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1.
One species of Lagenophrys and two species of Operculigera are described for the first time. Lagenophrys machaerigera n. sp. was discovered on the freshwater crab Gecarcinautes goudoti and varies between two extreme forms in the structure of its lorica aperture. Operculigera carcini n. sp. was also found on G. goudoti and exhibits several characteristics that set it apart from other members of its genus. Some of these characteristics also suggest a phylogenetic link between O. carcini and the genus Lagenophrys. Operculigera madagascarensis n. sp. was discovered on the parastacid crayfish Astacoides granulimanus. The occurrence of O. madagascarensis on a Madagascan parastacid and other species of Operculigera on Chilean parastacids suggests that parastacids are the oldest hosts of the genus Operculigera. Continental drift is the most likely mechanism by which species of Operculigera and parastacids could have been dispersed to distant parts of the southern hemisphere. The absence of Operculigera on Australian parastacids may be due to its replacement by the genus Setonophrys on those hosts.  相似文献   

2.
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   

3.
Ultrastructural and protargol studies reveal that the trophont of Lagenophrys callinectes, though highly specialized, generally conforms to the basic peritrich structural pattern. Features described for L. callinectes trophonts which are unique for the genus are the fine structure and arrangement of the lorica and lips, the attachment organelle of the peristomial cytoplasm, its attachment to the loricastome walls, and the arrangement of the aboral kinetosomes of the trophont. Lack of a distinct scopularized region, and of a ventral lorica wall also characterize L. callinectes trophonts. The 4-row terminal peniculus, as revealed by protargol staining, differs from the 6-row terminal peniculus of L. nassa suggesting that the patterns of infundibular structure, as revealed by protargol, should be useful in future taxonomic studies of Lagenophrys species.  相似文献   

4.
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   

5.
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   

6.
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   

7.
8.
Lagenophrys dennisi, a peritrich ciliate, was observed attached to the exoskeleton of the crayfish Cambarellus patzcuarensis in Lake Pátzcuaro, Michoacán, Mexico. Lagenophrys dennisi presents a hemispheroidal, suboval or oval lorica in dorsal view, the distinctive lorica aperture consists of a pair of lips highly arched, unthickened, and smooth. Comparison of morphometric characters of the ciliate with previous records is made. Structures such as a "V"-shaped lorica suture, collar ridges, and myoneme are proposed for species identification. An anterior crescentic thickening on the dorsal surface of the lorica was observed under the scanning electron microscope. Lagenophryids were associated with 11 of 13 body parts with antennules and rostrum showing the highest prevalence. Lagenophrys dennisi was also found attached to submerged glass slides. This study represents the first record of L. dennisi on C. patzcuarensis and the first record of its presence in Mexico.  相似文献   

9.
Lagenophrys singularis is removed from Lagenophrys and designated the type species of Paralagenophrys n. g. Compared to members of Lagenophrys, the oral area of P. singularis is radically distorted. Paralagenophrys apparently also lacks second-type division, a special phase of sexual reproduction characteristic of Lagenophrys and associated with its adaptation to symbiotic life on crustaceans. Members of Lagenophrys are obligate ectocommensals of crustaceans. In contrast, P. singularis (Kellicott, 1887) n. comb. occurs most often on the leaves of aquatic vascular plants.  相似文献   

10.
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   

11.
A new genus, Klesovia gen. nov., with the species K. pubescens sp. nov. (Coleoptera: Curculionidae) are described from the Rovno amber. The new genus is closely related to Xylechinus (tribe Hylurgini) and distinguished by the wide flattened ovoid antennal club with rounded apex and the metepisternum covered with long thin sparse setae; it differs from other genera of Hylurgini in having a five-segmented funicle, four-segmented club, and large distance between the procoxa.  相似文献   

12.
Two new species ofConiochaeta, isolated from Japanese soils, are described and illustrated:C. cephalothecoides, which is characterized by dark brown ascomata clothed with short setae, cylindrical asci and ovoid to almond-shaped or pyriform ascospores with a longitudinal germ slit; andC. dumosa, which is characterized by dark brown ascomata clothed with short setae and dense hyphal hairs, cylindrical asci and ellipsoid-fusoid ascospores with a longitudinal germ slit. These species are distinguished from most species of the genus by the unique cephalothecoid peridium of their ascomata. The associated anamorphs of both species are assignable to the form-genusLecythophora.  相似文献   

13.
Caulophilus zherikhini, sp. nov. (Curculionidae: Cossoninae) is described from the Late Eocene Rovno amber. The new species is distinguished from all known species of the genus by its longer rostrum. It is especially similar to C. falini Davis et Engel, 2007 from Dominican amber, from which it probably differs also in the more strongly curved rostrum, less flattened body, longer and narrower profemur, and shorter elytral setae.  相似文献   

14.

