of the lorica aperture is correlated with variation in size. The brown, iron-rich incrustations observed around the loricae of L. aegleae by an earlier worker were not seen, indicating that the incrustations do not play a role in the symbiosis between L. aegleae and its host as was previously thought.  相似文献   

9.
10.
11.
Synthesium pontoporiae n. comb. is redescribed, together with Synthesium tursionis and Synthesium seymouri n. comb.; the parasites were obtained from stranded and accidentally caught cetaceans. The sucker ratio (ratio between widths of the oral and ventral suckers) in S. pontoporiae was 1:1.8-3.0 (mean 1:2.2); in S. tursionis was 1:0.8-1.2; and in S. seymouri was 1:0.5-0.7. Synthesium pontoporiae differed from its congeners by additional diagnostic characters, including: oval to lobed testes; small cirrus with pyriform proximal region and flexible, tubular distal region formed by evagination of ejaculatory duct; and vitellarium in small follicles extending from the level of the seminal vesicle to the posterior extremity of the body and not forming dendritic radial bunches. Data on the morphology of adult S. pontoporiae and S. tursionis were inferred from confocal laser microscopical observations.  相似文献   

12.
13.
During faunistic study on psammophilic ciliates along the coast of Qingdao, China, a population of Trachelocerca arenicola Kahl, 1933 was found and then investigated using silver staining and gene sequencing methods. The results indicated that it represented a new genus Apotrachelocerca characterized by uninterrupted circumoral kineties composed of two rows of dikinetids and no brosse or ciliary tuft in the oral cavity. This new genus should be assigned to the family Prototrachelocercidae Foissner, 1996. Based on the small subunit rRNA gene sequence, phylogenetic trees revealed that Apotrachelocerca arenicola occupied a basal position to other trachelocercids.  相似文献   

14.
Ultrastructural study of the microsporidian Microsporidium takedai from the muscles of masu salmon Oncorhynchus masou proved that this species can be assigned to the genus Kabatana Lom, Dyková and Tonguthai, 2000. The parasites develop within disintegrated sarcoplasm without any delimiting boundary or cyst. Cylindrical multinucleate meronts proliferate by serial constrictions into uninucleate stages which repeat the process. Eventually, the uninucleate stages transform into uninucleate sporonts, which divide once to produce sporoblasts, thus functioning as sporoblast mother cells. Spores, with a subterminally located anchoring disc and 3 to 4 turns of the polar tube coil, average 3.3 by 1.9 microm in size. The exospore is divided into small fields; the endospore frequently makes small invaginations into the spore inside. Phylogenetic analysis using SSU rDNA sequence consistently placed Kabatana takedai in a group consisting of Microgemma sp., Spraguea lophii and Glugea americanus. The K. takedai could easily be separated from the other species in the same group by 2 inserts in the SSU rDNA sequence.  相似文献   

15.
The sessiline peritrich Ellobiophrya conviva n. sp. is described from marine ectoprocts of the genus Bugula, the first report of an ellobiophryid on bryozoan hosts. The new species is distinguished from others of its genus by its different body proportions, size, host, and structure of the clasping holdfast (for which the new name cinctum is chosen). Ellobiophrya conviva has been found only on B. neritina and B. turrita and shows a marked seasonal cycle of abundance. The family Ellobiophryidae Chatton & Lwoff is revised on the basis of new information provided by E. conviva, with the single species of the genus Clausophrya removed to Ellobiophrya as E. oblida Naidenova & Zaika n. comb. The genus Caliperia Laird remains unchanged. The two genera of the revised family are distinguished from one another by differences in the structure of the cinctum. Hypotheses are advanced to explain the morphogenesis of the cinctum and the evolution of ellobiophryids from other peritrichs.  相似文献   

16.
Ellobiophrya conviva clasps tentacles of the bryozoan Bugula neritina with a ring-like structure formed from aboral extensions of its body that taper into two slender arms. The tips of the arms overlap and join to form a unique organelle, the bouton. Each arm contains a massive myoneme that splays out at the bouton. The bouton consists of the cupped tips of the arms and a cavity, which is filled with dense homogeneous material. Long digitations containing longitudinal microtubules at their periphery project from the inner surface of the tip of each arm into the cavity. Deep folds of pellicle with pores opening into their depths line the wall of the cavity. Conventional kinetosomes are not visible in the bouton, but circular or elliptical arrays of microtubules are found at the bases of digitations. The nonfunctional scopula of the adult is in a depression enclosed by pellicular folds. The bouton is distant from the scopula, but its fine structure somewhat resembles it, supporting Chatton and Lwoff's hypothesis that the cinctal arms carry parts of the scopula at their tips. The fine structure of the cinctum supports their suggestion that the cinctal arms are homologous to the spasmonemes of vorticellid peritrichs.  相似文献   

17.
18.
Coprological examination of the worm lizard Diplometopon zarudnyi Nikolskii revealed the presence of oöcysts of Choleoeimeria zarudnyi (Alyousif & Al-Shawa, 2003) n. comb. in five (17%) of the 30 lizards examined. Sporulated oöcysts were found in the faeces and the gallbladder contents. These are tetrasporocystic, ellipsoidal, 25–32 × 18–25 (mean 27 × 22) μm, with a smooth bi-layered wall. The dizoic sporocysts are ovoidal, 10–13 × 6–9 (mean 11 × 7) μm, with a granulated sporocyst residuum. Sporozoites are banana-shaped with an average size of 13 × 3 μm. Endogenous stages (meronts, gamonts and gametes) are confined to the gallbladder epithelium and the infected cells were hypertrophied. Based on the morphological features of the exogenous stages and the endogenous development of the present parasite, its generic affiliation is revised and Eimeria zarudnyi Alyousif & Al-Shawa, 2003 is transferred to the genus Choleoeimeria.  相似文献   

19.
Three species of the genus Trichodina are reported from the gills of marine fishes in south-eastern Tasmania, Australia. Two of these species are new: T. australis n. sp. from five atherinid fish species, Atherinosoma microstoma, Leptatherina presbyteroides, Kestratherina brevirostris, K. esox and K. hepsetoides; and T. nesogobii n. sp. from Nesogobius sp. 1. One previously reported species, T. jadranica Raabe, 1958, was also found on Nesogobius sp. 1.  相似文献   

20.
Nematodes (1 male and numerous females) of the Philometridae were collected from the mesentery of 2 species of pimelodid catfishes, Calophysus macropterus and Perrunichthys perruno, from the Amazon River basin (fishmarket in Iquitos, Loreto District) in Peru. A detailed study of their morphology (including scanning electron microscopy) and a reexamination of the type and voucher specimens of Philometra amazonica Travassos, 1960, from Brazilian catfishes confirmed that they belong to this species and that Philometra (Alinema) alii Rasheed, 1963 is its junior synonym. Because of some marked morphological peculiarities of this species (presence of minute peribuccal sclerotized formations, a functional vagina and vulva in gravid female, and structure of the male tail), the validity of an independent genus, Alinema Rasheed, 1963, is confirmed, to which this species is transferred as Alinema amazonicum (Travassos, 1960) n. comb. This is the first record of this parasite from Peru, and P. perruno represents its new host record.  相似文献   

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