Ixodes soarimalalae n. sp., Ixodes uilenbergi n. sp. and Ixodes uncus n. sp. (Acari: Ixodidae), are described based on females ex various species of tenrecs (Afrosoricida: Tenrecidae) from Madagascar. Females of all of these new species are similar to those of other species of the subgenus Afrixodes Morel, 1966 known from Madagascar, from which they can be distinguished and from one other by the size of scutum, size of scutal setae, shape of alloscutal setae, shape of genital aperture, development of genital apron, size of auriculae, size of anterior angle of basis capituli, size of palpi, dental formula on hypostome and size and development of spurs on coxa I.

  相似文献   

15.
Six species of marine tubifieids are described from the continental shelf off Peru. Two of them are members of the gutless genus Olavius Erséus, 1984 (subfamily Phallodrilinae). Olavius bullatus sp.n. possesses 2 pairs of large penial setae in voluminous copulatory sacs, tiny atria, and spermathecal pores in line with dorsal setae. Olavius crassitunicatus sp.n. is characterized by small atria with thin muscular layer, spermathecae with short ducts, opening dorso-laterally, and lack of penial setae. Four species arc members of the subfamily Limnodriloidinae. Limnodriloides busilicus sp.n. belongs to the appendiculatus-group (sensu Erséus). It is discriminated by somatic setae with subdental ligaments, and its voluminous elongate prostatic pads. Limnodriloides clavellatus sp.n. is distinguished from its congeners by a peculiar bulge in the cavity of each atrial ampulla, and spermatozeugmata imbedded in the walls of the spermathecae. Tectidrilus intermixtus sp.n. is similar to T. bori (Righi & Kanner, 1979); it is distinguished from the latter by having trisetal bundles in segment V or V-VI and by lacking copulatory glands. Marcusaedrilus peruanus sp.n. is characterized by nongranulated atrial ducts and bipartite spermathecae.  相似文献   

16.
J. H. Epler 《Hydrobiologia》1996,318(1-3):3-11
The males of three new species of Oukuriella Epler are described from Costa Rica. The genus had been previously recorded only from South America. Oukuriella annamae sp. nov. has genitalia similar to O. albistyla Epler, but differs in having transverse bands on abdominal segments In, IV, VI and VII, a lower AR, no humeral setae and fewer dorsocentral setae. Oukuriella costaricense sp. nov. differs from other described species in the genus by its brown abdomen, unnotched posterior margin of tergite IX and distinctive superior volsella, with its sharply bent, thin upper arm directed medially, and digitus small and directed caudad. Oukuriella rushi sp. nov. has apices of femora tipped with brown, a brown abdomen and distinctive superior volsella, with upper arm shorter and broader, and digitus longer then O. costaricense. The female of Oukuriella costaricense is also described. This is the first female described for the genus. Based on male and female genitalia, Oukuriella is closely related to Epedilum Townes and Zavreliella Kieffer. A key is provided to separate the males of the six described species.  相似文献   

17.
Eodiaptomus phuphanensis n. sp. is described from two localities in the Phu Phan National Park, northeast Thailand. The new species is the eighth member of the genus Eodiaptomus and the third species recorded from Thailand. It belongs to the lumholtzi‐group, and is most closely related to E. sanoamuangae Reddy and Dumont , 1998. The third endopodite‐segment of P2‐P4 in both sexes of E. phuphanensis n. sp. bears seven setae as in E. sanoamuangae, instead of six as in the remaining species of the genus. Nevertheless, the new species can be distinguished from the other congeners by the distinct shape of the endopodite of the male right P5 and the absence of hairs on lateral margins of the female caudal rami.  相似文献   

18.
A new species, Pleurotricha indica n. sp., is described, characterized by an average size of 220 × 119 μm, a firm and inflexible body, six rows of dorsal kineties, one left and two right rows of marginal cirri, and an “Oxytricha-like” pattern of ventral cirri. The parts of the macronucleus are variable in shape and number. The comparison with other members of the genus shows that P. indica differs from other congeneric species in the combination of these characters.  相似文献   

19.
Pseudorthocladius cristagus sp. n. is described as male imago. It differs from all other members of the genus Pseudorthocladius v. d. Wulp except P. pilosipennis Brundin by having setae on the wing membrane. It can be separated from P. pilosipennis by having a gonostylus with a prominent crista dorsalis and an outer corner or heel. The species was collected with emergence traps from a helocrene spring in northern Luxemburg.  相似文献   

20.
Two new species of the genus Aturus Kramer (A. tuzovskyi sp. n. and A. kimichungi sp. n.) from Russia are described. These species and closely related species of the genus Aturus are compared. A. tuzovskyi sp. n. male is characterized by a slender body, the presence of a pair of bifurcated setae on the dorsal shield, two sword ventrodistal setae equal in length on the genu of leg IV, and 10–14 pairs of acetabula. The female of this species is characterized by the oval body and the presence of 10–13 pairs of acetabula. The male of A. kimichungi sp. n. is characterized by a rounded body, the presence of a single pair of bifurcated setae on the dorsal shield; sword setae on the genu IV are longer than tibia IV; 14–21 pairs of acetabula are present. The female of this species possesses a rounded body and 18–19 pairs of acetabula.  相似文献   

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